by Linnaeus University, May 9, 2017 in ScienceDaily
It is becoming more and more appreciated that a major part of the biologic activity is not going on at the ground surface, but is hidden underneath the soil down to depths of several kilometres in an environment coined the « deep biosphere ». Studies of life-forms in this energy-poor system have implications for the origin of life on our planet and for how life may have evolved on other planets, where hostile conditions may have inhibited colonization of the surface environment. The knowledge about ancient life in this environment deep under our feet is extremely scarce.
by University of Bristol, September 9, 2011 in ScienceDaily
Ultra high precision analyses of some of the oldest rock samples on Earth provides clear evidence that the planet’s accessible reserves of precious metals are the result of a bombardment of meteorites more than 200 million years after Earth was formed.
by UNSW Sydney, May 9, 2017 in ScienceDaily
Fossils discovered by UNSW scientists in 3.48 billion year old hot spring deposits in the Pilbara region of Western Australia have pushed back by 580 million years the earliest known existence of microbial life on land.
he Pilbara deposits are the same age as much of the crust of Mars, which makes hot spring deposits on the red planet an exciting target for our quest to find fossilised life there.”
by McGill University , EPSL, May 5, 2017, in ScienceDaily
Conventional theory holds that all of the early Earth’s crustal ingredients were formed by volcanic activity. Now, however, earth scientists have published a theory with a novel twist: some of the chemical components of this material settled onto Earth’s early surface from the steamy atmosphere that prevailed at the time.
More than 90% of Earth’s continental crust is made up of silica-rich minerals, such as feldspar and quartz. But where did this silica-enriched material come from? And could it provide a clue in the search for life on other planets?
by University of Maryland, in Nature, February 27, 2017
New research suggests that plate tectonics began later in Earth’s history
But new research suggests that this was not always the case. Instead, shortly after Earth formed and began to cool, the planet’s first outer layer was a single, solid but deformable shell. Later, this shell began to fold and crack more widely, giving rise to modern plate tectonics.
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