- Research Letter
- Open Access
A probabilistic approach to the seismic hazard in Kashmir basin, NW Himalaya
© The Author(s) 2019
- Received: 7 October 2018
- Accepted: 19 April 2019
- Published: 30 April 2019
Northwestern Himalaya is one of the most tectonically active domains of the Himalayan arc. The prevailing complex collisional tectonic setup is able to produce destructive earthquakes, most recent being the 8 October 2005 Kashmir earthquake (M7.6). In this study, the probabilistic seismic hazard assessment of the Kashmir basin of northwestern Himalaya is presented. The seismic hazard is assessed using point, areal and linear source models employing appropriate ground motion prediction equations to predict the expected ground motions. The seismic hazard maps are expressed in terms of g, seismic hazard curves at 2% and 10% probability of exceedance in 50 years and the design response spectra at 5% damping for four major towns of the basin at the engineering bedrock. The results are expressed as the hypocentral depth-wise hazard maps, predicted peak ground acceleration (PGA), pseudo-spectral acceleration (PSA) with 2% and 10% probability of exceedance within 50 years and the design response spectra with 5% damping of four major towns of Kashmir for engineering bedrock sites. The hypocentral depth-wise maps are shown in the ranges of 0–25 km, 25–70 km and > 70 km with 10% probability of exceedance in 50 years. The computation is based on smoothly gridded seismicity for each depth zone with a return period of 475 years. With the seismic source zones considered as sources, the seismic hazard maps show predicted peak ground acceleration (PGA) and pseudo-spectral acceleration (PSA) with 2% and 10% probability of exceedance within 50 years for engineering bedrock sites. The PSA maps are expressed in g at 0.2 and 1 s (s). From this preliminary study it is evident that overall Kashmir basin shows a very high seismic hazard, with southeastern part showing relatively higher hazard as compared to northwestern part. Among the major benchmark towns all show high predicted PGA, Anantnag shows the highest (0.65g). The present study thus advocates a significantly higher seismic hazard as compared to the BIS In: IS 1893–2002 (Part 1): Indian standard criteria for earthquake resistant design of structures, Part 1—general provisions and buildings, (2002).
- Seismic hazard
- Kashmir basin
- Probabilistic seismic hazard analysis
Seismic hazard refers to the probability of certain level of ground shaking in a given period of time. The effective ground motion is usually expressed as peak ground acceleration (g), and the assessment is either carried out by deterministic or probabilistic approach. In the deterministic method, a maximum credible earthquake likely to occur in the vicinity of the site of interest is estimated and the maximum credible level of ground motion is determined. While as in the probabilistic assessment, numerical probabilities are assigned to earthquake occurrences and their effects during a specific time period, such as the life of a given engineering structure (Yeats et al. 1997; Suckale et al. 2005). Usually earthquake catalogue is used as the primary probabilistic tool for projecting future events (Cornell 1968) but some seismic hazard assessment studies like Ward (1994) have used GPS data also. The basic foundations of the probabilistic seismic hazard assessment (PSHA) methodology were overlain by Cornell (1968) and McGuire (1976); since then there have been various modifications and developments in this basic framework. Cornell (1971) modified his earlier method (Cornell 1968) by introducing the concept of ground motion uncertainty, which is explained as the fact that ground motion could be different for two different earthquakes of the same magnitude occurring at the same distance. Zone free approach of Woo (1996) and Kramer’s (1996) incorporation of ground motion prediction equations (GMPE) with standard deviation in the probability calculation are also significant developments. Finally, uncertainties are taken into account in the framework by a weighted sum of various seismic source models, GMPEs and other seismicity parameters.
As per the national seismic hazard map of India (BIS 2002), Kashmir basin lies in Zone-V, which corresponds to the peak ground acceleration (PGA) of 0.4 g. As far as the seismic hazard assessment is concerned, the first-order deterministic seismic hazard assessment (DSHA) study of India was carried out by Parvez et al. (2003), wherein seismic hazard parameters were expressed in terms of design ground acceleration (g), peak ground velocity (cm/s) and peak ground displacement (cm). whereas the PSHA studies of India were conducted by Bhatia (1999) under Global Seismic Hazard Assessment Program (GSHAP) and recently by Nath and Thingbaijam (2012). In these studies, the hazard levels were presented as peak ground acceleration (PGA). But in order to assess the seismic hazard at regional level these studies conducted at much larger scale are not sufficient, so the results of these studies can be applied in the development of region-specific standard building code to design the earthquake resistant structures, land-use planning, hazard management, risk assessments and mitigation.
The Kashmir valley is a northwest-southeast directed tectonic basin in the northwestern Himalaya approximately ~ 140 km long and ~ 60 km wide. This intermountain Neogene-Quaternary basin is an important unit of the northwest Himalayan fold and thrust belt. The metamorphosed basement of this basin is overlain by thick fluvio-lacustrine (Cenozoic to Quaternary) sediments and surrounded by the peripheral Paleozoic and Mesozoic rocks (Kazmi and Jan 1977). The fluvio-lacustrine sediments are syn-orogenic and started depositing since last ~ 4 million years. These sediments are classified into Karewas and Riverine sediments, where the former are fluvio-lacustrine in origin and Plio-Pleistocene in age and later are riverine sediments of late Pleistocene–Holocene (Burbank and Johnson 1982, 1983; Burbank 1983; Bhatt 1989).
The Kashmir basin is surrounded by not only the main Himalayan boundary thrusts (Main Mantle Thrust, Main Central Thrust, Main Boundary Thrust and Panjal Thrust) Indus Tsangpo Suture Zone (ITSZ), Karakorum Fault (KF), Strike-slip Jhelum (JF), and Kishtwar Fault and the Hazara Thrust System (HTS), but also by active out-of-sequence fault, the Balakot–Bagh Fault (B–BF) and the stratigraphic equivalent of the B–BF, the Reasi Thrust (RT) as depicted in Fig. 1. The Main Mantle Thrust (MMT) is a main Himalayan thrust fault delineating the India–Eurasia plate boundary. The Main Boundary Thrust and Panjal Thrust loop around the Hazara–Kashmir Syntaxis (HKS) and run parallel along the southern margin of the Kashmir basin where former deforms the Precambrian rocks and the later deforms the formations of Oligocene–Miocene age, whereas the Main Central Thrust (MCT) is a 1.5 km-wide ductile shear zone which separates the higher Himalayan crystalline rocks from the lower Himalayan formations. Apart from main boundary thrusts there are two important thrust systems worth mentioning: the Reasi Thrust (RT) and the Hazara Thrust System (HTS). To the south of MBT Holocene activity is reported from the Reasi Thrust (RT), whereas HTS refers to the collection of three thrusts to the west of HKS (Stephenson et al. 2001; Sana and Nath 2016a, b). The Karakorum Fault (KF) is a dextral strike-slip fault trending almost parallel to the NW Himalayan range (Chevalier et al. 2005). The nearly E–W trending Indus Tsangpo Suture Zone (ITSZ) is the suture which formed as a result of India–Eurasia collision (Xu et al. 2015). There are also two important local strike-slip faults in the seismo-tectonic domain of the study region, the north–south trending Jhelum Fault (JF), and high angle NE-dipping Kishtwar Fault (Sana and Nath 2016b). The out-of-sequence faults like the northeast-dipping Bagh–Balakot Fault (B–BF) cannot be overlooked from the seismotectonic point of view as they are capable of generating disastrous earthquakes in the Kashmir Himalaya like the 8 October 2005 Kashmir earthquake (Avouac et al. 2006). The seismo-tectonic map in and around the Kashmir basin is shown as Fig. 1.
(1) The definition and delineation of sources of seismicity sources which in this case is zone free (hypocentral depth-wise seismicity smoothened earthquake catalogue), seismic source zones and faults. (2) The establishment of the recurrence of the earthquake activity from the sources, where each source is described by a recurrence relationship. (3) The third step involves the estimation of ground motion, which is usually expressed as peak ground acceleration (PGA). (4) Finally, the computation of seismic hazard is carried out and is expressed in terms of exceedance curves. The exceedance curves depict the probability of exceeding different levels of ground motion during a specified period of time in the area of interest (Reiter 1990).
Seismic sources and seismicity analysis
In this study, the zone free (seismicity smoothened hypocentral depth-wise earthquake catalogue) and areal (seismogenic zones) sources and faults are used to generate hazard curves and maps. Sana and Nath (2017) have developed an extensive uniform magnitude earthquake catalogue of the Kashmir Himalaya and surroundings using different sources. This earthquake catalogue is published as a supplement to Sana and Nath (2016a, b). It encompasses the period from 1885 to 2012. It is compiled from various sources likes Jones (1885), Ambraseys (2000), Ambraseys and Bilham (2003), Ambraseys and Douglas (2004), Szeliga et al. (2010), International Seismological Center (ISC), EHB (groomed version of ISC bulletin), United States Geological Survey (USGS), Indian Meteorological Division (IMD) and Pakistan Meteorological Division (PMD). Apart from giving detailed information about time (year, month, day, hour, minute and second) and location (latitude, longitude and depth), different magnitude types (Ms, mb and ML) reported in the sources have been converted into moment magnitude (Mw). This earthquake catalogue is used as an input for source zone free layer-wise probabilistic hazard analysis. Layer-wise seismicity smoothening was applied to the epicenters of this earthquake catalogue to determine the activity rates for each magnitude interval using the approach of Woo (1996). Owing to the seismo-tectonic complexity of the NW Himalaya, the catalogue was divided into shallow (0–25 km), intermediate (25–70 km) and deep to very deep (> 70 km) hypocentral depth. These depth-range wise smoothened catalogues were used as zone free point sources for the depth-wise probabilistic seismic hazard analysis of the Kashmir basin.
Showing seismicity analysis results of all the seismic sources zones considered for PSHA of Kashmir basin
6.11 ± 0.57
0.81 ± 0.05
3.9 ± 0.05
8.1 ± 0.36
5.71 ± 0.20
0.79 ± 0.01
3.9 ± 0.17
7.3 ± 0.58
5.95 ± 0.15
0.84 ± 0.19
4.3 ± 0.35
7.1 ± 0.58
7.86 ± 0.26
1.32 ± 0.1
4.4 ± 0.01
6.8 ± 0.58
8.12 ± 0.38
1.29 ± 0.03
4.7 ± 0.17
6.8 ± 0.58
Showing seismicity parameters, magnitude of completeness (Mc) and mmax of all the major faults in and around the Kashmir basin from Sana and Nath (2017)
Starting year of catalogue
a-value (entire time period)
mmax (± 0.28)
0.70 ± 0.04
3.8 ± 0.03
1.43 ± 1.17
4.5 ± 0.44
1.09 ± 0.53
4.1 ± 0.23
0.80 ± 0.14
4.0 ± 0.24
1.10 ± 0.98
3.9 ± 0.37
0.50 ± 0.07
3.3 ± 0.28
0.50 ± 0.07
3.3 ± 0.28
1.15 ± 0.13
4.5 ± 0.11
1.01 ± 0.15
3.5 ± 0.42
0.53 ± 0.03
3.0 ± 0.11
Ground motion prediction equations
Site conditions play an important role in seismic hazard assessment. For seismic hazard assessment at a site, usually NEHRP (National Earthquake Hazards Reduction Program) site classification is used, which is based on average shear wave velocity (m/s) for the 30 m-deep soil column from the surface (BSSC 2001). For regional hazard computations in Indian context, Nath and Thingbaijam (2012) propose firm-rock conditions (standard engineering bedrock) to be more realistic for hazard evaluation. So, in this study, we consider standard engineering bedrock for hazard computations, which corresponds to Vs of 760 m/s and is defined as the boundary between site class B and C of NEHRP classification.
Predicted peak ground acceleration (PGA) in g of major towns in Kashmir basin with 10% probability of exceedance in 50 years
This study presents probabilistic seismic hazard analysis of the Kashmir basin, NW Himalaya based on the Sana and Nath (2017) earthquake catalogue. The contribution from zone free seismicity, seismic source zones and faults are considered from different perspectives using appropriate ground motion prediction equations and the hazard is computed at different probabilities of exceedance. The present study advocates a significantly higher seismic hazard as compared to the BIS (2002). This study also recommends active fault and paleoseismic studies in the region, the outputs of which will not only refine the seismic hazard assessment models but also make them more realistic. As for example in this study and all the seismicity based seismic hazard models, the contribution from every fault in and around the region is given equal weightage, whereas in reality, the active faults are the actual contributors to the seismic hazard.
All the analysis, figure plotting and write up of the manuscript were done by the author. The author read and approved the final manuscript.
I’m grateful to Sankar K. Nath for reading the first draft of this manuscript, Scott Callaghan (University of Southern California, California) for his insightful comments and Arbind K. Yadav for his generous help in coding of the PSHA model for the Kashmir basin. I’m also grateful to the two anonymous reviewers, their comments helped greatly in the improvement of the quality of this manuscript.
The author declares that he has no competing interests.
Availability of data and materials
All the data used in this paper came from the published and unpublished sources listed in the references.
I am thankful to University Grants Commission, India for CSIR-UGC (JRF) NET Fellowship and Institute of Rock Structure and Mechanics, CAS for Long Term Conceptual Development Research Organization for the grant (Grant No: RVO:67985891).
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- Ahmad B, Sana H, Alam A (2014) Macroseismic intensity assessment of 1885 Baramulla earthquake of northwestern Kashmir Himalaya, using the Environmental Seismic Intensity scale (ESI 2007). Quatern Int 321:59–64View ArticleGoogle Scholar
- Aki K (1965) Maximum likelihood estimate of b in the formula log N = a – bM and its confidence limits. Bull Earthq Res Inst 43:237–239Google Scholar
- Ambraseys N (2000) Reappraisal of north-Indian earthquakes at the turn of the 20th century. Curr Sci 79:101–114Google Scholar
- Ambraseys N, Bilham R (2003) Earthquakes in Afghanistan. Seismol Res Lett 74:107–123View ArticleGoogle Scholar
- Ambraseys N, Douglas J (2004) Magnitude calibration of north Indian earthquakes. Geophys J Int 159:165–206View ArticleGoogle Scholar
- Avouac JP, Ayoub F, Leprince S, Konca O, Helmberger DV (2006) The 2005, M w 7.6 Kashmir Earthquake: sub-Pixel correlation of ASTER images and seismic wave form analysis. Earth Planet Sci Lett 249:514–528View ArticleGoogle Scholar
- Bender B (1983) Maximum likelihood estimation of b-values for magnitude grouped data. Bull Seismol Soc Am 73:831–851Google Scholar
- Bhatia SC, Kumar MR, Gupta HK (1999) A probabilistic seismic hazard map of India and adjoining regions. Ann Geophys 42(6):153–166Google Scholar
- Bhatt DK (1989) Lithostratigraphy of Karewa group, Kashmir valley, India and a critical review of its fossil record. Memoirs Geol Surv India 122:3–9Google Scholar
- BIS (2002) IS 1893–2002 (Part 1): Indian standard criteria for earthquake resistant design of structures. Part 1—general provisions and buildings. Bureau of Indian Standards, New DelhiGoogle Scholar
- Boore DM, Atkinson GM (2008) Ground-motion prediction equations for the average horizontal component of PGA, PGV, and 5%-damped PSA at spectral periods between 0.01 s and 10.0 s. Earthquake Spectra 24:99–138View ArticleGoogle Scholar
- BSSC (Building Seismic Safety Council) (2001) NEHRP Recommended provisions for seismic regulations for new buildings and other structures. 2000 ed. Part 1: Provisions, Building Seismic Safety Council for the Federal Emergency Management Agency (Report FEMA 368), Washington, DCGoogle Scholar
- Burbank DW (1983) The chronology of Intermontane-basin development in the northwestern Himalaya and the evolution of the Northwest Syntaxis. Earth Planet Sci Lett 64:77–92View ArticleGoogle Scholar
- Burbank DW, Johnson GD (1982) Intermontane-basin development in the past 4 My in the north-west Himalaya. Nature 298:432–436View ArticleGoogle Scholar
- Burbank DW, Johnson GD (1983) The Late Cenozoic chronologic and stratigraphic development of the Kashmir Intermontane basin, northwestern Himalaya. Paleogeogr Paleoclimatol Paleoecol 43:205–235View ArticleGoogle Scholar
- Campbell KW, Bozorgnia Y (2008) NGA ground motion model for the geometric mean horizontal component of PGA, PGV, PGD and 5% damped linear elastic response spectra for periods ranging from 0.01 to 10s. Earthquake Spectra 24:139–171View ArticleGoogle Scholar
- Chevalier M-L, Ryerson FJ, Tapponnier P, Finkel RC, vander Woerd J, Haibing L, Qing L (2005) Slip-rate measurements on the Karakorum Fault may imply secular variations in fault motion. Science 307(5708):411–414. https://doi.org/10.1126/science.1105466 View ArticleGoogle Scholar
- Christenson GE (1994) Ground Shaking in Utah. Utah Geol Surv Public Inf Series 29:1–4Google Scholar
- Cornell CA (1968) Engineering seismic risk analysis. Bull Seismol Soc Am 58:1583–1606Google Scholar
- Cornell CA (1971) Probabilistic analysis of damage to structures under seismic loads. In: Howells DA, Haigh IP, Taylor C, editors. Dynamic waves in civil engineering. Proceedings of a conference organized by the Society for earthquake and civil engineering dynamics, Wiley, New York, pp 473–493Google Scholar
- Dasgupta S, Pande P, Ganguly D, Iqbal Z, Sanyal K, Venaktraman NV, Dasgupta S, Sural B, Harendranath L, Mazumdar K, Sanyal S, Roy A, Das LK, Misra PS, Gupta H (2000) Seismotectonic atlas of India and its environs. Geol Surv India Spec Publ 59:87Google Scholar
- Douglas J (2003) Earthquake ground motion estimation using strong-motion records: a review of equations for the estimation of peak ground acceleration and response spectral ordinates. Earth Sci Rev 61(1–2):43–104View ArticleGoogle Scholar
- Guttenberg R, Richter CF (1944) Frequency of earthquakes in California. Bull Seism Soc Am 34:185–188Google Scholar
- Hayes GP, Myers EK, Dewey JW, Briggs RW, Earle PS, Benz HM, Smoczyk GM, Flamme HE, Barnhart WD, Gold RD, Furlong KP (2017) Tectonic summaries of magnitude 7 and greater earthquakes from 2000 to 2015: U.S. Geological Survey Open-File Report, vol. 2016–1192, p. 148. https://doi.org/10.3133/ofr20161192
- Jones EA (1885) Report on the Kashmir earthquake of 30th May 1885. Rec Geol Surv India XVIII(4):221–227Google Scholar
- Kazmi AH, Jan MQ (1977) Geology and Tectonics of Pakistan. Graphic Publishers, Karachi, p 545Google Scholar
- Kijko A (2004) Estimation of the maximum earthquake magnitude Mmax. Pure Appl Geophys 161:1–27View ArticleGoogle Scholar
- Kramer SL (1996) Geotechnical earthquake engineering. Pearson Education Pvt. Ltd., LondonGoogle Scholar
- McGuire RK (1976) FORTRAN computer program for seismic risk analysis, US Geological Survey, Open file report. vol. 76–67Google Scholar
- Mueller C, Briggs R, Wesson R, Petersen M (2015) Updating the USGS seismic hazard maps for Alaska. Quatern Sci Rev 113:39–47. https://doi.org/10.1016/j.quascirev.2014.10.006 View ArticleGoogle Scholar
- Nath SK, Thingbaijam KKS (2011) Peak ground motion predictions in India: an appraisal for rock sites. J Seismol 15:295–315View ArticleGoogle Scholar
- Nath SK, Thingbaijam K (2012) Probabilistic seismic hazard assessment of India. Seismol Res Lett 83(1):135–149View ArticleGoogle Scholar
- NCSDP (2011) Guidelines for Preparation and submission of site-specific seismic study report of river valley project to National Committee on Seismic Design Parameters (NCSDP). Central Water Commission, Government of India, New DelhiGoogle Scholar
- Parvez IA, Vaccari F, Panza GF (2003) A deterministic seismic hazard map of India and adjacent areas. Geophys J Int 155:489–508. https://doi.org/10.1046/j.1365-246X.2003.02052.x View ArticleGoogle Scholar
- Reiter L (1990) Earthquake Hazard Analysis-Issues and insights. Columbia University Press, New York, p 254Google Scholar
- Sana H, Nath SK (2016a) Liquefaction potential analysis of the Kashmir valley alluvium, NW Himalaya. Soil Dyn Earthquake Eng 85:11–18View ArticleGoogle Scholar
- Sana H, Nath SK (2016b) In and Around the Hazara-Kashmir Syntaxis: a seismotectonic and seismic hazard perspective. J Indian Geophys Union 20(05):496–505Google Scholar
- Sana H, Nath SK (2017) Seismic source zoning and maximum credible earthquake prognosis of the Greater Kashmir Territory, NW Himalaya. J Seismol 21(2):411–424View ArticleGoogle Scholar
- Sharma ML, Douglas J, Bungum H, Kotadia J (2009) Ground motion prediction equations based on data from the Himalayan and Zagros regions. J Earthquake Eng 13:1191–1210View ArticleGoogle Scholar
- Sitharam TG, Kolathayar S, James N (2014) Probabilistic assessment of surface level seismic hazard in India using topographic gradient as a proxy for site condition. Geosci Front 1:1. https://doi.org/10.1016/j.gsf.2014.06.002 View ArticleGoogle Scholar
- Stephenson BJ, Searle MP, Waters DJ, Rex DC (2001) Structure of the Main Central Thrust zone and extrusion of the High Himalayan deep crustal wedge, Kishtwar–Zanskar Himalaya. J Geol Soc 158:637–652View ArticleGoogle Scholar
- Suckale J, Grünthal G, Regnier M, Bosse C (2005) Probabilistic seismic hazard assessment for Vanuatu. http://webdoc.sub.gwdg.de/ebook/serien/tm-v/STR/0516.pdf
- Szeliga W, Hough S, Martin S, Bilham R (2010) Intensity, magnitude, location, and attenuation in India for felt earthquakes since 1762. Bull Seismol Soc Am 100(2):570–584View ArticleGoogle Scholar
- Utsu T (1999) Representation and analysis of the earthquake size distribution: a historical review and some new approaches. Pure Appl Geophys 155:509–535View ArticleGoogle Scholar
- Ward SN (1994) A multidisciplinary approach to seismic hazard in southern California. Bull Seismol Soc Am 84:1293–1309Google Scholar
- Wells DL, Coppersmith KJ (1994) New empirical relationships among magnitude, rupture length, rupture width, rupture area, and surface displacement. Bull Seismol Soc Am 84(4):974–1002Google Scholar
- Wiemer S (2001) A software package to analyze seismicity: ZMAP. Seismol Res Lett 72(3):373–382View ArticleGoogle Scholar
- Woo G (1996) Kernel estimation methods for seismic hazard area source modeling. Bull Seismol Soc Am 86(2):353–362Google Scholar
- Xu Z-Q, Dilek Y, Yang J-S, Liang F-H, Liu F, Ba D-Z, Cai Z-H, Li G-W, Dong H-W, Ji S-C (2015) Crustal structure of the Indus-Tsangpo suture zone and its ophiolites in southern Tibet. Gondwana Res 27(2):507–524View ArticleGoogle Scholar
- Yeats RS, Sieh K, Allen CR (1997) The geology of earthquakes. Oxford University Press, Oxford, p 450Google Scholar