Paleo-earthquake signatures from the South Wagad Fault (SWF), Wagad Island, Kachchh, Gujarat, western India: A potential seismic hazard Javed N. Malik a, * , Mahendrasinh S. Gadhavi b , Girish Ch Kothyari c , Sravanthi Satuluri d a Department of Earth Sciences, Indian Institute of Technology Kanpur, Kanpur, 208016, India b Civil Engineering Department, L. D. College of Engineering, Ahmedabad, Gujarat, India c Institute of Seismological Research, Raisan, Gandhinagar, Gujarat, India d Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India article info Article history: Received 17 May 2016 Received in revised form 10 December 2016 Accepted 23 December 2016 Available online 27 December 2016 Keywords: Active faults Paleoseismology South Wagad Fault Seismic hazard Kachchh Gujarat abstract In last 500 years, Kachchh experienced several large magnitude earthquakes (6.0  M  7.8), however, not all accompanied surface rupture. The 1819 Allah Bund earthquake (Mw7.8) accompanied surface rupture, whereas, the 2001 Bhuj event (Mw7.6) occurred at a depth of 23 km on E-W striking south dipping thrust fault remained blind. Discontinuities between the denser-brittle basement (?) and overlying ductile-softer Mesozoic-Tertiary-Quaternary succession resulted in a different geometry of faulting. Normal faults associated with rift were reactivated as reverse faults during inversion tectonics, propagated in sedimentary succession and arrested. Thrust-ramps developed along the discontinuities accompanied surface ruptures. Folded structures along the South Wagad Fault (SWF) e an active thrust, exhibits lateral-propagation of fold segments and linkage, suggestive of fault-related-fold growth. Paleoseismic investigations revealed evidence of at least three paleo-earthquakes. Event I occurred before BCE 5080; Event II between BCE 4820 and 2320, and was probably responsible for a massive damage at Dholavira e Harappan site. Event III was between BCE 1230 and 04, most likely caused severe damage to Dholavira. Archaeo-seismological Quality Factor (AQF) of 0.5 suggests that the Dholavira is vulnerable to earthquakes from nearby active faults. With 1500e2000 yr of recurrence interval, occur- rence of a large magnitude earthquake on SWF cannot be ruled out. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction The Kachchh in the Stable Continental Region (SCR) of western India is located about 500 km southeast of the seismically most active plate boundaries along Chaman Fault System and Makran Subduction Zone. The diversified landscape and rich ancient culture of Kachchh has not only attracted the historians, but also the geo- morphologists and geologists to understand the landscape changes that took place in last 10,000 years (Merh, 1995; Malik et al., 1999). Though, away from the plate boundary, Kachchh experienced several moderate to large magnitude (6.0  M  7.8) damaging earthquakes during the recent historic past. These earthquakes are 1668 Indus-Delta (M7), 1819 Allah Bund (Mw7.8), 1956 Anjar (Mw6.0) (e.g., Johnston and Kanter, 1990; Chung and Gao, 1995; Malik et al., 2001a; Bilham et al., 2007). The recent 2001 Bhuj earthquake (Mw7.6) was the most destructive event. This earth- quake has raised several concerns related to the Seismic Hazard Assessment (SHA) of Kachchh and its neighboring areas. Usually, major earthquake in SCR can result into a widespread damage, because the attenuation of seismic energy in plate interiors from such earthquake is relatively low (Hanks and Johnston, 1992; Crone et al., 2003). Therefore, even moderate magnitude event as expe- rienced in the case of 1993 Killar-Latur earthquake (Mw 6.2) may be extremely damaging. Historical data and paleoseismic studies from the Great Rann of Kachchh revealed evidence of large magnitude earthquakes those occurred during a time span of BCE 800e1000 (Rajendran and Rajendran, 2001; Rajendran et al., 2008). Also, active fault studies from Kachchh Mainland revealed that the major faults, viz. the * Corresponding author. E-mail addresses: javed@iitk.ac.in (J.N. Malik), mahendrasinh@gmail.com (M.S. Gadhavi), kothyarigirish_k@rediffmail.com (G.C. Kothyari), sravisri@iitk.ac.in (S. Satuluri). Contents lists available at ScienceDirect Journal of Structural Geology journal homepage: www.elsevier.com/locate/jsg http://dx.doi.org/10.1016/j.jsg.2016.12.011 0191-8141/© 2016 Elsevier Ltd. All rights reserved. Journal of Structural Geology 95 (2017) 142e159