Hidden Subsurface Structures Scientists are wrapping up a major earthquake experiment in the Long Valley Caldera that will help to answer unresolved questions about the geologic structures and ongoing activity beneath the caldera and Mammoth Mountain on the southwest margin of the caldera. The 60 temporary seismic stations installed for the experiment is nearly triple the number of permanent seismic stations used to monitor the caldera for signs of volcano unrest. The resulting high-quality data is essential for advancing our understanding of the structure and processes at work deep beneath the surface. The instruments were installed beginning in May near Mammoth Mountain and in an area 4 to 6 kilometers southwest of the town of Mammoth Lakes and will be removed in late September.
Scientists anticipate having to spend many months analyzing all the earthquake data.
During the experiment so far, more than 1,600 earthquakes up to a magnitude 3.5 beneath the caldera were recorded by the permanent seismic network . The greater sensitivity of the temporary seismometers means that more than 100,000 earthquakes were recorded by the expanded network. Who The Mammoth 97 Experiment chiefly involves the efforts of scientists from the U.S. Geological Survey, Duke University, and the University of Durham, England. Also contributing are scientists and students from California Institute of Technology, Colorado School of Mines, Tulane University, and the University of Washington. This collaboration significantly improves our individual capabilities in recording and analyzing earthquakes beneath the caldera in many different ways.