Contents lists available at ScienceDirect Tectonophysics journal homepage: www.elsevier.com/locate/tecto Spatial distribution of earthquake potential along the Himalayan arc Yogendra Sharma a, ⁎ , Sumanta Pasari a , Kuo-En Ching b , Onkar Dikshit c , Teruyuki Kato d,e , Javed N. Malik f , Chung-Pai Chang g , Jiun-Yee Yen h a Department of Mathematics, Birla Institute of Technology and Science, Pilani, India b Department of Geomatics, National Cheng Kung University, Taiwan c Department of Civil Engineering, Indian Institute of Technology Kanpur, India d Earlier at Earthquake Research Institute, The University of Tokyo, Japan e Presently at Hot Spring Research Institute of Kanagawa Prefecture, Japan f Department of Earth Sciences, Indian Institute of Technology Kanpur, India g Center for Space and Remote Sensing Research, National Central University, Taiwan h Department of Natural Resources and Environmental Studies, National Dong Hwa University, Taiwan ARTICLE INFO Keywords: Himalaya Earthquake potential GPS velocity Geodetic strain rate Moment deficit rate ABSTRACT To determine the spatial distribution of earthquake potential along the active Himalayan arc, we utilize GPS measurements and earthquake data. We derive horizontal velocity field and 2-D strain rates from a new set of 41 regional GPS stations along with 446 published velocities. We convert these strain rate tensors to geodetic moment rate build-up within 24 contiguous segments and compare to the seismic moment rate release derived from a reassessed earthquake catalog of 900 years. The geodetic to seismic moment rate ratio, an indicator of stored strain energy, varies from below unity to more than 50 in different segments. The estimated geodetic moment rate ranges from 1.7 × 10 18 Nm/yr to 10.2 × 10 18 Nm/yr, whereas the seismic moment rate ranges from 3.7 × 10 16 Nm/yr to 5.1 × 10 19 Nm/yr. This variation between the geodetic and seismic moment rate corresponds to a moment deficit rate of ~1.15×10 17 Nm/yr to 7.97 × 10 18 Nm/yr along various segments of the study region. The above moment deficit rate provides an equivalent earthquake potential of magnitude 5.7 - 8.2 in different segments. Specifically, the higher earthquake potential (M w ≥8.0) corresponds to the segments in the central seismic gap and the northeast part of Himalaya, whereas the lower earthquake potential (M w < 7.0) corresponds to the segments encompassing the rupture areas of recent large events. The present findings not only provide input constraints on the contemporary crustal deformation but also contributes to the time-dependent seismic hazard analysis along the Himalaya. 1. Introduction The region of highest seismic activity in south-central Asia is the Himalaya, where several large earthquakes in the past have resulted in tens of thousands of casualties. An M w > 8 earthquake has also been claimed to be overdue in the Himalayan orogen (Bilham and Ambraseys, 2005; Gupta and Gahalaut, 2015; Stevens and Avouac, 2016; Bilham, 2019). However, the estimated moment deficit, possible maximum magnitude and prospective location of future earthquakes certainly vary along the Himalayan arc (Bilham, 2019; Pasari, 2018; Bilham et al., 2001; Srivastava et al., 2015; Stevens and Avouac, 2015; Ader et al., 2012; Bungum et al., 2017; Pasari and Dikshit, 2014; Pasari, 2019a; Bhatia et al., 2018). Therefore, with a high-resolution geodetic data and an updated earthquake catalog, re-evaluation of the spatial distribution of earthquake is essential to assess the contemporary seismic hazard along the Himalayan collision zone (Riguzzi et al., 2012; Pasari and Dikshit, 2015; Pasari and Mehta, 2018; Pasari and Sharma, 2020). Two major components to assess the energy budget of a seismogenic area are the geodetic strain build-up rate and the stress release rate through earthquakes. Consequently, the comparison between the geo- detic and seismic moment rates can be interpreted as a significant in- dicator of seismic hazard along the Himalaya (Riguzzi et al., 2012; Pancha et al., 2006; Allmendinger et al., 2007; Middleton et al., 2018). Ader et al. (2012) estimated that the moment deficit rate along the locked Main Himalayan Thrust (MHT) is 6.6 ± 0.4×10 19 Nm/yr be- neath the Nepal Himalaya. Similarly, Lindsey et al. (2018) computed the total moment rate within Nepal over a 1000 km length of the MHT https://doi.org/10.1016/j.tecto.2020.228556 Received 6 March 2020; Received in revised form 3 July 2020; Accepted 4 July 2020 ⁎ Corresponding author at: Department of Mathematics, Birla Institue of Technology and Science, Pilani, Rajasthan 333031, India. E-mail addresses: yogenmaths2738@gmail.com, p2016413@pilani.bits-pilani.ac.in (Y. Sharma). Tectonophysics 791 (2020) 228556 Available online 12 July 2020 0040-1951/ © 2020 Elsevier B.V. All rights reserved. T