Long-term variations in volcanism help explain the birth, evolution and death of striking geological features called oceanic core complexes on the ocean floor, says geologist Dr Bram Murton of the National Oceanography Centre, Southampton.Oceanic core complexes are associated with faults along slow-spreading mid-ocean ridges. They are large elevated massifs with flat or gently curved upper surfaces and prominent corrugations called 'megamullions'. Uplifting during their formation causes exposure of lower crust and mantle rocks on the seafloor.
New evidence has made it more likely that remnants of Martian microbes were transported to Earth in a meteorite, it was revealed today. A study by scientists from the American space agency Nasa has found chemical signatures in the rock strongly associated with life.The discovery strengthens the case for believing that worm-like structures in the meteorite are 'microfossils' of ancient Martian bugs.
The Congo Basin -- with its massive, lush tropical rain forest -- was far different 150 million to 200 million years ago. At that time Africa and South America were part of the single continent Gondwana. The Congo Basin was arid, with a small amount of seasonal rainfall, and few bushes or trees populated the landscape, according to a new geochemical analysis of rare ancient soils.
The strikingly banded rocks scattered across the upper Midwest and elsewhere throughout the world are actually ambassadors from the past, offering clues to the environment of the early Earth more than 2 billion years ago. A study offers a new picture of how these colorful bands developed and what they reveal about the composition of the early ocean floor, seawater, and atmosphere during the evolution of the Earth.
In 1980, Luis Alvarez and his collaborators stunned the world with their discovery that an asteroid impact 65 million years ago probably killed off the dinosaurs and much of the the world's living organisms. Now, researchers from MIT and their collaborators have found that at least some forms of microscopic marine life - the so called "primary producers," or photosynthetic organisms such as algae and cyanobacteria in the ocean - recovered within about a century after the mass extinction. Previous research had indicated the process might have taken millions of years.
Princeton University scientists have shown that, in ancient times, the Earth's magnetic field was structured like the two-pole model of today, suggesting that the methods geoscientists use to reconstruct the geography of early land masses on the globe are accurate. The findings may lead to a better understanding of historical continental movement, which relates to changes in climate.
Scientists at the Carnegie Institution have found a way to monitor the strength of geologic faults deep in the Earth. This finding could prove to be a boon for earthquake prediction by pinpointing those faults that are likely to fail and produce earthquakes. Until now, scientists had no method for detecting changes in fault strength, which is not measureable at the Earth's surface.
Researchers have discovered an unusual kind of meteorite in the Western Australian desert and have uncovered where in the Solar System it came from, in a very rare finding published in the journal Science. Meteorites are the only surviving physical record of the formation of our Solar System and by analysing them researchers can glean valuable information about the conditions that existed when the early Solar System was being formed. However, information about where individual meteorites originated, and how they were moving around the Solar System prior to falling to Earth, is available for only a dozen of around 1100 documented meteorite falls over the past two hundred years.
