Geologists are letting the air out of a nagging mystery about the development of animal life on Earth.
Scientists have long speculated as to why animal species didn’t flourish sooner, once sufficient oxygen covered the Earth’s surface. Animals began to prosper at the end of the Proterozoic period, about 800 million years ago — but what about the billion-year stretch before that, when most researchers think there also was plenty of oxygen? (more…)
Antarctica’s topography began changing from flat to fjord-filled starting about 34 million years ago, according to a new report from a University of Arizona-led team of geoscientists.
Knowing when Antarctica’s topography started shifting from a flat landscape to one with glaciers, fjords and mountains is important for modeling how the Antarctic ice sheet affects global climate and sea-level rise. (more…)
PASADENA, Calif. — NASA’s Kepler mission scientists have discovered a new planetary system that is home to the smallest planet yet found around a star similar to our sun.
The planets are located in a system called Kepler-37, about 210 light-years from Earth in the constellation Lyra. The smallest planet, Kepler-37b, is slightly larger than our moon, measuring about one-third the size of Earth. It is smaller than Mercury, which made its detection a challenge. (more…)
COLUMBUS, Ohio — Though scientists have long believed that complex organic molecules couldn’t survive fossilization, some 350-million-year-old remains of aquatic sea creatures uncovered in Ohio, Indiana, and Iowa have challenged that assumption.
The spindly animals with feathery arms—called crinoids, but better known today by the plant-like name “sea lily”—appear to have been buried alive in storms during the Carboniferous Period, when North America was covered with vast inland seas. Buried quickly and isolated from the water above by layers of fine-grained sediment, their porous skeletons gradually filled with minerals, but some of the pores containing organic molecules were sealed intact. (more…)
Jay Dickson and Jim Head have gathered time-lapse photography and other data about the sustained salinity of Antarctica’s Don Juan Pond, the most saline natural body of water on earth. Their findings, published online in Scientific Reports, suggest that such ponds could be possible on Mars.
PROVIDENCE, R.I. [Brown University] — Antarctica’s Don Juan Pond might be the unlikeliest body of water on Earth. Situated in the frigid McMurdo Dry Valleys, only the pond’s high salt content — by far the highest of any body of water on the planet — keeps it from freezing into oblivion. (more…)
The Rio Grande Rift, a thinning and stretching of Earth’s surface that extends from Colorado’s central Rocky Mountains to Mexico, is not dead but geologically alive and active, according to a new study involving scientists from the University of Colorado Boulder’s Cooperative Institute for Research in Environmental Sciences.
“We don’t expect to see a lot of earthquakes, or big ones, but we will have some earthquakes,” said CU-Boulder geological sciences Professor Anne Sheehan, also a fellow at CIRES. The study also involved collaborators from the University of New Mexico, New Mexico Tech, Utah State University and the Boulder-headquartered UNAVCO. The Rio Grande Rift follows the path of the Rio Grande River from central Colorado roughly to El Paso before turning southeast toward the Gulf of Mexico. (more…)
*Berkeley Lab scientists join their KamLAND colleagues to measure the radioactive sources of Earth’s heat flow*
What spreads the sea floors and moves the continents? What melts iron in the outer core and enables the Earth’s magnetic field? Heat. Geologists have used temperature measurements from more than 20,000 boreholes around the world to estimate that some 44 terawatts (44 trillion watts) of heat continually flow from Earth’s interior into space. Where does it come from?
Radioactive decay of uranium, thorium, and potassium in Earth’s crust and mantle is a principal source, and in 2005 scientists in the KamLAND collaboration, based in Japan, first showed that there was a way to measure the contribution directly. The trick was to catch what KamLAND dubbed geoneutrinos – more precisely, geo-antineutrinos – emitted when radioactive isotopes decay. (KamLAND stands for Kamioka Liquid-scintillator Antineutrino Detector.) (more…)
*Krafla volcano gives geologists unique, unexpected opportunity to study magma*
Geologists drilling an exploratory geothermal well in 2009 in the Krafla volcano in Iceland met with a big surprise: underground lava, also called magma, flowed into the well at 2.1 kilometers (6,900 feet) depth.
It forced the scientists to stop drilling. (more…)
