by M. Van Wyk De Vries et al., August 16, 2018 in Geol.Soc.London
Abstract: The West Antarctic Ice Sheet overlies the West Antarctic Rift System about which, due to the comprehensive ice cover, we have only limited and sporadic knowledge of volcanic activity and its extent. Improving our understanding of subglacial volcanic activity across the province is important both for helping to constrain how volcanism and rifting may have influenced ice-sheet growth and decay over previous glacial cycles, and in light of concerns over whether enhanced geo- thermal heat fluxes and subglacial melting may contribute to instability of the West Antarctic Ice Sheet. Here, we use ice-sheet bed-elevation data to locate individual conical edifices protruding upwards into the ice across West Antarctica, and we propose that these edifices represent subglacial volcanoes. We used aeromagnetic, aerogravity, satellite imagery and databases of confirmed volca- noes to support this interpretation. The overall result presented here constitutes a first inventory of West Antarctica’s subglacial volcanism. We identified 138 volcanoes, 91 of which have not previously been identified, and which are widely distributed throughout the deep basins of West Antartica, but are especially concentrated and orientated along the >3000 km central axis of the West Antarctic Rift System.
by A.J. Kondash et al., August 15, 2018 in ScienceAdvances
Unconventional oil and gas exploration in the United States has experienced a period of rapid growth, followed by several years of limited production due to falling and low natural gas and oil prices. Throughout this transition, the water use for hydraulic fracturing and wastewater production in major shale gas and oil production regions has increased; from 2011 to 2016, the water use per well increased up to 770%, while flowback and produced water volumes generated within the first year of production increased up to 1440%. The water-use intensity (that is, normalized to the energy production) increased ubiquitously in all U.S. shale basins during this transition period. The steady increase of the water footprint of hydraulic fracturing with time implies that future unconventional oil and gas operations will require larger volumes of water for hydraulic fracturing, which will result in larger produced oil and gas wastewater volumes.
by Javier, June 28, 2018
A conservative outlook on 21st century climate change
Summary: For the past decade anthropogenic emissions have slowed down, and continuation of current trends suggests a peak in emissions by 2050. Atmospheric CO2levels should reach 500 ppm but might stabilize soon afterwards, as sinks increase their CO2uptake. Solar activity is expected to continue increasing after the present minimum, as the millennial cycle works its way towards a late 21st century peak. The reduction in the rate of warming might continue until ~ 2035 followed by renewed warming, and temperature stabilization at about +1.5°C above pre-industrial. The pause in summer Arctic sea ice melting might also continue until ~ 2035. Renewed melting is probable afterwards, but it is unlikely that Arctic summers will become consistently ice free even by 2100.
by A. Bojanowski, August 4, 2018 in NoTricksZone/Der Spiegel
Geology major, science journalist Axel Bojanowski just penned a commentary at Spiegel Online on the recent hot weather hype we witnessed in the wake of Europe’s warm and unusually dry summer.
The title of his commentary: “Overheated – Forest Fires, Drought, Heat – Has The Climate Catastrophe Already Arrived? Time For A Cool Examination.”
See also here
La géologie, une science plus que passionnante … et diverse