Paleoseismology, which is the study of prehistoric or pre-instrumental earthquakes, is an interdisciplinary field of research mainly encompassing seismology, geology and geomorphology. Starting from identifying active faults, various field and laboratory techniques such as aerial photography interpretation, trench excavation, and radiocarbon dating are used to reveal the spatial extent and occurrence times of paleoearthquakes, and associated long-term movements of active faults. Evidence for paleoearthquakes is not only preserved in strata across a fault but also found far from the source as paleo-lique-faction, paleo-landslide, and paleo-tsunami deposits. Empirical relations between rupture length and slip versus earthquake magnitude from recent instrumentally recorded shocks enable us to estimate the size of future earthquakes on a fault or fault zone. Detailed rupture history of a fault also allows us to estimate time-dependent probabilistic seismic hazard. Although there are fundamental limitations and incompleteness in field data, contribution of paleoseismology in understanding the long-term faulting process is enormous and indispensable. Recent progress in paleoseismic data accumulations also allows seismologists and seismic engineers to make better seismic hazard maps to mitigate seismic damage in the future.
ASJC Scopus subject areas
- Earth and Planetary Sciences(all)