Changes in the earth's magnetic field in a region that stretches from the Atlantic to the Indian Ocean have a close relationship with variations of gravity in this area. Because geophysicists can follow these changes using highly accurate measurements from certain satellites, they can make conclusions about what is happening in the Earth’s outer core.
A U.K. research team has recently determined that the geometry of channels beneath the ice can be a strong control on ice behaviour, temporarily hiding the signals of retreat. The findings, which provide the first simulation of past ice-sheet retreat and collapse over a ten thousand year period in Antarctica, shed new light on what makes ice stable or unstable and will help refine predictions of future ice extent and global sea-level rise, the researchers say.
For the first time, three separately found extreme Earth events have been compared by researchers who now believe they may be linked. About 41,000 years ago, a complete and rapid reversal of the geomagnetic field occurred, lasting for just a few hundred years. Around the same time, a super volcano erupted and major climate changes occurred.
The most likely source of the water locked inside soils on the moon's surface is the constant stream of charged particles from the sun known as the solar wind, a University of Michigan researcher and his colleagues have concluded. Over the last five years, spacecraft observations and new laboratory measurements of Apollo lunar samples have overturned the long-held belief that the moon is bone-dry.
Two instruments on the Mars rover Curiosity were used to study the chemical makeup of a football-size rock called "Jake Matijevic". In addition to the ChemCam, which had examined a number of rocks, NASA for the first time used an X-ray spectrometer on the new rock, finding that its composition resembles some unusual rocks found in Earth’s interior.
The NASA rover Curiosity has beamed back pictures of bedrock that suggest a fast-moving stream, possibly waist-deep, once flowed on Mars. There have been previous signs that water existed on the red planet long ago, but the images released Thursday showing pebbles rounded off, likely by water, offered the most convincing evidence so far of an ancient streambed.
It sounds like an artifact from an Indiana Jones film; a 1,000 year-old ancient Buddhist statue which was first recovered by a Nazi expedition in 1938 has been analysed by scientists and has been found to be carved from a meteorite. The findings reveal the priceless statue, which is the first known carving of a human in a meteorite, to be a rare class of meteorite that fell 15,000 years ago.
Scientific deep sea drilling vessel “Chikyu” has set a world new record by drilling down and obtaining rock samples from deeper than 2,111 m (6,926 feet) below the seafloor off Shimokita Peninsula of Japan in the northwest Pacific Ocean. “Chikyu” is designed to reach the deeper part of the Earth such as the mantle, the plate boundary seisomogenic zones and the deep biosphere.
A multi-institutional team led by scientists at Lawrence Berkeley National Laboratory have directly observed electron hopping in iron oxide particles, a phenomonon that holds huge significance for a broad range of environment- and energy-related applications.
Scientists using the Mini-RF radar on NASA's Lunar Reconnaissance Orbiter have successfully estimated the maximum amount of ice likely to be found inside a permanently shadowed lunar crater located near the moon's South Pole. Their results, which offer more definite support to prior findings, show as much as 5 to 10% of the material, by weight, could be patchy ice.
If recent research by a team from the U.S. and Germany is correct, previous estimates about the total mass of all life on planet Earth will have to be reduced by about one third. The revision came about after researchers realized that previous drill cores, upon which the estimate are based, were recovered close to shore or in nutrient-rich areas. However, much of the ocean is a “desert”, supporting very little life.
Recent studies of small, repeating, and very frequent earthquakes in an Antarctic ice sheet may not only lead to a better understanding of glacial movement, according to Penn State University geoscientists, but may also shed light on stick slip earthquakes like those on the San Andreas fault or in Haiti.
A recent finding by a University of Nebraska-Lincoln research team shows that Moqui marbles, unusual balls of rock that can be found rolling around the southwestern U.S. sandstone regions, were formed roughly 2 million years ago with the help of microorganisms. Previous theories of their formation had suggested a chemical reaction devoid of life, but clear evidence of life’s role has been discovered.
Our family tree may have sprouted some long-lost branches going back nearly 2 million years. A famous paleontology family has found fossils that they think confirm their theory that there are two additional pre-human species besides the one that eventually led to modern humans.
The Barnett Shale is a geological formation in North Texas bearing a large amount of natural gas that was difficult to recover prior to recent technological advances such as hydraulic fracturing. A geophysicist at the University of Texas at Austin analyzed seismic data over a two-year period and has found that while proving any one earthquake was caused by drilling is impossible, a connection between earthquake frequency and fracking does exist.
In the years after Columbus’ voyage, burning of New World forests and fields diminished significantly, and some have claimed the decimation of native populations by European diseases are to blame. But a new study suggests global cooling resulted in fewer fires because both preceded Columbus in many regions worldwide. In effect, the researchers report, they have found a link between climate and fire.
A group of geoscientists studying the behavior of the Earth’s geomagnetic field have recently discovered that on a time scale of tens to hundreds of millions of years, the field itself may be influenced by currents in the mantle. These thermal flows could also be connected to frequent polarity reversals that have taken place in Earth’s past.
Debate over the origin of large-scale polygons (often many kilometers in diameter) on Mars has been intensified by comparison to similar geometric patterns on Earth. Geologists at The University of Texas at Austin have recently examined these polygons and compared them to similar features on Earth's seafloor, which they believe may have formed via similar processes.
Researchers analyzing meteorite fragments that fell on a frozen lake in Canada have developed an explanation for the origin of life's handedness—why living things only use molecules with specific orientations. The work also gave the strongest evidence to date that liquid water inside an asteroid leads to a strong preference of left-handed over right-handed forms of some common protein amino acids in meteorites.
Recent volcanic eruptions have demonstrated our continued vulnerability to ash dispersal, which can disrupt the aviation industry and cause billions of dollars in economic loss. Volcanic particle size is determined by the initial fragmentation process, when bubbly magma deep in the volcano changes into gas-particle flows. Recent laboratory experiments and computer simulations of this particle breakup, known as granular disruption, sheds light on the type of fragmentation likely to produce fine-grained ash.
The powerful magnitude-8.6 earthquake that shook Sumatra on April 11, 2012, was a seismic standout for many reasons, not the least of which is that it was larger than scientists thought an earthquake of its type could ever be. Now, researchers from the California Institute of Technology report on their findings from the first high-resolution observations of the underwater temblor, they point out that the earthquake was also unusually complex
Research by the National Physical Laboratory (NPL) and the University of Bradford used laser microscopes to explore how stone tools were used in prehistory, and the process has helped streamline surface measurement techniques for modern manufacturers.
In 1969, an exploding fireball tore through the sky over Mexico, scattering thousands of pieces of meteorite across the state of Chihuahua. More than 40 years later, the Allende meteorite is still serving the scientific community as a rich source of information about the early stages of our solar system's evolution. Recently, scientists from the California Institute of Technology discovered a new mineral embedded in the space rock—one they believe to be among the oldest minerals formed in the solar system.
Previous research the Carnegie Institution’s Bob Hazen demonstrated that up to two thirds of the known types of minerals on Earth can be directly or indirectly linked to biological activity. Now, he has traced the history of one mineral of interest—mercury—and has shown the changes in Earth’s geochemistry that contributed to the formation of the 90 or more mercury-containing chemical now found on Earth.
After analyzing the longest sediment cores ever retrieved on land, obtained from beneath remote, ice-covered Lake El'gygytgyn ("Lake E") in the northeastern Russian Arctic, researchers say the polar regions are much more vulnerable to climate change than previously thought. The cores reveal intense warm climate intervals in the Arctic’s recent past.