Earth news

The Sudden Freeze 8,000 Years Ago

From Planet Oregon.com
Elaine Meinel Supkis

8,000 years ago, camels and giant sloths ran around in Arizona which wasn't so arid back then. They all went extinct very suddenly when something odd happened back then. The whole world underwent some pretty sudden and violent see-saws back then and this has bearing on today since the forces at work were varied but human were the keystone, we are the domesticators and the destructors for this is the same period we figured out how to domesticate many plants and animals.

From Associated Press:

Workers digging at the future site of a Wal-Mart store in suburban Mesa have unearthed the bones of a prehistoric camel that's estimated to be about 10,000 years old.

Arizona State University geology museum curator Brad Archer hurried out to the site Friday when he got the news that the owner of a nursery was carefully excavating bones found at the bottom of a hole being dug for a new ornamental citrus tree.

"There's no question that this is a camel; these creatures walked the land here until about 8,000 years ago, when the same event that wiped out a great deal of mammal life took place," Archer told The Arizona Republic.

So many forces were at work in that critical phase, 8,000 years ago. Evolution doesn't happen unless ecological niches suddenly change or are invaded. So when we see sudden extinctions, this means the enviroment changed and niches could no longer be inhabited. And usually, this also means other life forms evolve rapidly as they invade previously-occupied niches.

So let's look at the climate 8.000 years ago: according to many studies, the last Ice Age ended suddenly around 11-10,000 years ago. The massive glaciers melted rapidly. Now, in previous ice-melts, the large Ice Age fauna would simply move north but 8,000 years ago, most of them went extinct. With incredible speed.

This figure shows snow accumulation and isotopically inferred temperature records in the Greenland GISP2 ice core and a temperature record derived from oxygen isotope measurements of fossil shells in the sediments of Lake Ammersee, southern Germany. These records all show a major climatic instability event which occurred around 8200 years ago, during the Holocene. The event was large both in magnitude, as reflected by a temperature signal in Greenland of order 5 �C, and in its geographical extent, as indicated by the close correlation of the signal in these two locations. The dramatic event is also seen in the methane record from Greenland (not shown here) indicating possible major shifts in hydrology and land cover in lower latitudes. source: Von Grafenstein et al (1998) Climate Dynamics, 14, 73-81.

Not only was there a brief, sharp drop in temperatures but there was also a decrease in snowfall in Greenland. The sharpness of this event, the suddeness is curious. People propose all sorts of things like the ocean suddenly changing its course as the Gulf Stream moves southwards, for example. But even if that were so, it wouldn't be so brief as well as sudden. And if the Gulf Stream changed course frequently, this would be periodic, it would occilate.

But this is sudden, brutal and brief. And it coincides with many singular and amazing events and changes in the way the ecosystem worked. So I decided to line up some of these events that could have triggered such a change.

We know that the earth has an eccentric orbit and tilt which probably is an artifact of when something really, really big slammed into the earth and created the moon 3 billion years ago. Because of this, the amount of sun shining on parts of the earth varies greatly over a 23,000 year cycle.

From Lake Powell.net:

The third cycle is due to precession of the spin axis (as in a spinning top) and occurs over a ~23,000 year cycle. Presently, the Earth is closest to the Sun in January and farther away in July. Due to precession, the reverse will be true in ~11,000 years. This will give the Northern Hemisphere more severe winters.

When all the Milankovitch cycles (alone) are taken into account, the present trend should be towards a cooler climate in the Northern Hemisphere, with extensive glaciation. The Milankovitch cycles may help explain the advance and retreat of ice over periods of 10,000 to 100,000 years. They do not explain what caused the Ice Age in the first place.

Other factors which work in conjunction with the Earth's orbital changes include:

The amount of dust in the atmosphere
The reflectivity of the ice sheets
The concentration of greenhouse gases
The changing characteristics of clouds
The rebounding of land, having been depressed by ice.

I have lived through several significant but of course, none were huge, volcanic events and each time, the sun rises and sun sets are spectacular and it changes the climate drastically. When Mt. Pitumbo in the Philippines blew out a large amount of dust, it made things significantly colder insantly. I was living in a tent on my mountain. The previous year was very warm and that winter, hardly any snow.

Then the volcano blew. I could see the fine white dust in the high statosphere. Immediately, it was cold. It was early June and we wore coats and the wind blew hard. World temperatures dropped over 3 degrees F. Then we had amazing amount of snow that winter and the following summer was cold because of red dust from Mongolia which gave sunny days a brass sheen to the sky.

It wasn't a great volcanic event but the Mt. Toba eruption in 1812 made it so cold in Berlin, NY, there was snow all summer in the mountains and people nearly starved to death.

National Park Serive, US Gov.

Right now there is furious debate about the impact of human activities on global warming. It is the sun, the tilt of the earth, changes in agriculture? What is warming up the planet? The interaction between climate and humans balancing or unbalancing each other goes way back to when there were not so many humans on earth, a key climate change was when the last Ice Age suddenly ended and then suddenly became extremely cold 8,000 years ago and then has basically warmed up as humans terraformed this planet increasingly. What is going on here?

From Science Daily:

Methane gas released by peat bogs in the northern-most third of the globe probably helped fuel the last major round of global warming, which drew the ice age to a close between 11,000 and 12,000 years ago, UCLA and Russian Academy of Sciences scientists have concluded.

Methane released by the massive northern peatlands complex in western Siberia contributed to global warming at the end of the Ice Age. (Credit: Karen Frey)

But the new information in no way lets human sources of greenhouse gases off the hook for the present round of global warming, warn the team of researchers whose findings appear in the Oct. 13 issue of Science.

Just because something happens and then something else happens doesn't mean these things were the exclusive or even the most important causes of other events. All things influence each other and releasing gas from bogs can add chemicals to the atmosphere which has an effect but the cyclic nature of the Ice Ages and how they began in recent times, geologically speaking, means the cycles can't be simply organic.

We already suspect major literally earth-shaking events leads to evolutionary death spirals and evolutionary swings, things like asteroids and meteorites have periodically wiped out many of the existing life forms in the past. So 8,000 years ago, something was afoot.

From NYAS.org:

Past orderly climate cycles support this new hypothesis: during past periods that followed glaciations, temperatures rose, peaked, and then fell to a threshold that triggered the next glaciation. During these interglaciations, atmospheric levels of two greenhouse gases (GHGs), methane and CO2, rose, then fell.

But following the last glaciation, temperatures rose as expected, then started to fall but did not continue to fall. Levels of CO2 and methane rose and continued to rise when they should have fallen.

This deviation from natural trends was caused by humans. Notably, agriculture employing irrigation, particularly wet-rice farming, started boosting methane levels around 5000 years ago. Deforestation and biomass burning started boosting CO2 levels around 8000 year ago. Higher levels of these GHGs kept the Earth warm and prevented temperatures from falling to a threshold that would have triggered glaciation.

8,000 years ago, slash and burn societies lit many fires. Today, many forests are being burned in all the jungle sectors and this not only reduces plant cover but it also releases gasses trapped in the leaf litter in swampy areas which, exposed to the sun, dry out and this causes fires to spread even wider when humans burn the upper story off.

Also, hunters of big game discovered they could drive game off cliffs and trap them along rivers if they lit long fires and hunted in large groups. This is probably why few of the large Ice Age mammals survived this latest interglacial. Fires reduce sunlight and can cool off things and if humans did too much burning, it could have changed rain patterns and reduced the warmth. But I doubt this would cool the entire planet nearly insantly as the charts above clearly show.

From Bellarmine.edu:

At the same time as early Americans may have been planting their first squash, hunter-gatherers some 16,000 kilometers east along the banks of the Yangtze River were beginning to cultivate wild rice, according to new studies by archaeobotanist Zhijun Zhao of the Smithsonian Tropical Research Institution and colleagues. Rice, the most important food crop in the world, was long thought to have been cultivated first around 6500 years ago in southern Asia, where the climate is warm enough to support luxuriant stands of wild rice. But in the 1980s, ancient bits of charred rice turned up in a site along the banks of the middle Yangtze River, in the far northern edge of the range of wild rice today. Directly carbon-dated to 8000 years ago, these grains are the oldest known cultivated rice and suggest that the center of rice cultivation was actually farther north.

8,000 years ago, we left the Garden of Eden and became cultivators and herders. This is when we corralled the sheep and began to feed and pet the cats (talk about trans-species conquests!)---um, cats, I should say, decided to colonize humans---heh---it must have been raining a lot and the mice were trying to get into the newly-harvested grains and the cats let the humans know they love warm, dry places and petting. The dogs hung out with the herders and helped move the sheep around and fight off the wolves, tigers, lions and jackals.

From Wikipedia:

Rise of agriculture.

First known marriages in Ancient Near East.
Potatoes and beans are cultivated in South America
Beginning of rice cultivation in East Asia
Domestication of the cat and Bos aegyptiacus ox in Ancient Egypt
Domestication of sheep in Southwest Asia
Huts, hearths, granaries, and nonportable stone tools for grinding grains Africa
Catal Huyuk, men wear animals skins, plus hats of the same material Asia
Houses, kilns, pottery, turquoise carvings, tools made from stone and bone—and most remarkably—bone flutes China
City located in Anatolia, or modern day Turkey where a number of artifacts appear to support evidence for the widespread practice of Goddess worship

All across the planet, many humans living in places that suddenly changed in this brief jerk of temperature change, all began desperately to farm instead of simply walking about, plucking out of nature, things to eat and since farming and protecting harvests, crops and homes is very hard labor, one should assume this was taken up only out of desperation. When things stabilized again 7,000 years ago, I bet many people reverted to the old ways but enough stuck to the agriculture, it grew for the stability of farming means families are stronger as families instead of wandering in the wilderness, they created 'civilization'. And this is the time the Sahara began to dry out and the gentle savanahs turned to howling wastelands except for the great rivers like the Nile and the Euphrates.

But I very seriously doubt humans had a gigantic impact on the world's TEMPERATURES and rainfall! So this bad session of weather 8,000 years ago had another source: Volcanoes.

From Fox News:

A volcano avalanche in Sicily 8,000 years ago triggered a devastating tsunami taller than a 10-story building that spread across the entire Mediterranean Sea, slamming into the shores of three continents in only a few hours.

A new computer simulation of the ancient event reveals for the first time the enormity of the catastrophe and its far-reaching effects.

The Mt. Etna avalanche sent 6 cubic miles of rock and sediment tumbling into the water — enough material to cover the entire island of Manhattan in a layer of debris thicker than the Empire State Building is tall.

The mountain of rubble crashed into the water at more than 200 mph. It pummeled the sea bed, transformed thick layers of soft marine sediment into jelly and triggered an underwater mudslide that flowed for hundreds of miles.

There was a major eruption on Versuvius 8,000 years ago. The tsunami certainly had an impact for many humans lived along the shores of the Mediterranean Sea and I fear many were swept aways in this terrible event. Whole islands were cleared along the shores of Greece and the lowlands at the terminus of the Nile as well as the shores of the Middle East were hammered hard.

But this wouldn't change the global climate although the active volcano did add gasses and dust to the stratosphere. This wasn't an ordinary eruption, either, it was pretty powerful. But it wasn't the only volcano to erupt.

USGS.gov:

Toya Caldera lies in the V-shaped intersection of the Kurile and Japan arcs, along both of which the Pacific plate is subducted northwesterly direction beneath the Eurasian plate at a rate of approximately 10 centimeters per year (Circum-Pacific Map Project, Northwest Quadrant Panel, 1981).

Toya Caldera formed by collapse about 110,000 years B.P., based on the age of pyroclastic deposits that have been related to the caldera-forming event (Ikumura and Sangawa, 1984; Machida and others, 1985; Ikeda and Katsui, 1986). Usu is a truncated stratovolcano with late-stage dacitic domes, located on the southern boundary of Toya Caldera. The main body of Usu was formed by eruptions of basaltic and andesitic magma (Usu somma lava). Then, 7,000 to 8,000 years ago, a violent explosion and a large debris avalanche formed a somma that is now largely filled by dacitic domes. Viscous dacitic magma has on occasion upheaved the land surface by more the 200 meters directly above a cryptodome (for example, Showa-shinzan ("Roof Mountain") in 1943-45).

Most of Toya Caldera is occupied by Lake Toya; the Naka-jima (or Nakano-shima) group of andesitic domes formed an island in the center of Lake Toya before Usu Volcano began to grow. Two additional domes have been identified by bathymetric and magnetic studies of the caldera lake (Nishida, 1984). On the basis of the same magnetic survey, Nishida (1984) proposes that the diameter of the Toya Caldera structure is only half that of the present topographic depression; if so, Usu lies outside the main structure of the caldera, on its modern topographic rim.

Some geological periods see few major volcanic events while others are for some reason, very active. 8.000 years ago was very active. Any event that produces a caldera is a major event. The bigger and deeper the caldera, the more it affects the climate. We know that an eruption 76,000 years ago nearly wiped out humans and the survivors are our ancestors. They had to work hard to survive in very difficult circumstances. On top of this, super-eruptions can cause Ice Ages which are very difficult to survive if one comes from creatures that once lived in jungles, not on ice sheets.

So I kept looking for volcanic events that would force humans to give up their happy-go-lucky ways and end up creating argriculture and herding animals.

From Travel Kamchatka.com:

Gorely Volcano: A massive shield volcano 1830 m high. Massive andesite lava accumulation in the Early Pleistocene was followed about 33,000 years ago by production of about 120 km3 of ignimbrite accompanied by caldera collapse. Basalts and basaltic andesites then created five volcanoes that coalesced to form most of the modem mountain between 8000 and 6000 years ago; this largely filled the caldera, but sections of the old caldera walls remain visible just outside the shield. Subsequent activity has been on a reduced scale, producing both lavas and tephras; these are exposed in the walls of the summit complex of craters. Recent eruptions have been explosive; in 1981 ash covered an area of 500 km2, and the last eruption was in 1986 when a cloud of steam and ash rose 600 m.

8,000 years ago, the bridge to the New World was broken by the oceans which were rapidly rising and volcanoes along that chain were erupting with violence. The sea water rushing out of the Arctic probably changed the salinity and temperature of the north Pacific. Maybe this triggered volcanic actions because water does interact with volcanic sources to cause steam and then eruptions. Perhaps this unrush of water caused the current flowing around Greenland to change significantly? This could explain why this interglacial is longer than others.

But it doesn't explain the short but brutal cold/dry spell that caused humans in the New World and the Old to both independently develop agriculture at the same time.

From Wikipedia, Mount Shasta:

Since then the Shastina cone has been built by mostly pyroxene andesite lava flows. Some 9,500 years ago, these flows reached about 6.8 miles (11 km) south and three miles north of the area now occupied by nearby Black Butte (see image at right). The last eruptions formed Shastina's present summit about a hundred years later. But before that, Shastina, along with the then forming Black Butte dacite plug dome complex to the west, created numerous pyroclastic flows that covered 43 mile² (110 km²), including large parts of what is now Mt. Shasta, California and Weed, California. Diller Canyon (400 ft (120 m) deep and quarter-mile (400 m) wide) is an avalanche chute that was probably carved into Shastina's western face by these flows.

The last to form, and the highest cone, the Hotlum Cone, formed about 8,000 years ago. It is named after the Hotlum glacier on its northern face; its longest lava flow, the 500 ft (150 m) thick Military Pass flow, extends 5.5 miles (9 km) down its northwest face. Since the creation of the Hotlum Cone, a dacite dome intruded the cone and now forms the summit. The rock at the 600 ft (180 m) wide summit crater has been extensively hydrothermally altered by sulfurous hot springs and fumaroles there (only a few examples still remain).

This was pretty significant. The American West was rapidly rebounding as the glaciers not only melted but waves of floods poured across the land and rifts opened up and large volumes of lava poured out and obvioiusly, as the North American continent moved relentlessly westwards, the ice sheets could have impeded movement and so this freeing up of stored energy must have led to some pretty amazing earthquakes and we can see, there was a lot of volcanic activity.

But this is in general. There had to be a great event which involved the blowing up a major volcano, an epic event and so there was.

From NPS.gov:

Mount Mazama’s most violent eruption occurred about 7,700 years ago. A column of hot gas and volcanic rock was ejected high into the air. This ejected magma fell to the earth as fragments of frothy white pumice and volcanic ash. Layers of ash from this eruption may still be found in the soil as far away as Alberta, Canada.

Explosions on the northeast side of Mount Mazama produced fast-moving flows of hot ash. In all, 12 cubic miles (50 cubic kilometers) of material poured out of the erupting volcano, draining the magma chamber beneath the mountain. As the underlying support for the mountain was lost, the walls of the volcano began to collapse inward. The top of a mountain that was built over hundreds of thousands of years “disappeared” in perhaps just a few days.

Here is my own candidate. This eruption was huge. It was also on the edge of the retreating Ice Sheets. There was lots of water around. The mountain didn't 'disappear' when it collaped and then blew apart: it went flying into the stratosphere. And the earth was covered by a really thick blanket of fine dust! Temperatures fell dramatically.

And humans had to scratch the earth and protect the plants if they wanted to eat.

This volcano, like the Yellowstone caldera, is still active. There are many candidates for similar blow-ups. These mega-events are around 10,000 years apart which is not reassuring. But then, this is why our planet has evolution and is so full of life: it is, itself, alive. Not frozen in time like the moon, for example.

And so it goes: the dynamic sun that constantly reinvents itself and is relentlessly changing as it ages, the things flying through space that hit us periodically, the oceans, volcanoes, continents moving restlessly, wind patterns, the tilt of the earth, the moon's pulling on everything here and life forms adding and subtracting from it all, a marvelous and hazardous place, this is the earth.

Culture of Life News Main Page

The Ecocene Hyper-Warming: Causes and Effects

Elaine Meinel Supkis

Once again, scientists would like to find just one cause of some great geological/evolutionary/climate event, this time the incredible Ecocene warming that came 10 million years after the end of the dinosaurs. The truth of the matter is, many things contribute to these epic periods: the sun's energy, interstellar objects, volcanic activity caused by plate tectonics and of course plants and animals interacting with each other and the oceans, changing the chemistry of the atmosphere and the waters of this planet.

From Britbart.com:

An extraordinary burst of global warming that occurred around 55 million years ago dramatically reversed Earth's pattern of ocean currents, a finding that strengthens modern-day concern about climate change, a study says.

The big event, the Palaeocene/Eocene Thermal Maximum (PETM), saw the planet's surface temperature rise by between five and eight degrees C (nine and 16.2 F) in a very short time, unleashing climate shifts that endured tens of thousands of years.

The warm event lasted from the age of the dinosaurs until 40 million years ago when it began its long, long decline. A host of huge changes in our flora, fauna and the sun occured this last 60 million years. The chief thing that changed was the colonization of the lands as well as the seas by totally different creatures and plants.

From Math.UCR.Edu:

The flowering plants and grasses took over the lands. Feathered and furred animals took over much of the land's niches. And the sun grew much older and moved into new parts of the great Milky Way galaxy that had sucked in the small mini-galaxy that was the womb of this insignificant, old, yellow star. As the star burns its fuel of hydrogen and increases its helium content, the core of the star becomes increasingly destabilized. But we dare not think about that, right?

We can control our pollution but we cannot control the sun at all, not even slightly.

From the article:

With a painstaking reconstruction, Nunes and Norris found that the world's ocean current system did a U-turn during the PETM -- and then, ultimately, reversed itself.

Before the PETM, deep water upwelled in the southern hemisphere; over about 40,000 years, the source of this upwelling shifted to the northern hemisphere; it took another 100,000 years before recovering completely.

What unleashed the PETM is unclear. Most fingers of blame point to volcanic eruptions that disgorged gigatonnes of carbon dioxide, or coastal reservoirs of methane gas, sealed by icy soil, that were breached by warmer temperatures or receding seas.

Let's travel back in time: it is right after asteroids slammed into the earth when the sun passed through some of the dust trails that this galaxy is sucking in, that black stuff that hided the brilliant heart of this galaxy, its gigantic black hole, from us. When some of these asteroids slammed into the earth's oceans, it caused tremendous floods, tsunamis and rain, lots and lots of rain.

The many tiny furred or feathered creatures clinging to the frondy trees and forest understories survived this degradation of the climate. Oh, how they huddled as the hours between stormy onslaughts would pause enough to let some of the sun in and then the rain would pound down again! There is tremendous erosion as plants are swept away.

This map from Ohio University shows where the angiosperms, the flowering trees and plants, radiated out from: the greatest rift valley in the history of geology: the point where Africa and South America seperated.

This is where the Congo and the Amazon rivers, two of the earth's greatest drainage basins co-joined and flowed into the growing Atlantic Ocean. The fact that all trees and flowers that survived the destructive rains grew in this zone is very interesting. For this is where the lemur-like ancestors of ourselves lived. And it is where many mammalian creatures survived the destruction of their environment. None were larger than a large cat or small dog. This tells us how terrible things were for all the large land therapsids died.

Back to the storms post-asteroid hit: the Atlantic Ocean which had already begun to enlarge between North America and Africa (Europe still being attached at the top of the globe), the salinity level must have not been very great and these rains fed even more purified water. For when the asteroid slammed into the ocean, a lot of salt water ended up on land and this killed most of the dominant plant species.

From New Scientist:

The volcanic eruptions that created Iceland might also have triggered one of the most catastrophic episodes of global warming ever seen on Earth, a new study suggests.

Michael Storey at Roskilde University in Denmark and colleagues have found evidence that a huge volcanic eruption, 55 million years ago, unleashed so much greenhouse gas into the atmosphere that world temperatures rose by as much as 8°C – with the Arctic ocean reaching a toasty 25°C.

"It was already a warm Earth, and it got a lot warmer," says Storey. The climatic turmoil that ensued was disastrous for most life, he says, killing off many deep-sea species.

Ancient ocean sediments that record this episode, called the Palaeocene-Eocene Temperature Maximum (PETM), also contain an unusually small amount of the heavier isotope of carbon, carbon-13. The sediments point to a sudden influx of available carbon dioxide or methane – which would explain the sudden warming – from some source with reduced carbon-13 levels.

OK: when the Atlantic came pouring into what was hither-to, a rift valley with swamps filled with dinosaurian creatures and giant crocodiles, etc, suddenly became ocean. And the space between the continents was spreading which meant, there was a lot of underwater volcanic action going on, I would suggest this break-up of the continents was like opening the door to hell: it being the core of the planet. This released energy into the upper systems of this planet, heating them up from below. Namely, the Atlantic, which was much shallower than the Pacific, was easily warmed this way. The fissure in the earth's crust runs the entire length of the planet, after all!

And we know that huge amounts of very hot lava poured out of this fissure. Warm oceans breed big storms. So the climate wasn't like the earlier one with a lot of moisture but not huge storms with high winds, I bet. After all, a major problem being a gigantic dinosaur would be lightning. Indeed! Despite all the movies showing Tyrannosaurs running wild in lightning storms, this is impossible. They would be struck by lightning bolts and killed pretty fast!

I know this for a fact. In bad lightning storms, I would rush out into the pastures to gather up Chip and Dale, my huge ox team. No way would I leave them out there with their big horns and broad backs with lightning seeking targets! I never worried about the sheep who were small and low to the ground.

So, this new climate had lightning bolts a-plenty. And the small mammals probably shivered and shrieked as lightning storms bore down on them! And the gases released by the huge fissure that opened up right in the center of where the survivors of the asteroid hid probably changed the ocean's chemistry since the Atlantic was more like the Mediterranean at this time. I suppose, when the temperatures rose, the salinity of this new ocean was intensified as evaporation competed with the incoming rain waters.

And the slender, new ocean between Africa and South America must have gotten very saline as the northern waters flowed in this hot channel that had lots and lots of lava activity. Probably the switch in direction of these waters was due to changes in salinity and temperature as the ocean grew wider and wider.

From Lost Kingdoms:

The Eocene Epoch (55-38 million years ago)
By the beginning of the Eocene, Gondwana had almost split apart, but Australia, Antarctica and South America remained joined. The Antarctic portion of Gondwana straddled the South Pole but because the global climate was warmer it was free of ice and snow. A forested corridor linked Australia and South America.

Because Antarctica was ice-free, this means the oceans had to be much warmer than today. Did the hot waters from the Atlantic kitchen heat up the Pacific? There was yet another tectonic plate event over there: India shot nortwards at an amazing speed and slammed into Asia. It passed over a hot spot in the ocean that caused a huge lava event, the Deccan Traps. This changed the atmosphere's chemistry in a big way as well as this hot spot probably heated up the ocean between Antarctica and India.

From Mongabay:

Based on new findings on the PETM, increasing amounts of greenhouse gasses in the atmosphere will also have dramatic impacts on land ecosystems. Research released last week in Science reports that a rapidly warming climate 55 million years ago caused significant changes in forest composition and distribution.

“It indicates that should we have a period of rapid global warming on that scale today, we might expect very dramatic changes to the biota of the planet, not just the mammals and other vertebrates, but forests also completely changing,” said Jonathan Bloch, a University of Florida vertebrate paleontologist and member of the research team for the Science paper.

After an initial period of increasing aridity in northern latitudes like the study site of Bighorn Basin in northwestern Wyoming, it appears that plants species migrated towards higher latitudes and forests transitioned towards warm tropical ecosystems with closely spaced trees, ideal for the evolution of primates. Further, global warming allowed mammals -- including rhinos and the earliest known horse -- to emigrate across northern land bridges to expand into new habitats.

55 million years ago, mammals were finally radiating out of their rift valley. They started out small, clinging to trees for the most part. The previous era featured gigantic animals that ate much of the plants that grew then. But now the flowering plants took over rapidly and eventually covered all the lands and few cropped them down. Next came the insects and following them, the bedraggled tree dwelling ancestors of ours, insect eaters exploiting this new, abundant niche.

On land, many new types of mammals appear in a dramatic evolutionary radiation, filling the ecological roles vacated by the dinosaurs. But compared to the majestic Cretaceous megafauna, these animals were puny. No Paleocene mammal exceeded the size of a small modern bear, and most were a lot smaller. They were all short-legged and plantigrade (walking on the soles of their feet), and they had five toes on each foot, a primitive feature. Most or all have fourty-four low crowned teeth, another primitive feature. Almost all of them had slim heads with narrow muzzles and small brain cavities. In terms of brain to body weight ratios they were well below late Cenozoic mammals. A number of typical Paleocene mammals are shown in the following sketch by Dr Bob Bakker.

From Palaeos.com:

When plants dominate the environment, they release a lot of oxygen and change the chemistry of the soil, the air and water. So the gases they released during the 2-3 million years of few eaters of plants after the extinctions, the atmosphere would heat up and not go down again even as the insect and animal population takes off and starts making a dent in the abundant plant life.

From the article above:

A 400-metre-long core of sediment recovered near the North Pole shows the region was subtropical about 55 million years ago.

Scientists consider the Arctic to be a bellwether for climate change, but until recently, they've had to rely on samples collected thousands of kilometres away from the Pole.
*snip*
First, the Arctic Ocean went through a warm period with temperatures of 23 C, like a tepid bath. Then, about 49 million years ago, freshwater was released into the Arctic, cooling it to about 10 C.

At the time, the salinity was dilute enough for freshwater ferns to cover much of the surface in the summer, the team said.

The fast-growing greenery likely absorbed carbon dioxide, helping to cool the Arctic, theorized Henk Brinkhuis of Utrecht University, a co-author of one of the papers. Pebbles carried to the middle of the Arctic basin, dropped by icebergs, suggest ice started to form about 45 million years ago, the start of the region's current "icehouse" conditions.

Now that, I find most interesting. The fresh water sat on top of the salty water and cooled it down but not enough for ice, enough for ferns like we see in the lakes here in the Northeast. Namely, winter doesn't bother them, the snow and ice melts and the ferns grow like crazy.

Still, looking at the chart at the top here, one can see that the global cooling was gradual until 35 million years ago when it suddenly plunged, becoming significantly cooler. And this was the dawn of the Grazing Era--hoofed eaters of grasses evolved rapidly in size and numbers, growing to massive size in some cases, radiating outwards as they took over the ecosystems of all the continents except for Australia.

The Paleocene carnivorous mammals of Laurasia had to share their world with giant flightless birds of prey like Diatryma and it's cousins (order Diatrymiformes), which appear suddenly during the late Paleocene and continue through to the Middle Eocene. Standing 2 meters or more in height and weighing in at around 200 kg, these large-beaked birds were the biggest and fiercest animals on land for some five or ten million years. In South America similar giant predatory birds, the Phorusrhacids, are known from the Eocene but most probably likewise evolved during the Paleocene. These great birds were the last successors of the mighty theropod dinosaurs of the Mesozoic.

Due to their mobility, birds spread into every niche faster than mammals. It is amusing that a giant bird evolved so swiftly. Vultures, turkeys and penguins can be quite large today but not the gigantic size from this age where almost all the mammals were still quite small.

From CWRU.edu:

There is one thing we have to consider when picking and choosing causes of climate change and that is, not all living things go through the same extinction cycles at the same time, indeed, plants run on a different schedule, it seems.

From Ohio Edu:

d) Only 2 tracheophyte extinctions coincide with a "minor" vertebrate mass extinction, none coincide with marine invertebrates-->environmental and other catastrophes have drastically variable effects on different organism groups

And this means anyone who suggests that this thing or that process caused vast climate changes could be mistaken. Namely, it is a confluence of forces building up over time. Oceans forming or closing off, cracks or hot spots causing massive lava events, volcanic gasses or volcanic dust, solar activity or inactivity, the solar system passing through dirty parts of the galaxy versus relatively clean sectors, and the density and type of life forms: all these together, move the environment and the weather.

From BBC:

This lost landscape, where hunter-gatherer communities once lived, was swallowed by rising water levels at the end of the last ice age.

University of Birmingham researchers are heralding "stunning" findings as they map the "best-preserved prehistoric landscape in Europe".

This large plain disappeared below the water more than 8,000 years ago.

The Birmingham researchers have been using oil exploration technology to build a map of the once-inhabited area that now lies below the North Sea - stretching from the east coast of Britain up to the Shetland Islands and across to Scandinavia.

The world's shorelines have changed frequently as the oceans rise or fall depending on where ocens are forming or being closed off as well as thickness of ice sheets or if ice sheets can even form. The continental shelves probably hold a treasure trove of fossils which can't be dug up yet due to difficulties. Mostly, core samples are drilled. But this is really a hit or miss thing and I would expect we would find many wonderous fossils there if we could.

Maybe if there is another Ice Age, perhaps.

Culture of Life News Main Page

Los Nevados del Huila Erupts In Columbia

Elaine Meinel Supkis

A volcano in Columbia caused a landslide/eruption/flood. This valley has been the site of previous disasters as it is one long chain of volcanos and mountains, the northern sector of the Andes. One feature of volcanos is how 'sleeping' volcanoes can suddenly not only erupt but completely explode with very little warning.

From Associated Press:

Thousands of people were evacuated after a long-dormant volcano erupted late Tuesday and again early Wednesday, provoking avalanches and floods that swept away houses and bridges.

The Nevado del Huila volcano's eruptions were its first on record since Colombia was colonized by the Spanish 500 years ago.

There are about 10,000 people living in the area around the volcano, and about 3,500 had been evacuated, Luz Amanda Pulido, director of the national disaster office, told The Associated Press after flying over the volcano in southwest Colombia.

These volcanos are 'dormant' until they are not 'dormant'. Namely, this classification is spurious. Some calderas and volcanos might be inactive such as some of the ones around Tucson, Arizona, for example. But generally, it is a guessing game, not a science. It seems volcanic rifts are possibly one time events, the ones that leave behind various forms of 'sawtooth' mountains.

This particular volcano is actually rather active on the geological scale. About 20 years ago, we saw a major volcanic eruption in Mexico which clearly shows there is no such thing as a truly 'dormant' volcano: From Vulkaner:

El Chichon is the most southern and eastern volcano in Mexico.

It is a small, but powerful andesitic tuff cone and lava dome complex that occupies an isolated part of the Chiapas region far from other Holocene volcanoes. Prior to 1982, this relatively unknown volcano was heavily forested and of no greater height than adjacent non-volcanic peaks. The largest dome, the former summit of the volcano, was constructed within a 1.6 x 2 kilometer summit crater, created about 200,000 years ago.

Two other large craters are located on the SW and SE flanks. More than a half dozen large explosive eruptions have occurred since the mid-Holocene. The powerful 1982 explosive eruptions of high-sulfur, anhydrite-bearing magma were accompanied by devastating pyroclastic flows and surges and destroyed the summit lava dome. The eruptions created a new 1-kilometer-wide crater that now contains an acidic crater lake.

El Chichon might have erupted from about 270 CE and every 500 to 600 year since, in about 700, 1350 and 1850, with explosive eruptions followed by pyroclastic flows. Then suddenly in 1982 it woke up again, way out of schedule. Prior to 1982, it was thought to be extinct. Consequently, activity of the volcano was not being monitored and the 1982 eruption was a total surprise (although, with hindsight, local inhabitants had noticed increased earthquake activity for some months prior to the first eruption).

This eruption buried a city as well as much of the farmlands surrounding it. The ash was so thick, it was night for 44 hours in a nearby city. The volcanic tuff was so thick, it was more than 30' in places. The entire top half of the volcano blew up and turned a dome covered with forest into a steaming hot caldera.

There were a few small forewarnings it was going to blow up. The streams and rivers running down from this volcano smelled of sulfur and became much hotter. Micro quakes rattled the people living on the flanks of the volcano but since it was 'dead', no one took all that seriously. It erupted the first time with no warning. This was the small, 'normal' eruption with a big plume and so on. But before anyone could really be evacuated, as the volcanists flown into the region could barely set up their equipment, the top half of the mountain exploded and anyone within 30 miles of it was buried under many feet of tuff and rocks.

Why do they suddenly blow up like this? The Andes has armies of such mountains. Mexico has quite a few and there are several important ones in the North American west as well as Alaska, of course. We know that Yellowstone is this hot spot that creates one giant caldera after another, each time, very explosively. The nastiest volcanic events in all of North America come from this one entity. But El Chichon was a fairly quiet mountain and no one had seen it erupt or even hiss a tad since the European invasion of Mexico. There are similar potential volcanos all over the place. We can't tell if they are active until they decide to be active.

Here is a photo from the National Geographic that came out back when no big volcanos had erupted in quite a while.

From my parent's book, 'Sunsets, Twilights, and Evening Skies':

There had been so little volcanic action since 1900, volcanists were quite annoyed. Off in Indonesia, Agung suddenly had a very powerful eruption. Suharto was badly shaken, politically, since it was considered his fault the Volcano Gods didn't like him. Communications and observation of the earth were so scant back then, we knew about this eruption long before it made the news because it lit up the sky so amazingly.

I learned years ago to put my hand over the sun to see if there is any 'haze' that is different from normal cloud cover. One can even see the fine, red dust from Mongolia after a bad drought and windstorm this way, the sky has this even copper sheen. With white dust from volcanos, this is different from high cirrus clouds because it is even from horizon to horizon. Since 1963, a host of volcanos have put into the stratosphere all sorts of combinations of dust and or aerosols and each combination creates different light effects at sunrise and sunset as well as affecting the weather tremendously.

Indeed, I would suggest the earth is undergoing a major spasm right now. The frequency of major earthquakes coupled with volcanic actions suggests the earth goes through phases and this is an active phase. Certainly, the sudden releasing of pressure on several continents due to swift ice melting might be affecting the entire planet.

From the USGS:

By removing a large part of a volcano's cone, a landslide may abruptly decrease pressure on the shallow magmatic and hydrothermal systems, which can generate explosions ranging from a small steam explosion to large steam- and magma-driven directed blasts. A large landslide often buries valleys with tens to hundreds of meters of rock debris, forming a chaotic landscape marked by dozens of small hills and closed depressions. If the deposit is thick enough, it may dam tributary streams to form lakes in the subsequent days to months; the lakes may eventually drain catastrophically and generate lahars and floods downstream.

The valleys around today's volcanic event have seen many landslides in the past. It is a very dangerous region for humans. Landslides are like tsunamis in many ways. Instead of happening in the ocean and sweeping towards land, it is land sweeping into lakes and rivers and causing them to surge as well as simply covering everything in tons of dirt and rock.

Today's event is similar to the one back on June 6, 1994: From USGS:

Within minutes of a magnitude 6.4 earthquake beneath the SSW flank of Nevado del Huila volcano, dozens of landslides swept from the steep valleys above Río Paez into the river. The landslides quickly turned into debris flows, which joined to produce a single enormous flow of water, rocks, soil, and trees in Río Paez. The lahar destroyed most or parts of several towns along the river, including Dublin, Irlanda, Toez, and Belalcazar, killed several hundred people, and displaced about 20,000 people from their homes. Six bridges and >100 km of roads were destroyed.

Map from the USGS.

The huge flow wave originated from both hydrothermally altered rocks of Huila Volcano and the ash-mantled terrain surrounding the volcano. Whether triggered by a large earthquake, intense rainfall (for example, see Casita Volcano), or both, this tragic event illustrates that both volcanic cones and steep hillslopes around them can collapse to form landslides and debris flows.

This region is full of wild life. They survived so long because the region is dangerous for humans. Even as humans invade increasingly dangerous zones, the wild animals retreat into the mountains. One of these is the endangered species called 'the Mountain Tapir'. From Tapirs.com:

Mountain tapirs occupy the mountainous terrain of Colombia, Ecuador and Peru. They weigh up to 225 kg and can be up to 1.8 meters long. They are an endangered species, and the rarest of the tapir species.
*snip*
A unique feature that tapir posess is its fleshy prehensile nose that it uses to grab leaves and even use as a snorkle while swimming. Their hides are very tough but streamlined for easy maneuvering in the forest. Tapirs are "seed dispersers." They eat seeds that are then dispersed in their scat which helps the forest to regenerate.

Tapirs are herbivores best suited to primary or old growth secondary forest, and their reproduction is slower than most mammal species due to a long gestation period (13 months) and to the fact that there is only one offspring per gestation.

As these curious little animals with many hooves on their feet, distant relatives of the rhino. They are now scattered along patches of volcanic lands mostly in Columbia. Just like the Chiapas and the Agung events, poltical fortunes and rebellions accompany volcanic eruptions. And these rare animals struggle to live in this difficult situation.

This is true of all caldera or volcanic regions. For example, the USA has confined most of the remaining members of several endangered species that once roamed North America, in Yellowstone. It is a National Park and very pretty. It also can blow up totally with virtually no warning, certainly not enough time for humans to capture or herd out all the endangered species we parked there!

Of course, if it blows up really big, we might be the endangered species. This is why volcanists along with astronomers are so vital: they study the real dangers we face aside from our own stupidity.

Culture of Life News Main Page

Hot Spot Volcanic Events Are Filled With Controversy

Click here for origional map from Winds of Change.net

Elaine Meinel Supkis

Just this week, the BBC covered the ongoing volcanic eruptions in Renucion Island which is off Madagasscar. People died in this latest eruption. But this brings us to the issue of 'hot spots' or 'plumes': what are they, why do they happen and why are they the producers of some of the most violent eruptions?

Click here to see BBC clip of volcano erupting in Reunion.

Click here for more BBC pictures of volcano in Reunion.

From This Is London:

But the islanders are used to the spectacle. It is the third eruption of the Piton de la Fournaise or 'Mountain of the Furnace' this year alone.
About 50 teenagers were taken to hospital from three schools in Saint Joseph with respiratory problems caused by the volcano's sulpher fumes, according to Clicanoo.com, the online newspaper of La Reunion.

Researchers on the island are concerned the recent activity may be creating more cracks lower down the volcano, which will allow the molten lava to spread further.

The volcano is about 530,000 years old and has erupted an estimated 170 times since the mid 17th century.

Evidently, tourists photographing one of Nature's more violent emotional states fell into the lava and were burned to nearly nothing in no time at all. One of the most dangerous professions a scientist can go into is the study of these beasts: all too many volcanists die. Especially in the major explosions. For unlike mere lava flows, the most dangerous volcanic events is when a major volcano completely destroys itself in one mighty blast.

The last time in recorded histroy this happened was the great Krakatoa event over 100 years ago. Like all great blasts, the volcano not only vanished in an eyeblink, it left behind a huge ring which we call a caldera. All the great blasts in the past have left these empty rings. Many times, they fill with water from either the ocean, glaciers melting or rainfall. This is a feature of all meteorite strikes too.

An interesting feature is that a much smaller volcano will rise at one end of these lakes which are trapped inside of blown-up volcanoes. And always, the new, 'baby' volcano will be off-set because of the movement of the tectonic plate above. And always, the baby never reaches the dimensions of the older volcano. There is always some sort of pause before a new one begins. No one knows why this is so or how it really works.

From Dinosaur Extinction Pages:

For microscopic shelled animals known as foraminifera, new tran-K-T graphic correlation studies indicate that basal Tertiary stratigraphic successions display "progressive rather than instantaneous turnover in biotic, sedimentologic, and geochemical variables over at least 500,000 years." The impact "scenario fails to account for a large number of physical and biotic observations in both ancient and modern faunas and should be abandoned as a plausible model of tran-K/T events" (MacLeod, 1995).

Deccan Traps volcanic CO2 accumulation in marine waters also accounts for the trans-K-T extinction of both swimmers and organisms living on, or attached to, the ocean floor. Ward (1994) notes these extinctions commenced in phases. The earliest, just below the K-T boundary, involved inoceramid bivalves, reef facies, and other benthic mollusks. The next phase, at the K-T boundary, involved extinction of all the ammonites and the microscopic organisms discussed above. The final phase involved benthic foraminifera during earliest Tertiary time.

Accumulation of CO2 in marine waters is known to produce deleterious effects on many marine animals (Knoll et al., 1996, from which the following is abstracted). Elevated CO2 disrupts the acid-base balance of internal fluids leading to narcotizing acidosis. Increased acidity decreases the oxygen affinity of hemoglobin and other respiratory pigments (Bohr effect); high CO2 levels CO2 binds directly with respiratory pigments, reducing their capacity to carry oxygen. High CO2 levels also produce metabolic reduction and arrest. Animals that produce CaCO3 skeletons are especially sensitive because CO2 interferes with carbonate biomineralization.

One of the biggest 'hot spots' on earth is the one possibly connected with Reunion Island: the long chain of underwater volcanoes which have only a few islands above sea level which march in a straight line north to India. If we drained all the water off the surface of the earth, we would be able to see these straight lines which rise out of a rather depressed sea floor. Namely, the sea bed itself isn't filled with lots of mountains but is a rather flat plain which these mountains rise like classic 'sawtooth' mountains which often come from rifting but in this case, isn't rifting but is the result of the Indian Ocean plate moving rapidly north in nearly a straight line.

The movement of India is most astonishing: unlike most other plates, when the India subcontinent calved off of the Antarctic landmass, it took off like a bullet and shot north, hitting Asia which is moving eastwards in a long, slow arc, slamming into the belly of that great landmass with such forward force, it has raised the tallest mountains on earth which are still rising for this sector hasn't exhausted its momentum yet.

This is a map showing the earth's relative gravity. The lowest point is centered right over the lowest end of India. On the other side of the world's tallest mountains is another, nearly as low, gravity point! Right over Tibet, of all places, the world's highest plateau.

The world's highest gravity point is right next door: the volcanic chain of the islands of Indonesia and all along the leading edge of the same plate that carriest Australia. Australia was next door to India when Pangea broke up. For some unexplainable reason, when the break up began 100 million years ago, India tore away and began its journey while Australia lagged behind, only recently beginning its increasingly violent move, heading rapidly now towards Alaska. Which is curving westards towards Australia, but at a much slower pace.

This schematic drawing of the planet as some geologists believe it might have looked 100 million years ago shows how all the Southern Hemispheric continents might have interacted. I hypothetically placed Reunion's hot spot at the juncture of where Somalia joined the Punjab region of India.

I also drew in the massive meteorite strike that hammered the border between Antarctica and Australia 150 million years earlier. There are many questions this raises. Did this massive strike which possibly killed off most living things back in the Permian Extinction, cause Pangea to break up? If so, why did Australia move away much slower and later than India?

From MSNBC:

An apparent crater as big as Ohio has been found in Antarctica. Scientists think it was carved by a space rock that caused the greatest mass extinction on Earth, 250 million years ago.

The crater, buried beneath a half-mile (1 kilometer) of ice and discovered by some serious airborne and satellite sleuthing, is more than twice as big as the one involved in the demise of the dinosaurs.

The crater's location, in the Wilkes Land region of East Antarctica, south of Australia, suggests it might have instigated the breakup of the so-called Gondwana supercontinent, which pushed Australia northward, the researchers said.

What lurked under the joining of India, Africa and Antarctica? That center point where everything broke apart? Why is the deepest low gravity point associated with the Indian Ocean Plate and India itself INCLUDING TIBET?

From the Journal of Geophysics:

Modelling of gravity data in order to construct the subsurface structure in terms of a density distribution is a time-tested technique of geophysical interpretation and is always relied upon to yield first order information, which is correlatable with observed geological knowledge. Nevertheless gravity models are plagued by the ambiguity of results, which are intrinsic to the mathematical treatment of potential field methods and suffers from increasing uncertainty and diminishing resolution with depth. Simultaneous three dimensional modelling of geoid data in conjunction with gravity data is an advanced interpretation technique, which provides added constraints and helps to reduce uncertainty, particularly in areas where there is a lack of data from other geophysical and/or geological studies.

In the Western Continental Margin of India, this method of interpretation, based on predominantly satellite derived potential field data, allows us to estimate the effects of the various regional scale geological units, viz. the crust, the upper mantle, the underplated magmatic material, low density crustal heterogeneities, etc. On subtraction of these effects from the observed anomalies, we are able to delineate the extent of the Deccan basalts, which was presumably associated with the episode of Reunion hotspot activity under the waters of the Arabian Sea, as far as 800 km from the coastline. Localised basins of low density material beneath the north western Deccan Traps are also resolved.

Namely, if there was, and it looks probable, a hot spot over this particular point in the planet's lithosphere/mantle junction, this was so hot and so powerful, it caused the Indian subcontinent, when it passed over, to create one of the biggest lava events on earth? Namely, the Indian Plate, as the thinner parts moved over, produced merely a long daisy-chain of islands which probably, 100 million years ago, were quite impressive, but when the center of India passed over, it all blew its gaskets and fountains of lava simply poured out, sans volcanoes, simply rent right through and gushed for the entire time India rolled on over this hot spot!

Why didn't it begin blowing up when the northern edge of India passed over? Did the Northern edge miss this spot? If so, I doubt this becaues this part of the continent sticks out! So I would suggest, the hot spot formed BECAUSE India created it AS IT CRAWLED OVER. All the continents 'sag' in the middle. This is why mighty rivers flow in these places: the Mississippi, the Amazon, the Nile, the Rhein and Danubes, the Yellow River, the Mekong, etc. The Dravos, the Volgo, on and on. Including the Ganges and the Indus Rivers.

If you look at a map of India, the Narmada River runs into the bay of the state of Gujarat. The coast of India seems like one, smooth shape like South America, for example, but like South America, there is, in the exact center of the subcontinent's outline, a deep dagger cut where, in South America, a great river seperating Argentina from its neighbors, runs. In India, there is no great river but this is because that sector of the continent isn't really low like the Mississippi valley, for example: it was covered starting right at that juncture, by a huge bed of lava, the Deccan Pans. There is no line of volcanoes north of this point where the lava simply roared out of the earth, I would guess, with terrific, loud violence. All the many creatures living on that continent proabably were instantly killed for many miles around!

We know this happens because the USA is moving over a hot spot which has caused terrific, sudden lava flows in Washington, Idaho and Montana over the eons. Geologists have found the outlines of large grazing mammals caught in these sudden floods of lava which come with little warning besides some considerable shaking of the earth's crust.

When this terrible event happened, there was virtually no ocean between Antarctica and India. In other words, this effusion of lava didn't happen when India began to break off from Antarctica abut after it had moved at least 400 miles northwards or so. When the weakest part of the continent 'snagged' this particular spot, it took off.

So there are several questions here as well as clues:

1. India broke off from Antarctica the same time as South America and Africa but before Australia.

2. A major asteroid/meteorite hit Antactica 100 million years before the other plates began to seriously move away.

3. The plate with India on it 'grew' as India moved northwards and as it grew in size due to Antarctica barely moving at all, as India sped northwards, both India and it became a low-gravity well.

4. As India moved over the Reunion hot spot, the earth's mantle was disgourged and covered half of the continent, weighing it down.

5. This massive event didn't even slow down the rapid move by India heading north.

6. Even when India slammed into Asia, slowing down the northwards movement of that plate, it didn't cause sufficient mountain-building to overcome the gravity loss effect and indeed, the lithosphere under Tibet was so weak, evidently it collapsed into the Mantle!

The Indian craton was once part of the Supercontinent of Pangaea, attached on what is now its west coast to Madagascar and southern Africa. About 160 million years ago during the Jurassic Period, rifting caused Pangaea to break apart, firstly into two supercontinents (Gondwana to the south and Laurasia to the north). The Indian craton for a time remained attached to Gondwana, but this too began to rift apart about in the early Cretaceous, about 125 million years ago, creating the Indian Plate. The Indian Plate then sped northward toward the Eurasian Plate, at a pace that is the fastest movement of any known plate. About 90 million years ago, it separated from Madagascar. The Indian Plate first collided with the Eurasian Plate about 50 million years ago. This collision, which is ongoing today, closed up an intervening sea, then lifted the Himalaya Mountains and the Tibetan Plateau, and caused parts of the Asian continent to deform westward and eastward on either side of the collision. Just before or simultaneous with this collision, the Indian Plate sutured on to the adjacent Australian Plate, forming a new larger plate, the Indo-Australian Plate.
The Deccan Traps

During its journey northward after breaking off from the rest of Gondwana, the Indian Plate passed over a geologic hotspot, the Réunion hotspot, which caused extensive melting underneath the Indian craton. The melting broke through the surface of the craton in a massive flood basalt event, creating what is known as the Deccan Traps. It is also thought that the Reunion hotspot caused the separation by rifting of Madagascar and India.

So these facts lead to many questions:

1. Did the gravity weak sector pre-exist at that spot of the earth?

2. Did this gravity zone which is represented by the color blue, is this a place where the lithosphere is particularily weak?

3. Did an event pre-3 billion years ago, create this huge gravity low point? It does cover several thousand miles.

4. It is suggested the Moon was blasted from the earth in a great collision at that time. Is this the place where the moon came from?

5. Is Earth's mantle permenantly deformed by ancient celestial events from the time when the earth and moon were first forming?

6. Are all the hot spots from this same time frame, predating the formation of the continents?

7. Are the hot spots places where the lithosphere is fatally compromised by the hammering our planet took when all that space debris poured down upon everything in the new star's LaGrange points?

These points make me wonder: are the hot spots that still exist, are they really very, very old and are they DEFORMATIONS of the lithosphere from very ancient debris events? In other words, when the planet was solidifying, wasn't the lithosphere rather maleable? Instead of blowing through it, asteroids would shape it like a smith hammering on steel?

These hot spots are scattered all over the planet and if one looks at detailed maps, they are very, very randomly placed. They are, like all the asteroid events in the past as we see on other planets or the moon, evenly scattered.

There is no earth-geological reason for them to be in the various odd places they inhabit. In the center of the Pacific Plate? Or right off the coast of Africa? Or how about smack in the middle of the Rock Mountains? This is illogical. But if the lithosphere were significantly deformed but NOT BROKEN by hard strikes of mega-rocks 3 billion years ago, these things could form a 'pocket'.

From Search and Discovery:

India was selected as the reference continent since it exhibits the most detailed APWP, having drifted about 50º of latitude since breakup. The paleomagnetic data from all continents exhibit a consistent trend in the form of a narrow envelope for the period representing the "fit" through to the mid-Tertiary. Paleomagnetic poles for the five discrete time intervals of this APWP (Fig. 1), correspond to the finite positions of the continents according to the marine magnetic anomalies at times 115 Ma (Fig. 2A), 80 Ma (Fig. 2B), 65 Ma (Fig. 2C), 53 Ma (Fig. 2D), and 39 Ma (Fig. 2E). The reconstructions corresponding to these specific anomalies are depicted in the animated, or time-slice, sequence (Fig. 2A-2F). Thus, it was demonstrated that currently available paleomagnetic data from the continents are consistent with the history of Gondwana dispersal recorded by marine magnetic anomalies. As a consequence, there was remarkable agreement on an overall reconstruction of Gondwana circa 150 million years ago: in very general terms, the 1937 du Toit (6) and the 1970 Smith-Hallam (8) reconstructions were vindicated.

I suggest clicking on this web-page. Just to see the movie. It shows clearly one possible scenario for the break-up of Pangea. As the continents broke up, they also were moving, en mass, across the planet's surface. The fact that not only continents but mega-continents were in and still are, in constant movement, is quite amazing and frankly, ill-understood. This always takes me to the fact that most of the super-big earthquakes that change the landscape in big ways, happen nearly universally at the 10 km level. There is something going on there we don't really understand yet.

From Space.com:

Using terrestrial evidence and crater evidence from the Moon, which retains a record of bombardment going back nearly 4 billion years, Abbott has analyzed the timing of large impacts compared with major volcanic eruptions, or mantle plumes.

She found a strong correlation between the two and speculates that large impacts strengthen existing mantle plumes. She describes the ancient and dormant Deccan Traps volcanism, an area that is presently part of India. At the time of the Chicxulub asteroid impact, which occurred in Mexico 65 million years ago and likely led to the demise of the dinosaurs, the Deccan Trap region was near the antipode of the impact.

Others have suggested this coincidence could be possible evidence that impact antipode effects initiated the Deccan Traps.

However, Boslough says the Deccan Traps would have been several thousand kilometers away from the antipode to Chicxulub. Abbott says the Deccan Traps were active well before the Chicxulub impact, and so could not have been initiated by that event, but she observes that the Deccan plume was strongest immediately after the impact and this phase lasted less than one million years.

The key here is, they are operational TODAY. And thus, not part of the Mantle! Namely, there is no way these entities could exist after huge continental masses pass over unless they are part of the lithosphere and not the mantle!

This is the classic 'volcano' cut-aways I grew up with. Note how the volcano taps directly into the Mantle! I would say, 'Ouch'! If this were so, our volcano events would all dwarf the Deccan and Siberian pan eruptions and those two amazing events caused mass extinctions!

So I think our volcanoes don't directly tap into the Mantle but are much less direct.

I drew some pictures about this, comparing the old, standard vision of what volcanoes look like if one bisects them with my own idea of what these deformed portions of the lithosphere looks like in reality:

In this drawing, I show a schematic view of the depression, nearly a sack, caused by a meteoroid hitting the still very mallable lithosphere billions of years ago. Just like a smith heats the steel before hammering it, so did these early rocks striking the earth's surface long ago. They peppered it so none of the lithosphere is smooth or even but undulates a great deal. On top of this, the movement of the plates have totally deformed it. We now know this year that huge sections of it have simply detached and collapsed into the Mantle, for example. It is obviously not all that strong particularily after being hammered billions of years ago.

This is a schematic drawing of a typical caldera: these are created by volcanoes blowing up. Why do they do this? And why are these events mostly at hot spots and subduction zones? Again, there are many questions. One thing is certain: the official drawings showing a volcano with a thin thread of magma are not exactly a good example of how this works because all volcanoes that blow up, do so leaving a rim like a meteoroid strike. And the inside is very, very similar indeed except for one thing: a new volcano nearly always forms off to one side, the far side from the leading edge of the moving tectonic plate.

We know from Mt. St. Helen's that far from being a 'mountain' like those many mountains created by folding the crust, volcanoes have now real integrity as mountains, they blow up via their sides or wherever. It is interesting to me, HAHAHA, (arg) that Mt. St. Helen's blew up on the FAR SIDE from the leading side of the North American plate movement, namely, on the east side which is where the new energy center probably is and which is why it will probably end up being blown away just like Crater Lake, for example.

So viewing volcanoes not as mountains but as sand piles covering some hot spot that is activated by the movement of the tectonic plate, it makes it easier to understand why they blow up so hideously and dangerously.

From Yahoo.com:

RANONGGA, Solomon Islands (AFP) - The seismic jolt that unleashed the deadly Solomons tsunami this week lifted an entire island metres out of the sea, destroying some of the world's most pristine coral reefs.

In an instant, the grinding of the Earth's tectonic plates in the 8.0 magnitude earthquake Monday forced the island of Ranongga up three metres (10 foot).

Submerged reefs that once attracted scuba divers from around the globe lie exposed and dying after the quake raised the mountainous landmass, which is 32-kilometres (20-miles) long and 8-kilometres (5-miles) wide.
*snip*
Further north at Niu Barae, fisherman Hendrik Kegala had just finished exploring the new underwater landscape of the island with a snorkel when contacted by the AFP team.

He said a huge submerged chasm had opened up, running at least 500 metres (550 yards) parallel to the coast.

Several surrounding islands sank but one shot up! Amazing. Just like the even greater Boxing Day Event moved a tremendous amount of real estate suddenly by 100 meters or more, this one probably moved the islands, too. And one of them jumped out of the water as Australia continues is much faster pace northwards compared to all the plates surrounding it which are moving, many of them, towards the same point in the planet, where Asia, North America and Australia are doomed to end up, roughly where Hawaii's hot spot sits...oh my.

From Planetary Ley Lines:

Geologists theorize that water and gases trapped in the mantle during the formation of the planet puncture the crust. Water at great pressure and temperature can lower the melting point of silicates by hundreds of degrees. A basic description of planetary volcanism is: Water deep in the crust or mantle.

Water is key in the understanding of orgone. Water is the universal solvent/filter/accumulator of orgone. The same places where water is in motion is where orgone is in motion. Hot Spots are portals into the mantle of the Earth.

There are various numbers for Hot Spots. Most often the number thirty-three is cited. The number is more likely sixty as geologists have omitted most of Asian volcanism as arising from the mantle. Also due to the height of the Himalayas and other mountain ranges, Hot Spots may be hidden at depth but still creating orgone portals.

Recently, I wrote about how scientists have discovered the equivelent of the Arctic Ocean's waters trapped in the lithosphere under Tibet. The land of Tibet used to be under the ocean before India plowed into Asia. The fact that the lithosphere holds water like a sponge is very interesting because this particular part has collapsed into the Mantle yet still has the water embalmed within.

Volcanes blow up. They blow up not because of hot lava like the Reunion hot spot is engorging this week, they explode like bombs. And these events produce tremendous amounts of dust. And we suspect the build-up of gases is due to the interaction of the Mantle with water. But water is a funny substance: it would be totally ineffective as a trigger to explosions unless it is collected somehow.

And I would suggest the deformations from the earliest years, the deformations that made indentations in the lithosphere collect water and protect it from the Mantle but the cracks in the indentations caused by the violence of the impacts allows enough magna from the Mantle to flow into these depressions so they fill up regularily but also fill with water which then forms 'bubbles' that rise to the surface, thus the many minor events before a volcano blows up.

Further, the more the crust moves tectonic plates over these places, the opening for these bubbles to exit begins to CLOSE and when the 'hot spot' is on the further edge of a volcano, it blows up totally, forming a caldera.

Furthermore: when this caldera is created by a mighty explosion, the chamber holding the gasses and water and magma is now no longer under pressure. A small subsidiary can grow but the earth keeps moving while the volcano rests and when there is sufficient pressure again, a new one begins to form.

From Geology.com:

However, there is a body of theory that explains hotspots not as plumes from the deep, but mostly stirrings in the upper mantle—its top 400 kilometers—caused from above by the movements of the crustal plates and surface-based cooling. A 2001 article in Geotimes summarized this school of thought to a wide audience, citing fresh evidence. Clearly the debate is gaining visibility. A more pointed article published by the Geological Society of London in May 2003 continues the attack.

Earth scientist extraordinaire Don L. Anderson (of Caltech) has been a key player in this alternative hotspot hypothesis. He argues that the original hotspot theorists made assumptions about the upper mantle that new facts have overturned—the whole upper mantle is hotter and more fluid than once thought.

Making magma happens easily in the upper mantle, Anderson says, simply by releasing pressure, for example during continental breakups. He traces many hotspots backward in time to starting points at the edges of continents which have since moved away. And he calculates that the insulating effect of thick continental plates builds up heat beneath them, which eventually comes out in hotspots. There is no reason to call for hot magmas from any deeper in the Earth, he believes.

There is a great deal of disagreement about hot spots. I found no definitive expert. Using what little I could find and adding to it my own thoughts which have grown over many years as I have climbed in and out and around many a volcano or lava eruption site, all I know is, we barely have any idea what is going on right under our own feet.

And this makes our own planet most exciting. And the idea that water is vital for volcanic events is enhanced by the fact that all of Mars' volcanoes are dead. But once, when the planet had more water concentrated in greater volume on the surface as well as in the lithosphere, it raised some truly huge volcanoes...but only for a short while.

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Lead Poisoning in Oz

Spring snow storm in Berlin today

Elaine Meinel Supkis

Lead poisoning is in the news again. After 50 years of struggling to stop this pollution, laws were passed in many countries including even Japan only now with all the manufacturing moving into new Asian countries, it is on the rise again even in places where it was outlawed in the past. Also, the victims of the lastest earthquake/tsunami struggle to survive.

From Xinahua Net:

A section of the Honghe River in southwest China's Guangxi Zhuang Autonomous Region has been polluted by lead, and water supply suspended, local authorities confirmed on Thursday.

Excessive lead and other heavy metals were detected in a 100-kilometer section of the Honghe River between the Longtan power station and the Du'anhe River in Dahua Yao Autonomous County. Tests on pollutant levels are underway, and the cause of the pollution is being investigated.

I remember the days before anyone had any serious pollution laws. Rivers in Europe and America were filthy. Every imaginable chemical and poison as well as human waste was simply flushed into our water systems. It was quite a battle, stopping this pollution. I remember when the color of rivers would change as places dying leather or cloth would flush their tanks. Not to mention rivers catching fire!

The tendency of all manufacturing systems is to make profits by disposing wastes carelessly. Careful disposal costs time and money and 'saving' profits by dumping dangerous stuff all over the place or polluting the air is a huge temptation which is why rigorous laws have to be enforced.

When the rest of Asia suddenly joined the industrial race, all the previous protections installed at great cost have begun to collapse because in order to compete, manufacturers have to be wretched house keepers. The degradation is spreading. Note how the USA handed over its own systems to the GOP which is dedicated to profits for the rich, not saving anything at all. Since then, the agencies set up to protect us from pollution have been run by foxes in the hen house, administrators who want to allow pollution.

And it isn't just the USA, this carelessness is spreading.

From the Independent UK:

Local people were alarmed when they came across dead lorikeets, wattlebirds, honeyeaters and silvereyes in their parks and back yards. Health officials told them not to worry. But they tested their rainwater tanks, the main source of drinking water, and found dangerously high levels of lead or nickel in more than a third.

The authorities still insisted there was no cause for concern. Then they tested the seabed at the Esperance port, through which nickel and lead carbonate mined inland are shipped to Asia. Some samples contained 130 times the recommended health levels of the two metals. It was also established that 4,000 birds had died of lead poisoning.

There was lead in the air, lead in the drinking water, and lead in the sea. And when health officials finally admitted that there might cause for concern and began testing the population, they found lead in their blood.

When I first read about the dead birds in Australia several months ago, I waited to see what caused it. I feared it was pollution. For birds are the 'canary in the mine' and they are very sensitive to air pollution or heavy metals. Like bees who are also dying all over the earth, they interact with things we want for ourselves, namely, flowers and seeds, and if something is poisoning these items, the birds die first.

Australia, anxious to make money trading raw materials so they can buy Asian goods, has gotten increasingly careless handling dangerous minerals. Mining is destructive. Gold mining often pollutes rivers with mercury, for example. The tailings from mines often have all sorts of dangerous minerals that are toxic to life forms including humans. When I went to Germany in 1968, I was horrified to see swaths of forest dying from the prevailing winds that carried not only acid rain but other toxins.

Then I came home to America and began to notice pollution here, too. I grew up in pristine places where observatories sit so it was a shock to see places dominated by industries and cities. I knew from visiting LA to see my grandfather, the air was pure poison. It made me physically ill, having grown up in a truly rarified environment!

Rich people who collect the profits of this pollution try to live above it, literally. They own vacation homes in pristine places, if they live in NYY or Paris, they live on the top floors above the street pollution with internal climate systems. They use all sorts of evasions. But Nature has to be cared for, eventually, even the rich will die if the planet is too polluted. If nothing else, from global warming.

From NDTV:

Aid workers helping survivors of a tsunami disaster in the Solomon Islands complained on Thursday that the relief efforts are chaotic and lack resources, warning of growing health risks for thousands left homeless in squalid camps.

"We are under-resourced, we need bigger vehicles," said disaster official Jonathan Taisia at the main Red Cross center in hard-hit Gizo town, as a chartered helicopter landed with the latest load of tarps and food.

But much of the aid coming into Gizo wasn't being distributed beyond depots because of vehicle shortages, and a lack of workers to load trucks or clear debris that has severed road links to outlying villages, he said.

I noticed from photographs that much of the beachfront villages are now underwater. Namely, the land subsided. This seems to happen a lot with big earthquakes. Mountains might go higher but the lowlands can drop off, into the water. Lisbon had this happen several hundred years ago, for example. We still don't understand exactly why this happens but it seems to be common.

The victims of this disaster are very remote from 'civilization'. They are barely noticed in the hub-bub of the news cycle. But we have even forgotten about New Orleans! At least, the people who matter don't think about New Orleans. And none of these poor people married billionaires and then went crazy and died from popping pills, either.

And hurricane season lurks around the corner here. Soon we will be very busy feeling sorry for ourselves, I suspect.

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The Australian Plate Causes Yet Another Mega-Earthquake

Elaine Meinel Supkis

Another major earthquake on the leading edge of the Australian Plate. Australia is rapidly moving north/northeast, shoving over the Pacific Plate, striking it at a 90 degree angle for that plate is moving northwest. And Asia is heading eastwards and the collision points are the island chains of Japan and the Philippines. There are many questions about the Australian Plate's geology.

From Sky News Australia:

Villages and towns in the Solomon Islands have been severely damaged and at least eight people are missing feared dead, after a powerful earthquake in the South Pacific caused a tsunami.

The earthquake struck 350 kilometres north west of Honiara at a depth of 10 kilometres.

Solomon Islands Broadcasting Corporation in Honiara said residents on Simbo Islands had reported waves travelling up to 200 metres inland.

The island of Gizo, a regional centre in the country's west, endured a wave several metres high which flattened houses and caused widespread damage.

Witnesses also reported villagers being washed into the sea.

Image from Sky News TV, Australia.

Once again, villages and towns were suddenly indunated by a tsunami and we won't know how many people were swept away, attempts at setting up tsunami warning systems are hampered by the lack of time one has if an earthquake happens right off shore.

This lastest mega-earthquake is, like the Boxing Day one, involved the fast moving India/Australia plate complex. Both of these land masses once hinged on Antarctica but a great rift opened up between all three of them and first India and then Australia broke loose and the ever-spreading sea floor has propelled them both northwards at a much faster clip than any other tectonic plates.

The 'Ring of Fire' caused by the Pacific Plate being shoved violently westwards by the rifting in the Atlantic Ocean shoving North America westwards causes all the volcanoes and earthquakes in the rim of Asia and North America but the Australian Plate is a totally different agent here: it is driving northeast at a mad clip and has already ridden over a good section of the Pacific Plate which is not being shoved northwards by the Australian Plate at all.

I drew a simple map that shows the general direction of plate movements. Note how North America is moving in a totally different direction from South America. Indeed, it looks like it is cartwheeling in a counter-clockwise motion. Eurasia, on the other hand, is moving in a clockwise direction towards the Pacific.

The question is, why are the two largest land masses on the northern hemisphere moving in a turning motion, towards one spot in the Pacific? We know they are being pushed but why in that particular direction? There is nothing at the North Pole that could be pushing them, is there? Antarctica is nearly totally stationary. Perhaps this is due to the heavy load of ice sitting on top. The earth isn't round and we have a moon that has enough gravitational pull to yank the huge oceans into high and low tides that are quite obvious on the ground.

We also have a widening Atlantic Ocean that is smaller than the Pacific. The weight of the oceans, the thinness of the ocean floors, the lithosphere, all these things affect the movement of the plates.

From Livescience:

From temporary lunacy to werewolf awakenings, the lunar cycle has seen its share of blame. Now, scientists say that the different phases of the moon influence the flow of a massive ice stream in Antarctica.

The Rutford Ice Stream—a river of ice larger than the Netherlands which drains the West Antarctic Ice Sheet—varies its speed by almost 20 percent every two weeks, scientists report in the Dec. 21 issue of the journal Nature.

The change coincides to the bi-weekly tidal cycle when the gravitational pull of the Moon and the Sun are either working together or working against each other.

The moon causes tides. It also exerts enough force to change the movements of ice flowing in glaciers. So I would assume it affects the earth. This latest mega-earthquake occured during the full moon phase. The moon used to be closer to Earth long ago. Over the eons, it has moved away yet even though it is not that huge.

The Boxing Day event was on a winter solstice full moon. This event was right before Easter, the full moon of the Spring Equinox. Looking at the other planets, one can't help but notice they are not like our earth. We know that the tidal pull of the Jovian giants heat up their moons but perhaps because our moon is so big compared to our own size, it has caused our own planet to stay hot?

For Mars is a geologically dead planet with two very minor moons that can't do much. The earth's surface probably oozed and moved about so forcefully due to the pull of the moon as it caused the water on the planet's surface to shove the continents and cause cracks in the lithosphere that would allow the hot magma of the mantle to escape and pour forth.

Perhaps our fractured surface was caused by lunar tides? And everything is lopsided due to the fluidity of the oceans? This brings to mind a new thought: during the last 5 million years, during the increasing Ice Ages, were the Northern continents pinned down by the ice and did this slow them down while Australia and India were both free of ice and free of Antarctica, the landmass they calved off from---did they and Africa move freely while the rest of the planet slowed down?

Is this why they are still moving forcefully even as both crashed into or are skirting past, Asia? And Africa is moving into Eurasia so forcefully, it is splitting apart on the east coast, cut by the Arabian Penninsula like a cake being cut by a sharp knife?

Looking at this simplified gravity map I drew, it is interesting to see that the main 'hot spots' are where Australia is riding up over the Pacific Plate and has deformed the southern edge of the Asian Plate very badly, there is severe subduction zones along the entire front as the Australian Plate slides under Asia even as Australia slides OVER the Pacific Plate. The world's biggest earthquakes and some of the most active volcanoes are along this subduction zone. Yet Australia itself is serene with no volcanoes and no earthquakes.

Why is this? The gravity map also shows interesting things like the fact that the lithosphere on either side of the Himalayans has collapsed. Geologists last month suggested the lithosphere fell away entirely under the Tibetan Plateau. This looks like it should be a good analysis.

The other place where the crust is very thin is the Indian Ocean right below India. This weak spot is very noticable, it is part of the Australian plate and it is one of the biggest thin areas on earth. This seems odd to me since it is also being shoved relentlessly and rather swiftly, under Asia. One would imagine it would be bulking up due to hitting something hard.

Here is the gravity map of Australia. It is quite interesting that the western half is 'thin crust' with a hidden element: looks like the remains of a subduction zone in the southwest corner. According to some geologists, the western half of the continent was dry land while the eastern half was under water. Yet the eastern half, in these gravity data pictures, is the denser sector and the middle of the western half is thinner? A riddle indeed.

One wonders if the lithosphere fell there, causing the land to spring up over the Pacific Plate? What I mean is, the dense lithosphere on the half riding next to Southeast Asia has been very stressed by this and the lithosphere seperated and now the western half of Australia is riding up over the plates that are moving in the opposite direction? There are some older fault lines along the Southwestern Wales.

I also wonder if these gravity maps show past asteroid hits? From before there was life on earth, even.

The complex earth is very challengeing to understand and geologists have a really fun job, figuring out what is going on. The theories abound. This latest huge earthquake happened at that interesting depth of 10 km. The Boxing Day Tsunami occured on that depth, too. Many important quakes are at that depth.

So what is going on there between the crust and the lithosphere?

From the National Academy of Sciences:

Steven E. Ingebritsen*, and Craig E. Manning

Nearly all of our data below about 10-km depth represent permeability during prograde (heating stage) metamorphism. This finding suggests that the deeper part of this k-z curve is most applicable to regions where the crust is being thickened and/or heatedthat is, to orogenic belts. There appears to be a causal link between fluid sourcing and permeability in tectonically active crust (9, 10); for example, metamorphic devolatilization reactions likely generate porosity waves that progagate upward through the crust from the zone of fluid liberation (13). In the absence of a fluid phase, permeability and porosity in the middle and lower crust may be exceedingly small. Thus we expect lower permeabilities during cooling and decompression, or in the deep crust in stable cratons, where there is no active metamorphism.

It has been proposed that there is a hydrologic seal or that permeability decreases markedly at the brittle-ductile transition (14-16), which occurs at 10- to 15-km depth in crustal rocks under geothermal gradients typical of regional metamorphism. Such behavior would retard or prevent transfer of fluids from the deep crust and mantle to the upper crust and hydrosphere. However, our data indicate a change in slope of the permeability-depth relation near the brittle-ductile transition, rather than an abrupt decrease in permeability. The log fit to the data (Fig. 1A) shows permeability decaying by about an order of magnitude below the brittle-ductile transition, but the data below about 12.5 km are actually fitted just as well by a constant permeability of 1018.3 m2 (Fig. 1B).

We know the moon has a lot of influence on the more fluid parts of our earth not to mention the bodies of all living things that have fluid which is why us females, for example, are in thrall to the moon and are aware of it's moods and quirks. So of course, the fluidity and temperature of the planet itself responds to the moon as well as the sun, of course, our ultimate ruling force.

From Blackwell Synergy:

The brittle–ductile transition has been suggested to provide a mechanical trap to deep crustal fluids. The mechanism was advanced as a way of reconciling the geophysical case for a wet lower crust, founded on the revelation of deep crustal electrical conductors and seismic reflectors, with the problem of maintaining interconnected, low-density fluids in stable crust for geologically significant timescales. Although some deep crustal conductors are now attributed to graphite, the hypothesis of fluid trapping at the brittle–ductile transition has been widely adopted in electromagnetic literature, with no regard to tectonic regime, and in association with standardized temperatures of 300–450°C. Meanwhile, petrologists continue to argue that the lower crust is dry.

This paper re-examines the arguments on which the hypothesis of fluid trapping at the brittle–ductile transition has been founded, and concludes that there is a geophysical case for a dry lower crust based on electromagnetic studies. The magnetotelluric (MT) technique yields electrical conductances (conductivity–thickness products) that are direction dependent (or anisotropic). The necessity of considering direction-dependent conductances, rather than a bulk conductance, is demonstrated using data from Saxothuringia, Germany. A quantitative model is developed to facilitate joint interpretation of the maximum conductance and the anisotropy of conductance (ratio of maximum to minimum conductance). The model yields quantitative arguments against fluids being the principal cause of deep crustal electrical conductivity, because unreasonably thick layers and unreasonably high porosities are required.

So the degree of vicosity and fluidity of this important level of the earth's crust is in full debate. I cannot judge which makes more sense and hope to see more data as researchers probe our own planet.

10 km seems to be a point where the fluidity of crustal rocks changes, it is where water and minerals can still vacillate between several states. Obviously, when earthquakes happen, there has to be some fluidity below or it woudn't happen.

I can't print up either of theses document above but they are interesting reading. I always wondered why most major quakes happen at that depth more often than any other. Thin crust or thick, it is the same.

Here is a difficult to read but intriguing paper by two geologists who think Australia is unique:

Eric Debayle, Brian Kennett & Keith Priestley

Institut de Physique du Globe de Strasbourg, Ecole et Observatoire des Sciences de la Terre, Centre National de la Recherche Scientifique and Université Louis Pasteur, 61084 Strasbourg, Cedex, France

The depth configuration of azimuthal anisotropy beneath Australia in the depth range 150–300 km is similar to that beneath oceans in the depth range 50–200 km but shifted downward by 100 km. Except in the upper 100 km, Australia is completely different from other continents, which display a gentle decrease of anisotropy from 1.4% at 50 km to about 0.6% at 300 km depth.

Further, Australia is the only continental plate where azimuthal anisotropy correlates significantly with present-day plate motion. This peculiar behaviour of the Australian continent is highlighted in the global correlation (Fig. 3) between azimuthal anisotropy and the present-day absolute plate motion (APM). Fast anisotropy directions beneath Australia do not correlate with APM at depths shallower than 150 km, but show strong correlation from 150 km to 300 km depth with a maximum near 200 km. This agrees with previous regional surface wave tomography for the continent

.
None of the other continents show significant plate-scale correlation between anisotropic directions and APM. The anisotropic signature of the Australian plate is similar to that observed at shallower depths beneath oceans. In young oceanic regions where the lithosphere is expected to be thin, significant correlation between anisotropy and APM is observed at 50 km depth (Fig. 3) and extends over large regions around the mid-ocean ridges beneath the Pacific, Indian and Atlantic Oceans. At 100 and 150 km depth, the regions where anisotropy correlates with APM shift to the old oceanic basins. This shift suggests that the depth of plate-motion-induced deformation increases with the age of the sea floor and the thickness of the oceanic lithosphere.

Figure 2b shows the average correlation between APM and fast anisotropic directions calculated for Australia, other continents, and oceanic basins. The strong correlation between Australian anisotropy and APM is prominent between 150 and 300 km depth. The fast direction beneath the oceans displays, on average, a weaker correlation with APM between 100 and 250 km depth. This weaker correlation between oceanic anisotropy and APM can be related to the observation.

Our results therefore suggest that the Australian plate is the only continental plate whose motion is fast enough to produce large scale deformation at its base. The slower horizontal motion of other continental plates may produce smaller basal deformation, and thus a larger proportion of olivine crystals with a plunging axis of symmetry and a weaker azimuthal anisotropy. At depths greater than 220 km, enrichment in clinopyroxene may also contribute to the vanishing of anisotropy

I wonder if India was like Australia? It is from the same vector and moved at tremendous speed, much faster than anything else around it. Why would that happen? It nearly split in two before hitting Asia. The Deccan Traps are from a rift that opened, not from a collision but being yanked apart! This filled with lava and it killled of a tremendous number of life-forms across the planet.

Perhaps the base of Australia (and India) were detached from the lithosphere allowing them to flow with minimal friction? One can only guess. What we do know is, the leading edge of Australia is causing mountain building via volcanoes. But the buckling of the continent's leading edge is minor compared to the leading edge of North America that is violently buckling under the stress of trying to crash over the Pacific Plate, indeed, it is probably shoving that plate westards at a good clip, considering. Except this doesn't explain much of anything!

Why is the Pacific Plate moving so swiftly into Asia? It hits Asia and slides under with great violence. We know that Eurasia is moving towards the Pacific thanks to the Atlantic rifting. But why is it cartwheeling to this one point in the ocean that happens to be the same spot Australia is determined to head into? If I were looking at this as a dynamic system on a flat surface, I would suspect there is some magnetic force at work, if this were concave, I would suspec that is the lowest point.

But this is a globe and there is no singular reason for all the northern landmasses to move towards that spot. Heh. Maybe I should call it 'The Great Attractor' in honor of that mega-complex of galaxies that our own is heading towards at break neck speed!

From the Australian Solid Mechanics Research Group:

It seems very reasonable to suppose that when sea levels rise or fall, they do so by the same amount everywhere - water after all finds its own level. Surprisingly, this is not the case in Australia. 120 million years ago, Eastern Australia was flooded with water creating a huge inland sea. Yet this flooding occured at a time when sea levels around the world were relatively low. To add to the confusion, Australia lost its inland seas about 70 million years ago when elsewhere around the world, sea levels were at their highest.

*snip*
In 1998, Mike Gurnis from Caltech, Dietmar Müller from Sydney University, and I set out to solve the Australian flood conundrum using the modeling approach I have outlined. We took all the information which Dietmar Müller had compiled for the way the Australian plate had moved over the past 100 Million Years and combined this with a 3 dimensional model of the mantle which included cold slabs of lithosphere like the one shown in Figure 2.

We discovered that Australia passed over one of these slabs over one hundred million years ago as it was drifting Northward and Westward in response to far-reaching mantle flow patterns. 120 Million years ago, when Australia was considerably further South than it is today, and still attached to Antartica, the oceanic lithosphere to the East of Australia was sinking into the mantle and dragging down the Eastern half of Australia by up to three hundred metres - enough to cause widespread flooding despite globally low sea levels.

In Figure 3 the dark blue on the map of the Australian continent show our prediction of the flooded areas. Flooding persisted until about 60 million years ago. At this point, the sinking lithosphere was several hundred kilometers down in the mantle and its effect on the continent was beginning to weaken. At about this time Australia began to separate from Antarctica and move Northward. As it escaped from the influence of the sinking lithosphere, Eastern Australia popped back up again. Now, however, it was covered with a layer of sediments and stood higher than it had before the flooding occured. (Newly flooded land immediately starts to accumulate a layer of sediments from the erosion of nearby high-ground and from the action of the small creatures that live in the water).

This was enough to prevent the same areas from flooding again when global sea levels rose. What became of the sinking slab ? Most of it is now deep in the mantle where it is barely detectable by seismological probing. However, a small part of it was dragged near to the surface when Australia and Antarctica split apart. Today the ancient slab is located in between the two continents where it sucks the ocean floor down, causes very unusual patterns on the seafloor and an obvious change in the chemical makeup of the seafloor - a mysterious region known as the Australian-Antarctic discordance (or AAD for short). Our prediction of the location of this remnant of lithosphere is marked by the centre of the purple ellipse in the final frame of Figure 3; it is remarkably close to the true position of the AAD.

Yet another sinking lithosphere moment. I would suggest that far from uncommon, this is normal. Namely, our shattered lithoshpere, first banged up most terribly by some ancient collision, the one that created the moon, never go to form a solid like the ones on Mars and Venus not to mention the moon itself. All the planets and moons were hammered by space objects of various sorts to the point that the moon, for example, is wall to wall craters, but these didn't crack the lithospheres of the other planets and I would again, suggest the moon is responsible for keeping things cracked up here.

And every time a meteorite or asteroid or comet slams into the earth, the shaking this causes, especially when they hit the ocean or on a rift zone, can widen these cracks and activate them. The theories of these two geologists are intersting but don't refer to the gravity maps and this is the problem with theories: one has to include lots and lots of data and not leave out unhappy bits that don't fit.

And I think very few things explain Australia, why it is zooming northwards with such ferocity and why it is so 'quiet' geologically even as it is causing much of the earth to spasm with pain and annoyance. Why the earth is splitting along the Atlantic Central Ridge and between Antarctica and the India/Australian plates is a mystery still. Why are these areas so active? Why are they so powerful? What on earth is going on down there, the place earlier people called 'Hell'?

Who the hell knows.

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