August 07, 2024
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Hydrogen is the most abundant element in the universe and its distribution, transfer, and speciation in the deep Earth remain a fascinating topic of ongoing research. We review the most notable discoveries constraining the H cycle in the deep Earth. This includes new methods for detecting hydrogen, insights into the size of deep reservoirs, and new constraints from inclusions in ultradeep diamonds. Advances in seismic and magneto- telluric imaging provide unique data on the storage and mobility of water in Earth´s interior. Models of the early Earth and of its habitability critically depend on the behavior of hydrogen in a magma ocean–atmosphere system. Later in Earth history, water may have been essential for establishing plate tectonics, a phenomenon making Earth a unique planet.
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