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.
See also here
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 James Edward Kamis, January 19, 2017 in ClimateChangeDispatch
Progressive bottom melting and break-up of West Antarctica’s seafloor hugging Larsen Ice Shelf is fueled by heat and heated fluid flow from numerous very active geological features, and not climate change.
by Donn Dears, July 2017
Here is a summary of the graph’s salient points:
- The CO2 safe limit for US Navy submarines is 8,000 ppm (Dotted red line)
- The CO2 safe limit for the space station is 5,000 ppm (Dotted blue line)
- A line depicting the gradual doubling of CO2 is near the bottom of the graph
- The minimum atmospheric CO2 requirements to sustain plant growth is 150 ppm (Dotted green line)
In addition, atmospheric CO2 has been as high as 7,000 ppm approximately 550 million years ago, and as high as 2,000 ppm as recently as 150 million years ago. (Also here in French)
What the graph clearly shows is how close mankind came to extinction when atmospheric CO2 levels dropped to 183 ppm during the last ice age.
by Dennis T. Avery, June 30, 2017 in WUWT
Carbon dioxide truly is “the gas of life.” The plants that feed us and wildlife can’t live without inhaling CO2, and then they exhale the oxygen that lets humans and animals keep breathing.
Our crop plants evolved about 400 million years ago, when CO2 in the atmosphere was about 5000 parts per million! Our evergreen trees and shrubs evolved about 360 million years ago, with CO2 levels at about 4,000 ppm. When our deciduous trees evolved about 160 million years ago, the CO2 level was about 2,200 ppm – still five times the current level.
See also here (in French)
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 AFP/UKnews, June 21, 2017
Norway on Wednesday proposed to open up a record number of blocks in the Barents Sea to oil exploration despite protests from environmentalists and others fearing possible damage to the Arctic region.
The Norwegian oil and energy ministry offered oil companies 93 blocks in the Barents Sea and nine others in the Norwegian Sea, all located beyond the Arctic Circle.
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.
by Peter Brannen, June 14, 2017
“It is absolutely critical to recognize that I am NOT claiming that humans haven’t done great damage to marine and terrestrial [ecosystems], nor that many extinctions have not occurred and more will certainly occur in the near future. But I do think that as scientists we have a responsibility to be accurate about such comparisons.”
Many popular science articles take this as a given, and indeed, there’s something emotionally satisfying about the idea that humans’ hubris and shortsightedness are so profound that we’re bringing down the whole planet with us.
by Ryan Mandelbaum, June 8, 2017
Rocks alone seem to show that the breakup happened 180 million years ago. But a team of Australian scientists think that you should be able to see the split and continuing shifts written into the history of how animals have evolved. So that’s what the researchers did, and they accomplished this by analyzing a large group of species’ evolution and compared them to the date of the breakup of Pangea.
by Arthur Viterito, April 25, 2016 in J. of Earth Sc. & Climatic Change
Earth’s climate is a remarkably “noisy” system, driven by scores of oscillators, feedback mechanisms, and radiative forcings. Amidst all this noise, identifying a solitary input to the system (i.e., HGFA MAG4/6 seismic activity as a proxy for geothermal heat flux) that explains 62% of the variation in the earth’s surface temperature is a significant finding. Additionally, the 1997/1998 SIENA was a strong signal for subsequent global warming, and this type of seismic jump may provide valuable predictive information
by Sam W. Heads et al., June 7, 2017, in PLOS/One
A new fossil mushroom is described and illustrated from the Lower Cretaceous Crato Formation of northeast Brazil. Gondwanagaricites magnificus gen. et sp. nov. is remarkable for its exceptional preservation as a mineralized replacement in laminated limestone, as all other fossil mushrooms are known from amber inclusions. Gondwanagaricites represents the oldest fossil mushroom to date and the first fossil mushroom from Gondwana.
by Arizona State University, S.H. Shim et al., June 5, 2017, in ScienceDaily
As slabs of Earth’s crust decend into the mantle, they encounter a zone about 1,100 kilometers down where the mantle rock abruptly becomes stiffer, flowing less easily. Similarly, rising plumes of molten rock encounter the same layer and have difficulty punching through from below.
by American Society of Agronomy, May 31, 2017 in ScienceDaily
In the western United States 160,000 abandoned mines contaminate soils in the region. Researchers hope to solve this problem with biochar, a charcoal-like substance that can reduce the toxic consequences of mining for metals.
by Kenneth Richard, May 22, 2017
It has long been established in the peer-reviewed scientific literature that naturally-driven fluctuations in the Earth’s surface temperature preceded the rise and fall of carbon dioxide (CO2) concentrations for at least the last 800,000 years.
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 University of Tromso, May 5, 2017 in ScienceDaily
Bedrock of Earth got severely beaten up by hothouse climate conditions during one of planet’s mass extinctions some 200 million years ago. But the process also allowed life to bounce back.
The hothouse conditions of this mass extinction caused oceans to eventually become depleted of oxygen, and thus become unbearable to live in. But weathering of silicate in the bedrock of Pangea, and subsequent formation of carbonate, tied up the CO2 into the minerals, slowly removing the greenhouse gas from the atmosphere.
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
in ScienceDaily
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.