Advanced Microseismic Analysis for Enhanced Geothermal Energy
One method of interrogating the subsurface is to use microseismic events to map underground structures, fracture networks, and fluid pathways. In a three-year project funded by GTP through the American Recovery and Reinvestment Act, a Livermore team is developing advanced microseismic analysis techniques to understand what happens beneath Earth’s surface. The team is developing a sophisticated computer algorithm to better extract information from seismic data and ultimately promote the development of cost-effective enhanced geothermal systems (EGSs) that can draw energy from the subsurface and convert it for electric generation.
Traditionally, power plants produce geothermal energy only in high-temperature locations where naturally occurring interconnected cracks are filled with hot water or steam. However, much more geothermal energy is located in dry or impermeable rock, where water or a network of cracks may not be present. The temperature of Earth at a depth of 3 to 10 kilometers is highly variable but can exceed 300°C. EGS technology can be used to enhance existing fractures or create new ones and introduce water into these hot subsurfaces, thereby expanding the number of viable geothermal sites. Once an underground reservoir of water-filled cracks is created, power plants at the surface can either directly produce steam or use the geothermally heated water to create steam, which then turns the turbines that power generators.
For more details, see the Science and Technology Review article Seismic Data Pinpoint Fractures for Geothermal Energy.
