by P. Sternal et al., 2017 in NatureGeoscience
Significant and fast reductions in sea level unload the lithosphere, which can increase the production and eruption of magma. Here we calculate variations in surface load associated with the Messinian salinity crisis and compile the available time constraints for pan-Mediterranean magmatism.
by Europlanet Media Centre, September 21, 2017 in ScienceDaily
Diamonds may be ‘forever’ but some may have formed more recently than geologists thought. A study of 26 diamonds, formed under extreme melting conditions in the Earth’s mantle, found two populations, one of which has geologically ‘young’ ages. The results show that certain volcanic events on Earth may still be able to create super-heated conditions previously thought to have only existed early in the planet’s history before it cooled. The findings may have implications for diamond prospecting.
See also here
by University of Manchester, September 11, 2017 in ScienceDaily
The international team, including palaeontologist from The University of Manchester, found a new set of trace fossils left by some of the first ever organisms capable of active movement. Trace fossils are the tracks and burrows left by living organisms, not physical remains such as bones or body parts.
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by Gerard D. Gierlinski et al., August 31, 2017 in Proc.Geologist’sAssoc.
We describe late Miocene tetrapod footprints (tracks) from the Trachilos locality in western Crete (Greece), which show hominin-like characteristics. They occur in an emergent horizon within an otherwise marginal marine succession of Messinian age (latest Miocene), dated to approximately 5.7 Ma (million years), just prior to the Messinian Salinity Crisis.
by University of Chicago Press Journals, August 30, 2017 in ScienceDaily
To date, about 1.5 million species have been formally described in the scientific literature, most of them insects. Proportionally, bacteria comprise less than 1% of all described species.
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In a new paper published in The Quarterly Review of Biology (September 2017), researchers from the University of Arizona have estimated that there are roughly 2 billion living species on Earth, over a thousand times more than the current number of described species.
by Haijun Song et al., August 2017, in Nature
Banded iron formations were a prevalent feature of marine sedimentation ~3.8–1.8 billion years ago and they provide key evidence for ferruginous oceans. The disappearance of banded iron formations at ~1.8 billion years ago was traditionally taken as evidence for the demise of ferruginous oceans, but recent geochemical studies show that ferruginous conditions persisted throughout the later Precambrian, and were even a feature of Phanerozoic ocean anoxic events.
by Ruhr-Universitaet-Bochum, August 22, 2017 in ScienceDaily
Researchers have used computer simulations to analyse how plate tectonics have evolved on Earth over the last three billion years. They show that tectonic processes have changed in the course of the time, and demonstrate how those changes contributed to the formation and destruction of continents. The model reconstructs how present-day continents, oceans and the atmosphere may have evolved.
by National Center for Atmospheric Research/University Corporation for Atmospheric Research, August 21, 2017 in ScienceDaily
Tremendous amounts of soot, lofted into the air from global wildfires following a massive asteroid strike 66 million years ago, would have plunged Earth into darkness for nearly two years, new research finds. This would have shut down photosynthesis, drastically cooled the planet, and contributed to the mass extinction that marked the end of the age of dinosaurs.
by David Middleton, August 18, 2017 in WUWT
If “the supervolcano threat is substantially greater than the asteroid or comet threat,” does this mean we can stop fretting about Gorebal Warming and the Sixth Mass Extinction? Is NASA really moving on to actual threats to the planet? Well, not threats to the planet… The planet has handled supervolcanoes, asteroids and comets quite well over its 4.5 billion year lifespan.
by Jochen J. Brocks et al., August 2017, in Nature
The ‘Rise of Algae’ created food webs with more efficient nutrient and energy transfers, driving ecosystems towards larger and increasingly complex organisms. This effect is recorded by the concomitant appearance of biomarkers for sponges and predatory rhizarians, and the subsequent radiation of eumetazoans in the Ediacaran period.
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by Oregon State University, August 15, 2017 in ScienceDaily
A Triceratops or Tyrannosaurus rex bulling its way through a pine forest likely dislodged flowers that 100 million years later have been identified in their fossilized form as a new species of tree.
by Elsevier SciTech Connect, August 2017
Since 1600, 278,880 people have been killed by volcanic activity, with many of these deaths attributed to secondary hazards associated with the main eruption. Starvation killed 92,000 following the 1815 Tambora eruption in Indonesia, for example, and a volcanic tsunami killed 36,000 following the 1883 Krakatoa eruption.
Research shows that volcanic activity has shown no let up since the turn of the 21st century – it just hasn’t been around population centres. Indeed, there remain a number of volcanoes poised to blow which pose a major threat to life and livelihood.
by David Middleton, August 4, 2017 in WUWT
An article just published in the Proceedings of the Royal Society B describes two remarkably different hydrothermal vent fields discovered in the southern Gulf of California. Despite being relatively close together, these vents host very different animal communities. This finding contradicts a common scientific assumption that neighboring vents will share similar animal communities. Instead, the new paper suggests that local geology and the chemistry of the vent fluids are important factors affecting vent communities
See aslo here
by Tom Raimondo, July 21, 2017 in ABC Science
Australia is often thought of as an ancient and quiescent continent — the sleeping giant in a world where landscapes dramatically change in front of our very eyes.
by David Cox, July 24, 2017 in BBC Future
In the Bay of Naples, Europe’s most notorious giant is showing signs of reawakening from its long slumber.
Campi Flegrei, a name that aptly translates as “burning fields”, is a supervolcano. It consists of a vast and complex network of underground chambers that formed hundreds of thousands of years ago, stretching from the outskirts of Naples to underneath the Mediterranean Sea. About half a million people live in Campi Flegrei’s seven-mile-long caldera, which was formed by vast eruptions 200,000, 39,000, 35,000 and 12,000 years ago.
by Peggy Townsend, July 18, 2017 in PHYS.ORG
The discovery pushed back the time for the emergence of microbial life on land by 580 million years and also bolstered a paradigm-shifting hypothesis laid out by UC Santa Cruz astrobiologists David Deamer and Bruce Damer: that life began, not in the sea, but on land.
by Martin Schobben et al., July 2014,
The Permian geologic period that ended the Paleozoic era climaxed around 252 million years ago with a sweeping global mass extinction event in which 90 to 95 percent of marine life became extinct. It would take 30 million years for planetary biodiversity to recover. Understanding the contributing factors of the end-Permian mass extinction is critical to understanding and perhaps mitigating the current anthropogenic climate change.
by Imperial College London, July 17, 2017, in ScienceDaily
The discovery by researchers from Imperial could lead to a range of improvements including advances in Carbon Capture and Storage (CCS). This is where industrial emissions will be captured by CCS technology, before reaching the atmosphere, and safely stored in rock deep underground.
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by Penn State, July 13, 2017 in ScienceDaily
Large, robust, lens-shaped microfossils from the approximately 3.4 billion-year-old Kromberg Formation of the Kaapvaal Craton in eastern South Africa are not only among the oldest elaborate microorganisms known, but are also related to other intricate microfossils of the same age found in the Pilbara Craton of Australia, according to an international team of scientists.
by University of Oregon, July 10, 2017 in ScienceDaily
Volcanic eruptions such as Mount St. Helens’ in 1980 show the explosiveness of magma moving through the Earth’s crust. Now geologists are excited about what uplifted granite bodies such as Yosemite’s El Capitan say about magma that freezes before it can erupt on the surface.
by Linnaeus University, July 4, 2017
In addition to the life on the surface of the Earth and in its oceans, ecosystems have evolved deep under us in a realm coined the “deep biosphere” which stretches several kilometers down into the bedrock. Down there, the conditions are harsh and life is forced to adjust to a lifestyle that we at the surface would call extreme. One major difference to surface conditions is the lack of oxygen; a compound we take for granted and consider to be a prerequisite for survival but which subsurface life has to cope without.
Original article here (Nature Communication)
by University of Cambridge, June 28, 2017 in ScienceDaily
Using a technique called ‘seismic noise interferometry’ combined with geophysical measurements, the researchers measured the energy moving through a volcano. They found that there is a good correlation between the speed at which the energy travelled and the amount of bulging and shrinking observed in the rock. The technique could be used to predict more accurately when a volcano will erupt. Their results are reported in the journal Science Advances.
by Prof. A. Collins and PhD A. Merdith, June 27, 2017
Earth is estimated to be around 4.5 billion years old, with life first appearing around 3 billion years ago.
To unravel this incredible history, scientists use a range of different techniques to determine when and where continents moved, how life evolved, how climate changed over time, when our oceans rose and fell, and how land was shaped. Tectonic plates – the huge, constantly moving slabs of rock that make up the outermost layer of the Earth, the crust – are central to all these studies.
Along with our colleagues, we have published the first whole-Earth plate tectonic map of half a billion years of Earth history, from 1,000 million years ago to 520 million years ago.
by University of Oxford, June 19, 2017, in ScienceDaily
Huge pulses of volcanic activity are likely to have played a key role in triggering the end Triassic mass extinction, which set the scene for the rise and age of the dinosaurs, new Oxford University research has found.
by M. Dormant and G. Wörheide, June 12, 2017 in Sci.Rep. Nature
According to our results, all non-bilaterian phyla, as well as total-group Bilateria, evolved in an ancient radiation during a geologically relatively short time span, before the onset of long-term global glaciations (“Snowball Earth”; ~720–635 Ma). Importantly, this result appears robust to alterations of a number of important analytical variables, such as models of among-lineage rate variation and sets of fossil calibrations used.