This project will create a deep observatory for seismic activity.
SAFOD is designed to directly sample fault zone materials (rock and fluids), measure a wide variety of fault zone properties and monitor a creeping and seismically active fault zone at depth. A 2.5-mile-deep hole will be drilled through the San Andreas fault zone close to the hypocenter of the 1966 Parkfield earthquake, where the San Andreas fault slips through a combination of small-to-moderate magnitude earthquakes and aseismic creep. The drill site is located sufficiently far from the San Andreas fault (as determined by geologic observations, microearthquake locations and geophysical imaging) to allow for drilling and coring deviated holes through the fault zone starting at a vertical depth of about 2 miles and continuing through the fault zone until relatively undisturbed country rock is reached on the other side.