Phys.org July 23, 2024 Vanadium and scandium levels of arc magma served as key indicators in the geochemical models. By compiling global geochemical data from Cenozoic arc magma and olivine-hosted melt inclusions, researchers at the University of Arizona found a latitude-dependent redox distribution of arc magma with less oxidized magma in lower latitudes compared to those in higher latitudes. Based on their work the researchers proposed that such a latitude-dependent pattern in the arc mantle may be controlled by the variation in the redox state of subducted sediment, possibly related to a latitudinal variation in the primary production of phytoplankton, […]
Category Archives: Geoscience
An ocean inside the Earth? Water is determined to be hundreds of kilometers down
Phys.org September 27, 2022 An international team of researchers (USA – Gemological Institute of America, Purdue University, University of Wisconsin, Italy, Germany) analyzed a rare diamond, from Botswana, formed 660 meters below the Earth’s surface confirming that ocean water accompanies subducting slabs and thus enters the transition zone (TZ). This means that our planet’s water cycle includes the Earth’s interior. The immense pressure in the TZ causes the olive-green mineral olivine, which constitutes about 70% of the Earth’s upper mantle. The mineral transformations greatly hinder the movements of rock in the mantle. Subducting plates often have difficulty in breaking through […]
2.8 Trillion Tons of Nearly Fresh Water Found Under the Ocean
Next Big Future June 23, 2019 According to a team of researchers in the US (Columbia University, Woods Hole Oceanographic Institution) their data suggests continuous aquifers extending 90 km offshore New Jersey and Martha’s Vineyard, Massachusetts, on the U.S. Atlantic margin using new shallow water electromagnetic geophysical methods. The continuous submarine aquifer system spans at least 350 km of the U.S. Atlantic coast and contains about 2800 km3 (2.8 trillion tons) of low-salinity groundwater. The findings can be used to improve models of past glacial, eustatic, tectonic, and geomorphic processes on continental shelves and provide insight into shelf geochemistry, biogeochemical cycles, and the […]