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We know that true polar wander (TPW) can occasionally tilt whole planets and moons relative to their axes, but it's not entirely clear just how often this has happened to Earth. Now a new study presents evidence of one such tilting event that occurred around 84 million years ago – when dinosaurs still walked the Earth. Researchers analyzed limestone samples from Italy, dating back to the Late Cretaceous period (100.5 to 65.5 million years ago), looking for evidence of shifts in the magnetic record that would point towards an occurrence of TPW. Bacteria fossils trapped in the rock, forming chains...

Scaglia Rossa Limestone exposed near Furlo, Italy, in the Northern Apennine Mountains. Limestone at this locality accumulated on the bottom of a shallow sea, in an arm of the ancient Mediterranean ocean nearly 85 million years ago, during what is called Late Cretaceous time. Credit: Ross Mitchell.Hold on to your hats, because scientists have found more evidence that Earth tips over from time to time. We know that the continents are moving slowly due to plate tectonics, but continental drift only pushes the tectonic plates past each other. It has been debated for the past few decades whether the...

During the experiment, 26 participants each sat with their eyes closed in a dark, quiet chamber lined with electrical coils. These coils manipulated the magnetic field inside the chamber such that it remained the same strength as Earth’s natural field but could be pointed in any direction. Participants wore an EEG cap that recorded the electrical activity of their brains while the surrounding magnetic field rotated in various directions. ...Joseph Kirschvink, a neurobiologist and geophysicist at Caltech, and colleagues studied alpha waves to determine whether the brain reacts to changes in magnetic field direction. Alpha waves generally dominate EEG readings...

I wrote last week about the coming Grand Solar Minimum, something that will have much more impact on the environment than anything we puny humans can do. It generated a lot of interest from all sides, so it’s time to delve deeper into what we can expect. Starting with the hype: During the last grand solar minimum (GSM), the Maunder Minimum of 1645 to 1715, glaciers advanced, rivers froze, sea ice expanded -- in short, the Little Ice Age. Is another one is almost upon us? Probably not. Maunder occurred at the tail end of a bi-millennial cycle. These cycles...

Findings also suggest exoplanets lying within habitable zones may be susceptible to ice ages. ============================================================================= At least twice in Earth’s history, nearly the entire planet was encased in a sheet of snow and ice. These dramatic “Snowball Earth” events occurred in quick succession, somewhere around 700 million years ago, and evidence suggests that the consecutive global ice ages set the stage for the subsequent explosion of complex, multicellular life on Earth. Scientists have considered multiple scenarios for what may have tipped the planet into each ice age. While no single driving process has been identified, it’s assumed that whatever triggered...

Like any spinning object, Earth is subject to centrifugal force, which tugs on the planet's fluid interior. At the equator, where this force is strongest, Earth is more than 26 miles larger in diameter than at the poles. Gordon said true polar wander may occur when dense, highly viscous bumps of mantle build up at latitudes away from the equator. If the mantle anomalies are massive enough, they can unbalance the planet, and the equator will gradually shift to bring the excess mass closer to the equator. The planet still spins once every 24 hours and true polar wander does...

In our planet's early history, 720 to 640 million years ago, thick sheets of ice covered the majority of the surface, as the Earth was locked in a deep freeze. But explosive underwater volcanoes changed the chemistry of the Earth's oceans and were key to breaking the planet from its icy state, according to a new study. Researchers at the University of Southampton believe underwater volcanoes helped to thaw out "Snowball Earth", and even led to runaway chemical chain reactions, which created the conditions for an explosion of life on Earth. While much of the driving forces behind glaciation during...

American boffins say they have discovered evidence that almost the entire world was covered in sea ice and glaciers at certain points in the remote past, during so-called "snowball Earth" periods where the polar ice sheets met at the Equator. It were grim in the old days. Geologists probing conditions seen in the ancient world have long considered that there was a cold spell known as the Sturtian Glaciation about 716 million years ago. However there has been disagreement in boffinry circles as to just how severe this glaciation was. Now, researchers from Harvard uni in the States, funded by...

A 250-million-year shutdown of volcanic activity which is thought to have occurred early in Earth's history may be what turned the planet into a glacier-covered snowball. It could also have helped give rise to our oxygen-rich atmosphere. Previous studies have noted that very little volcanic material has been dated to between 2.45 and 2.2 billion years ago, but it was widely assumed the gap would vanish as more samples were dated. Now an analysis of thousands of zircon minerals collected from all seven continents indicates that the gap may be real after all. Zircons provide a record of past volcanic...

Enlarge ImageMolecular fingerprints. Sedimentary rock formations in Oman, like this one, contain chemical evidence of the planet's first animals, which appeared at least 635 million years ago. Credit: David Fike, Nature Where did all the animals come from? The fossil record is virtually animal-free up until the Cambrian Explosion 540 million years ago, and then--boom--thousands of critters of all shapes and sizes show up. The mystery has plagued scientists for more than a century and a half, beginning with Charles Darwin. Now, with a brilliant bit of detective work, researchers have located our missing ancestors. The problem with the...

A sudden and extreme case of runaway global warming 635 million years ago was caused by an abrupt release of methane, a powerful greenhouse gas, scientists said today. The methane seeped from ice sheets that covered much of the planet toward the end of a frigid era called Snowball Earth. The gas escaped gradually at first and then very quickly from clathrates, or methane ice that forms and stabilizes beneath water ice sheets. As the water ice melted, pressure was relieved on the clathrates and they began to de-gas. The transition represents one of the earliest known cases of what...

Source: University of Chicago Date: February 5, 2007 Ancient Rocks Show How Young Earth Avoided Becoming Giant Snowball Science Daily — A greenhouse gas that has become the bane of modern society may have saved Earth from completely freezing over early in the planet's history, according to the first detailed laboratory analysis of the world's oldest sedimentary rocks. A rock from a banded iron formation in northern Quebec, Canada. The bands vary in thickness from approximately 10 microns (less than the width of a human hair), to 10 meters (30 feet). This sample is measures a few inches across. At...

Scientists based in Germany and Norway today published new results about a geophysical theory known as true polar wander. That is a drifting of Earth's solid exterior -- an actual change in latitude for some land masses -- relative to our planet's rotation axis. These scientists used hotspots in Earth's mantle as part of a computer model, which they say is accurate for the past 120 million years, to identify four possible instances of true polar wander in the past. And, they say, true polar wander is happening now... The scientists -- including Pavel V. Doubrovine and Trond H. Torsvik...

Geoscientists in Scotland say they have evidence to disprove the controversial "Snowball Earth" theory - the idea that the planet was completely encased in ice just over 600 million years ago.We are claiming that in reality there was not a totally frozen snowball Earth and that even during the coldest conditions large regions remained ice-free -- Dr Dan CondonThe team, from the University of St Andrews, has published its findings in the scientific journal Geology, after studying rocks in the west of Scotland, Ireland, Namibia and California. Drs Dan Condon, Tony Prave and Doug Benn say they have found evidence...

New Haven, Conn. — The Gondwana supercontinent underwent a 60-degree rotation across Earth’s surface during the Early Cambrian period, according to new evidence uncovered by a team of Yale University geologists. Gondwana made up the southern half of Pangaea, the giant supercontinent that constituted the Earth’s landmass before it broke up into the separate continents we see today. The study, which appears in the August issue of the journal Geology, has implications for the environmental conditions that existed at a crucial period in Earth’s evolutionary history called the Cambrian explosion, when most of the major groups of complex animals rapidly...

PASADENA, Calif.— Roughly a billion years from now, the ever-increasing radiation from the sun will have heated Earth into inhabitability; the carbon dioxide in the atmosphere that serves as food for plant life will disappear, pulled out by the weathering of rocks; the oceans will evaporate; and all living things will disappear. Or maybe not quite so soon, say researchers from the California Institute of Technology (Caltech), who have come up with a mechanism that doubles the future lifespan of the biosphere—while also increasing the chance that advanced life will be found elsewhere in the universe. A paper describing their...

WASHINGTON: A new research has found that prehistoric global cooling that started in Antarctica about 35.5 million years ago, was caused by a sharp drop in the carbon dioxide (CO2) levels. Even after the continent of Antarctica had drifted to near its present location, its climate was subtropical. Then, 35.5 million years ago, ice formed on Antarctica in about 100,000 years, which is an "overnight" shift in geological terms. "Our studies show that just over thirty-five million years ago, 'poof,' there was an ice sheet where there had been subtropical temperatures before," said Matthew Huber, assistant professor of earth and...

<p>Conveyor of a super-Einsteinian theory of gravitation that explains, among many other post-Einstein-effects, the Sun-Earth-Connection and the true cause of the global climate changes.</p> <p>As the glaciological and tree ring evidence shows, climate change is a natural phenomenon that has occurred many times in the past, both with the magnitude as well as with the time rate of temperature change that have occurred in the recent decades. The following facts prove that the recent global warming is not man-made but is a natural phenomenon.</p>

The findings, from two separate research groups... say the process of carbon sequestration is already underway. Even so, the new carbon sink is unlikely to make a significant dent in the huge amounts of CO2 pumped into the atmosphere by industrial activities... Phytoplankton produce chlorophyll to obtain energy from the sun and assimilate CO2, and so increased phytoplankton productivity would remove more carbon from the atmosphere... From one year to the next, the phytoplankton grew more in areas where the ice had disappeared: less ice meant more open water for longer, allowing the plankton to soak up more energy from...

The climate orthodoxy of carbon hysteria has never understood the intricacies of causative interaction in Earth's climate. Led by fanatics such as James Hansen and Al Gore, the orthodoxy decided early on to assign responsibility for "climate change" to human generated CO2. Orthodoxers reduced the complex system of climate to a single parameter--CO2--to make their job easier. Unfortunately, the orthodoxy failed to recruit (bribe and cudgel) large numbers of mathematically and scientifically trained men and women who remain curious about the underlying complexity of climate. Curious enough to continue studying climate as a multi-causative system. The distribution of sunlight, rather...