Wednesday, October 19, 2016

USA, California: GRC Member Studies Ability of Geothermal Fluids to Move through Cracks and Pores

Underground Science: Berkeley Lab Digs Deep For Clean Energy Solutions (Berkeley Lab)

Berkeley Lab geologists Patrick Dobson (left) and Curt Oldenburg (right) along with Bill Roggenthen (center) of the South Dakota School of Mines and Technology at the kISMET site in the Sanford Underground Research Facility prior to drilling. (Photo courtesy Curt Oldenburg)
About a mile beneath the Earth’s surface in an old gold mine, Lawrence Berkeley National Laboratory (Berkeley Lab) scientists have built an observatory to study how rocks fracture. The knowledge they gain could ultimately help reduce greenhouse gas emissions and accelerate deployment of clean energy technologies.

The observatory is part of a Department of Energy (DOE) initiative that seeks to address challenges associated with the use of the subsurface for energy extraction and waste storage. Dubbed SubTER—or Subsurface Technology and Engineering Research, Development and Demonstration Crosscut—the initiative recognizes that the United States currently relies on the subsurface for more than 80 percent of its energy needs and that adaptive control of subsurface fractures and fluid flow is a crosscutting challenge that has the potential to transform energy production and waste storage strategies.

One key to gaining control is understanding how rocks fracture, in order to control it or prevent it, depending on the application. “We’re concerned with the ability of fluids to move through cracks and pores,” said Berkeley Lab geologist and GRC Member Patrick Dobson. “For some applications, such as engineered geothermal systems, you want fluids to move in order to mine the heat from the subsurface, so you want to create fractures. In others, such as carbon capture and sequestration, we’re more interested in making sure fractures don’t grow.”