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Categories: Geoscience: Earthquakes, Geoscience: Geology

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For many hundreds of millions of years, the average temperature at the surface of the Earth has varied by not much more than 20 degrees Celsius, facilitating life on our planet. To maintain such stable temperatures, Earth appears to have a 'thermostat' that regulates the concentration of atmospheric carbon dioxide over geological timescales, influencing global temperatures. The erosion and weathering of rocks are important parts of this 'thermostat.'

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A team has collected dozens of samples from across southeastern Colorado, and their results could help to answer an enduring mystery: What made Colorado's High Plains so high?

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Massive volcanic events in Earth's history that released large amounts of carbon into the atmosphere frequently correlate with periods of severe environmental change and mass extinctions. A new method to estimate how much and how rapidly carbon was released by the volcanoes could improve our understanding of the climate response, according to an international team.

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New research documents the fastest-known large-scale breakage along an Antarctic ice shelf. A 6.5-mile crack formed in 2012 over 5-and-a-half minutes, showing that ice shelves can effectively shatter -- though the speed is limited by seawater rushing in. The results help inform large-scale ice sheet models and projections of future sea level rise.

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Researchers are revisiting old building practices -- the use of by-products and cast-offs -- as a way to improve building materials and sustainability of the trade. A technique known as rammed earth construction uses materials that are alternatives to cement and are often more readily available in the environment. One such alternative is wood fly ash, a by-product of pulp mills and coal-fired power plants.

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A detailed survey of the volcanic underwater deposits around the Kikai caldera in Japan clarified the deposition mechanisms as well as the event's magnitude. As a result, the research team found that the event 7,300 years ago was the largest volcanic eruption in the Holocene by far.

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Researchers have devised a way to remotely detect large landslides within minutes of occurrence and to quickly determine whether they are close to open water and present a tsunami hazard.

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A new measure that compares earthquake-related fatalities to a country's population size concludes that Ecuador, Lebanon, Haiti, Turkmenistan, Iran and Portugal have experienced the greatest impact from fatalities in the past five centuries.

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Our planet's lithosphere is broken into several tectonic plates. Their configuration is ever-shifting, as supercontinents are assembled and broken up, and oceans form, grow, and then start to close in what is known as the Wilson cycle.

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A new study offers a glimpse into the possible impact of climate change on coastal wetlands 50 years or longer into the future. Scientists are usually forced to rely on computer models to project the long-term effects of rising seas, but an unexpected set of circumstances enabled a real-world experiment along the Gulf Coast.

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This study reports widespread mineral carbonation of mantle rocks in an oceanic transform fueled by magmatic degassing of CO2. The findings describe a previously unknown part of the geological carbon cycle in transform faults that represent one of the three principal plate boundaries on Earth. The confluence of tectonically exhumed mantle rocks and CO2-rich alkaline basalt formed through limited extents of melting characteristic of the St. Paul's transform faults may be a pervasive feature at oceanic transform faults in general. Because transform faults have not been accounted for in previous estimates of global geological CO2 fluxes, the mass transfer of magmatic CO2 to the altered oceanic mantle and seawater may be larger than previously thought.

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Researchers have uncovered the first direct evidence that the West Antarctic Ice Sheet shrunk suddenly and dramatically at the end of the Last Ice Age, around eight thousand years ago. The evidence, contained within an ice core, shows that in one location the ice sheet thinned by 450 meters -- that's more than the height of the Empire State Building -- in just under 200 years.

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Rocks once buried deep in ancient subduction zones -- where tectonic plates collide -- could help scientists make better predictions of how these zones behave during the years between major earthquakes, according to a research team.

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Inspired during field work in South Australia's Flinders Ranges, geoscientists have proposed that all-time low volcanic carbon dioxide emissions triggered a 57-million-year-long global 'Sturtian' ice age.

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A more accurate way of identifying underground nuclear tests, including those conducted in secret, has been developed.

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The Seattle fault zone is a network of shallow faults slicing through the lowlands of Puget Sound, threatening to create damaging earthquakes for the more than four million people who live there. A new origin story, proposed in a new study, could explain the fault system's earliest history and help scientists improve hazard modeling for the densely populated region.

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The Circumpolar Current works as a regulator of the planet's climate. Its origins were thought to have caused the formation of the permanent ice in Antarctica about 34 million years ago. Now, a study has cast doubt on this theory, and has changed the understanding of how the ice sheet in Antarctic developed in the past, and what this could mean in the future as the planet's climate changes.

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Geoscientists have uncovered a missing link in the enigmatic story of how the continents developed- - a revised origin story that doesn't require the start of plate tectonics or any external factor to explain their formation. Instead, the findings rely solely on internal geological forces that occurred within oceanic plateaus that formed during the first few hundred million years of Earth's history.

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Hydrothermal vents and manganese nodule fields in the deep oceans contain more biodiversity than expected.

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The Hayabusa2 mission that collected samples from the asteroid Ryugu has provided a treasure trove of insights into our solar system. After analyzing samples further, a team of researchers have unearthed evidence that cometary organic matter was transported from space to the near-Earth region.