Earthquake Geology:A tool for Seismic Hazard Assessment

Before 1970, the assessment of earthquake hazard in United States and the USSR was based solely on the historic earthquake record. But now most workers investigate seismically active faults to undertake paleoseismic studies in both regional and site-specific seismic hazard. In most of the seismically active regions of the world (including Himalayan belt) many active fault zones have no historic record for large magnitude earthquakes. Paleoseismic study is a common practice in many countries like United States, Japan, New Zealand etc. These studies have provided significant data towards recognition of individual paleoseismic (old earthquake) events, behavior of individual active fault segment, rate of faulting; reconstructing the history of large magnitude earthquakes and their repeat time etc. Paleoseismological studies are very important because they provide valuable information to the society to assess the probability and severity for the future earthquakes. This is an upcoming field in India. This course is designed for the PG as well as UG students to help them in developing their knowledge in this field.

INTENDED AUDIENCE :UG/PG students of Science and Engineering.
PREREQUISITES : Nil
INDUSTRY SUPPORT : Nil

COURSE LAYOUT Week 1 : Crustal deformation and earthquakes (Seismicity), and its significance Plate Tectonics Week 2 : Signature of prehistoric earthquakes: Primary and Secondary signatures preserved in landforms and sediment succession Week 3 : Signature of prehistoric earthquakes (continued): Primary and Secondary signatures preserved in landforms and sediment succession Week 4 : Interpretation and Identification of Active Fault and associated Tectonic Landforms: Photogeologic Mapping, on-fault and off-fault landforms, identification and mapping of active faults and associated landforms. Week 5 : Interpretation and Identification of Active Fault and associated Tectonic Landforms (continued): Identification and mapping of active faults and associated landforms in different tectonic environments. Structural analysis of active faults & its implication to regional scale tectonics Week 6 : Field Techniques in Paleoseismology: Quantification of active fault scarp by precise mapping, identification of old (prehistoric) earthquake by trenching, mapping of deformed sedimentary succession by faulting. Week 7 : Field Techniques in Paleoseismology (continued): Estimation of net displacement during single event, slip rate, magnitude of historic earthquake, recurrence interval, and prediction of future earthquake if possible Week 8 : Identification and mapping of secondary effects: Secondary effects due to strong seismic shaking – identification of paleo-liquefaction features Dating Techniques: OSL and C14 Week 9 : Paleo-tsunami geology: Identification of Paleo-tsunami and Mega-subduction zone earthquakes signatures in the coastal region along subduction zones Week 10 : Paleo-tsunami geology (continued): Understanding land-level change caused by major earthquakes. Decoupling the role of climate and tectonics Week 11 : Paleo-tsunami geology (continued): Understanding the effect of near-field and far-field earthquakes from stratigraphic records. Effects of near-field and far-field tsunami Week 12 : Field Study: Identification and mapping of active faults and associated landforms in field.