Application of chirp technology in earth science: From sediment dispersal to acoustic trenching of faults

Abstract

CHIRP technology developed and perfected by Steve Schock and others allows scientists to image the earth at the scale processes shape it. Here, we present CHIRP images from a number of different tectonic and depositional settings. One example is from the Salton Sea, where we discovered faults near the southern end of the San Andreas Fault. Rupture on these newly discovered step-over faults has the potential to trigger large earthquakes on the southern San Andreas Fault (M7.5). Using the CHIRP technology to conduct “acoustic trenching” has revolutionized the study of paleoseismology and geohazards. Another example of CHIRP technology is from the continental shelf edge, offshore the US East Coast where large tensional cracks are observed (~4 km long and 1 km wide) and they might mark the location of the next slope failure along the margin. Even though rare, slope failure along the continental margin may lead to tsunami generation along the US East Coast. Sedimentary layers are the recorder of earth history and CHIRP technology allows us to image and decipher the origin of these layers in terms of climate change and tectonic deformation. The development of this technology is clearly one of the big advancements in subsurface geophysical imaging.