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Categories: Geoscience: Geology, Geoscience: Volcanoes
Published Below the surface: Researchers uncover reasons to rethink how mountains are built
(via sciencedaily.com) Original source A study suggests that the answers to how and why mountains form are buried deeper than once thought. Clues in the landscape of southern Italy allowed researchers to produce a long-term, continuous record of rock uplift, the longest and most complete record of its kind.
Published Researchers cultivate archaea that break down crude oil in novel ways
(via sciencedaily.com) Original source The seafloor is home to around one-third of all the microorganisms on the Earth and is inhabited even at a depth of several kilometers. Only when it becomes too hot does the abundance of microorganisms appear to decline. But how, and from what, do microorganisms in the deep seafloor live? How do their metabolic cycles work and how do the individual members of these buried communities interact? Researchers have now been able to demonstrate in laboratory cultures how small, liquid components of crude oil are broken down through a new mechanism by a group of microorganisms called archaea.
Published Petit-spot volcanoes involve the deepest known submarine hydrothermal activity, possibly release CO2 and methane
(via sciencedaily.com) Original source Underwater volcanism and its hydrothermal activity play an important role in marine biogeochemical cycles, especially the carbon cycle. But the nature of hydrothermal activity at 'petit-spot' volcanoes have not been revealed at all. Now, scientists reveal that petit-spot hydrothermal activity occurs on the deepest seafloor known to date and could release carbon dioxide (CO2) and methane, which may have implications for the global carbon cycle.
Published Ground beneath Thwaites Glacier mapped
(via sciencedaily.com) Original source The ground beneath Antarctica's most vulnerable glacier has now been mapped, helping scientists to better understand how it is being affected by climate change. Analysis of the geology below the Thwaites Glacier in West Antarctica shows there is less sedimentary rock than expected -- a finding that could affect how the ice slides and melts in the coming decades.
Published River erosion can shape fish evolution
(via sciencedaily.com) Original source A new study of the freshwater greenfin darter fish suggests river erosion can be a driver of biodiversity in tectonically inactive regions.
Published Iron-rich rocks unlock new insights into Earth's planetary history
(via sciencedaily.com) Original source A new study suggests iron-rich ancient sediments may have helped cause some of the largest volcanic events in the planet's history.
Published New method predicts extreme events more accurately
(via sciencedaily.com) Original source A new study has used global storm-resolving simulations and machine learning to create an algorithm that can deal separately with two different scales of cloud organization: those resolved by a climate model, and those that cannot be resolved as they are too small. This new approach addresses the missing piece of information in traditional climate model parameterizations and provides a way to predict precipitation intensity and variability more precisely.
Published Extinct offshore volcano could store gigatons of carbon dioxide
(via sciencedaily.com) Original source A new study concludes that an extinct volcano off the shore of Portugal could store as much as 1.2-8.6 gigatons of carbon dioxide, the equivalent of ~24-125 years of the country's industrial emissions. For context, in 2022 a total of 42.6 megatons (0.0426 gigatons) of carbon dioxide was removed from the atmosphere by international carbon capture and storage efforts, according to the Global CCS Institute. The new study suggests that carbon capture and storage in offshore underwater volcanoes could be a promising new direction for removal and storage of much larger volumes of the greenhouse gas from the atmosphere.
Published Eruption of Tonga underwater volcano found to disrupt satellite signals halfway around the world
(via sciencedaily.com) Original source Researchers found that the Hunga-Tonga eruption was associated with the formation of an equatorial plasma bubble in the ionosphere, a phenomenon associated with disruption of satellite-based communications. Their findings also suggest that a long-held atmospheric model should be revised.
Published Past climate change to blame for Antarctica's giant underwater landslides
(via sciencedaily.com) Original source Scientists found weak, biologically-rich layers of sediments hundreds of meters beneath the seafloor which crumbled as oceans warmed and ice sheets declined. The landslides were discovered in the eastern Ross Sea in 2017, by an international team of scientists during the Italian ODYSSEA expedition, and scientists revisited the area in 2018 as part of the International Ocean Discovery Program (IODP) Expedition 374 where they collected sediment cores to understand what caused them.
Published Physicists take the temperature of fluid flows and discover new role for turbulence
(via sciencedaily.com) Original source A team of physicists has discovered a new role for a specific type of turbulence -- a finding that sheds light on fluid flows ranging from the Earth's liquid core to boiling water.
Published 'Warm Ice Age' changed climate cycles
(via sciencedaily.com) Original source Approximately 700,000 years ago, a 'warm ice age' permanently changed the climate cycles on Earth. During this exceptionally warm and moist period, the polar glaciers greatly expanded. A research team identified this seemingly paradoxical connection. The shift in the Earth's climate represents a critical step in our planet's later climate development.
Published Out of this world control on Ice Age cycles
(via sciencedaily.com) Original source A research team, composed of climatologists and an astronomer, have used an improved computer model to reproduce the cycle of ice ages (glacial periods) 1.6 to 1.2 million years ago. The results show that the glacial cycle was driven primarily by astronomical forces in quite a different way than it works in the modern age. These results will help us to better understand the past, present, and future of ice sheets and the Earth's climate.
Published Great Basin: History of water supply in one of the driest regions in the USA
(via sciencedaily.com) Original source An international team has reconstructed the evolution of groundwater in the Great Basin, USA -- one of the driest regions on Earth -- up to 350,000 years into the past with unprecedented accuracy. The results shed new light on the effects of climate change on water supply and provide important insights for the sustainable use of groundwater resources.
Published How life and geology worked together to forge Earth's nutrient rich crust
(via sciencedaily.com) Original source Around 500 million years ago life in the oceans rapidly diversified. In the blink of an eye -- at least in geological terms -- life transformed from simple, soft-bodied creatures to complex multicellular organisms with shells and skeletons. Now, research has shown that the diversification of life at this time also led to a drastic change in the chemistry of Earth's crust -- the uppermost layer we walk on and, crucially, the layer which provides many of the nutrients essential to life.
Published New clues about the rise of Earth's continents
(via sciencedaily.com) Original source New research deepens the understanding of Earth's crust by testing and ultimately eliminating one popular hypothesis about why continental crust is lower in iron and more oxidized compared to oceanic crust. The iron-poor composition of continental crust is a major reason why vast portions of the Earth's surface stand above sea level as dry land, making terrestrial life possible today. The study uses laboratory experiments to show that the iron-depleted, oxidized chemistry typical of Earth's continental crust likely did not come from crystallization of the mineral garnet, as a popular explanation proposed in 2018.
Published Ridgecrest faults increasingly sensitive to solid Earth tides before earthquakes
(via sciencedaily.com) Original source Faults in the Ridgecrest, California area were very sensitive to solid earth tidal stresses in the year and a half before the July 2019 Ridgecrest earthquake sequence.
Published Turkey's next quake: Research shows where, how bad -- but not 'when'
(via sciencedaily.com) Original source Using remote sensing, geophysicists have documented the massive Feb. 6 quake that killed more than 50,000 people in Eastern Turkey and toppled more than 100,000 buildings. Alarmingly, researchers found that a section of the fault remains unbroken and locked -- a sign that the plates there may, when friction intensifies, generate another magnitude 6.8 earthquake when it finally gives way.
Published Plate tectonic processes in the Pacific and Atlantic during the Cretaceous period have shaped the Caribbean region to this day
(via sciencedaily.com) Original source Earthquakes and volcanism occur as a result of plate tectonics. The movement of tectonic plates themselves is largely driven by the process known as subduction. The question of how new active subduction zones come into being, however, is still under debate. An example of this is the volcanic Lesser Antilles arc in the Caribbean. A research team recently developed models that simulated the occurrences in the Caribbean region during the Cretaceous, when a subduction event in the Eastern Pacific led to the formation of a new subduction zone in the Atlantic. The computer simulations show how the collision of the old Caribbean plateau with the Greater Antilles arc contributed to the creation of this new Atlantic subduction zone. Some 86 million years ago, the triggered processes subsequently resulted in a major mantle flow and thus to the development of the Caribbean large igneous province.
Published 2022 Tongan volcanic explosion was largest natural explosion in over a century, new study finds
(via sciencedaily.com) Original source The 2022 eruption of a submarine volcano in Tonga was more powerful than the largest U.S. nuclear explosion, according to a new study. The 15-megaton volcanic explosion from Hunga Tonga-Hunga Ha'apai, one of the largest natural explosions in more than a century, generated a mega-tsunami with waves up to 45-meters high (148 feet) along the coast of Tonga's Tofua Island and waves up to 17 meters (56 feet) on Tongatapu, the country's most populated island.