by US Geological Survey, August 8, 2019 in ScienceDaily
Scientists have taken the temperature of a huge expanse of seafloor in the Arctic Ocean in new research by the U.S. Geological Survey and the Geological Survey of Canada. The study, published in the Journal of Geophysical Research, is accompanied by the release of a large marine heat flow dataset collected by the USGS from an ice island drifting in the Arctic Ocean between 1963 and 1973. These never-before-published data greatly expand the number of marine heat flow measurements in the high Arctic Ocean.
Marine heat flow data use temperatures in near-seafloor sediments as an indication of how hot Earth’s outer layer is. These data can be used to test plate tectonic theories, provide information on oil and gas reservoirs, determine the structure of rock layers and infer fluid circulation patterns through fractures in those rock layers.
by K. Richard, July 5, 2019 in NoTricksZone
Geothermal heat flux can foment upper mantle temperature anomalies of 800–1000 °C, and these extreme heat intensities have been found to stretch across 500 km of central-east Greenland. This could result in “a significant contribution of ice melt to the ice-drainage system of Greenland” (Artemieva et al., 2019).
Evidence of more than 100,000 formerly or currently active volcanic vents permeate the Earth’s sea floor (Kelley, 2017).
Active volcanoes spew 380°C sulfuric acid and “metal-laden acidic fluids” into the bottom waters of the world ocean on a daily basis. In other words, literal ocean acidification is a natural phenomenon.
The carbon dioxide concentrations present in these acidic floods reach “astounding” levels, dwarfing the potential for us to even begin to appreciate the impact this explosive geothermal activity has on the Earth’s carbon cycle (Kelley, 2017).
La géologie, une science plus que passionnante … et diverse