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USGS Rock Physics Laboratrory.
David Lockner in the Rock Physics Laboratory at USGS in Menlo Park CA. He is setting up an acoustic emissions experiment which under controlled conditions records the failure process of a homogeneous rock under pressure. The rock is westerly granite which starts to crack under pressure until it fractures. The results of the fracture of rocks should be able to be recorded on an active fault but so far researchers have not been able to directly record this phenomenon because it usually happens 10km deep. It is believed that only about a 10 meter section of rock nucleates during an M6 earthquake such the one which occured at Parkfield in 2004. ( Peter Essick / Aurora Photos )
Size: 5120px × 3413px
Location: Meno Park California United States
Photo credit: © Peter Essick / Aurora Photos / Alamy / Afripics
License: Royalty Free
Model Released: No
Keywords: ca, earthquake, earthquakes, experiment, force, fracture, meno, park, physics, quake, quakes, rock, scientist, usa