GPS derived crustal deformation analysis of Kachchh, zone of 2001(M7.7) earthquake, Western India

Quaternary International 507 (2019) 295–301

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GPS derived crustal deformation analysis of Kachchh, zone of 2001(M7.7) earthquake, Western India

T

Rakesh K. Dumka∗, S. Chopra, Sandip Prajapati Institute of Seismological Research, Gandhinagar, Gujarat, 382009, India

A R T I C LE I N FO

A B S T R A C T

Keywords: GPS Deformation Intra plate Strain rate Kachchh Indian plate

In this study, we present the first estimates of crustal deformation using the time series (2009–2015) from GPS Network of Gujarat (GNG), comprising 10 GPS continuous and 5 campaign mode stations in the seismically active Kachchh region. The GPS data were processed using GAMIT/GLOBK/GLORG software and results reveal very low amount of intra-plate deformation in this part of the Indian plate. International Terrestrial Reference Frame (ITRF) velocity of sites deduced in this study indicates 46–51 mm/yr of motion with one sigma uncertainty. A maximum of ≈3.0 ± 0.5 mm/yr of deformation has been estimated in the Kachchh region. However, estimated strain rate from the velocity field indicates a maximum strain of 5 nano-strain/yr. Our results indicate deformation of a weak zone, where earthquakes may trigger due to the combination of local as well as regional stress. The analysis of strain tensors near the major fault systems (KMF, KHF, SWF and GF) indicates strike normal compression in the area. The low rate of deformation, derived in the present study, is important to understand the seismic hazard level in this part of the Indian intra-Plate.

1. Introduction The western margin of the Indian plate is a triple junction of three failed rifts, namely, Kachchh, Cambay and Narmada (Biswas, 1987) (Fig. 1). These rifts were formed during the northward movement of the Indian plate after the breakup from Gondwanaland between late Triassic to late Cretaceous (Biswas, 1987). The rifting was interrupted at the beginning of the collision of the Indian plate with Eurasian plate in the Late Cretaceous (Molnar and Tapponnier, 1975). Post-collision, the Kachchh and Narmada rifts became zones of compression and primordial faults get reactivated thus became the strained regions and responsible for earthquake generation in this part (Biswas, 2005, 2014). The region has experienced few large earthquakes in 1819, 1845 and 1956 in the recent past and a devastating earthquake of Mw 7.7 in 2001 (Rastogi et al., 2001, 2004). The seismicity map of the region clearly indicates that aftershock activity is still considerable in the Kachchh region after the 2001 Bhuj earthquake (Chopra et al., 2008; Rastogi et al., 2012). The Kachchh rift basin is filled with the sediments from middle Jurassic to Holocene with its shoulders at Nagar Parker Fault (NPF) in the north and North Kathiawar Fault (NKF) in the south (Biswas, 1987; Biswas and Khatri, 2002). The uplifted area in southern part is called Kachchh Mainland and the uplifted area located in the southeast is

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Wagad, while the low-lying salt encrusted areas in the north is termed as Rann (Biswas, 1987, Merh, 1995, Malik et al., 1999 and GSI, 2000, Chandrashekhar and Mishra, 2002). Tectonically, Kachchh region has many active faults/thrusts; Katrol Hill Fault (KHF), Kachchh Mainland Fault (KMF), Banni Fault (BF), Island Belt Fault (IBF), Allah Bund Fault (ABF), NPF, South Wagad Fault (SWF), North Wagad Fault (NWF), Gedi Fault (GF) and Vigodi Fault (VF) (Biswas, 1987, 2005; Biswas and Khatri, 2002, Pande et al., 2003; Thakkar et al., 2012; Kothyari et al., 2016a, 2016b, 2016c) (Fig. 1). Three deformation zones, 0.5 km–6 km, has been identified along the SWF on the basis of surface geomorphology (Kothyari et al., 2016b; Malik et al., 2017). The features like active fault scarp, river channel shifting and upliftment are indicators of active deformation along GF zone (Kothyari et al., 2016c). The active nature of NWF has been demarcated by the presence of secondary fault scarp, tensional fractures and lateral slip in the vicinity (Kothyari et al., 2015). Being a part of the stable continental region, it is necessary to understand the deformation as well as strain accumulation process in this part of India. Global Positioning System (GPS), nowadays, is a very useful tool used globally for monitoring local as well as regional deformation, which is enabling researchers to assess the seismic hazard of a region. Post-seismic deformation caused by 2001 Bhuj earthquake was monitored by several research groups (Jade et al., 2002, 2003;

Corresponding author. Institute of Seismological Research, Gandhinagar, Gujarat, India. E-mail address: [email protected] (R.K. Dumka).

https://doi.org/10.1016/j.quaint.2019.01.032 Received 14 November 2018; Received in revised form 18 December 2018; Accepted 24 January 2019 Available online 26 January 2019 1040-6182/ © 2019 Elsevier Ltd and INQUA. All rights reserved.

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Fig. 1. (A) Location of the study area towards the western India (B) Three major failed rifts: Kachchh, Cambay and Narmada towards the study area (modified after, Biswas, 1987). The dotted rectangle represents the Kachchh region along with the location of GPS sites (black triangles) and major Fault lines (after, Pande et al., 2003; Biswas, 2005; Thakkar et al., 2012). Red stars represent the location of large earthquakes of 1819, 1845, 1956 and 2001 in the recent past. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

are IISC (Bangalore-India), HYDE (Hyderabad-India), KIT3 (Kitab-Uzbekistan), LHAZ (Lhasa-China), DGAR (Diego-Garcia-Island- U.K.), TEHN (Tehran-Iran), KUNM (Kunming-China), URUM (Urumqi-China), POL2 (Bishkek-Kyrghyzstan), COCO (Cocos Island-Australia), DARW (Darwin- Australia), KARR (Karratha-Australia), SELE (Almaty-Kazakstan), and MALI (Malindi-Kenya). To account for temporal correlation in time series estimates, including monument instability, we have used random walk noise at the level of 0.75 mm yr 1/2 (Mao et al., 1999). Random walk noise is cumulative disturbances from the soils and weather disruption to geodetic monument with respect to the crust (Johnson and Agnew, 1995). Because of the varying conditions of the anchoring media, the instability of geodetic monument is considered a significant source of random walk noise (Williams et al., 2004). Global Mapping Function (GMF) and apriori pressure-temperature from the GPT2 model in absence of meteorological data (Boehm et al., 2006; Lagler et al., 2013) have been used. The ocean tide model FES2004 has been used to eliminate the involvement of ocean tides. For the correction of site displacement associated with the solid earth deformation by tidal potential, the IERS2003 model has been applied during processing (McCarthy and Petit, 2004). To obtain a consistent set of coordinates and their velocities estimation, the outliers were identified from the time series for all the sites and down-weighted for a combined solution. The time series of all the stations of Kachchh region are generated for all the years along with the two IGS sites of Indian plate (Fig. 2). Further, to understand the strain pattern the calculated motion of the sites with respect to the Indian plate was used for strain analysis. While calculating strain, a significance test was conducted using various grid intervals, that is, 8, 10, 12, 15, 20 km and finally, we chose 8 km grid interval as it is most significant for strain analysis of the study area. The significance test is a function that detects the points which can be considered as actual representative of a local strain at the selected scale. Significance test suggests the spatial distribution of the GPS points around the grid point at distance lower or equal to the scale factor. If there are three GPS points in 120-degree area around the grid point at distance lower or equal to the scale factor then it has high significance (e.g., Pesci and Teza, 2007). Based on this, we have categorized the whole region into three zones, most significant, mid-significant and

Likhar et al., 2007; Reddy and Sunil, 2008; Chandrasekhar et al., 2009; Choudhury et al., 2013; Reddy et al., 2013) using campaign mode GPS surveys. However, to understand the tectonic process along with the deformational pattern in the region, long-term analysis of GPS data is necessary. Especially, in the intra-plate regions, having low deformation, GPS data with longer time series is considered to be good. In the present study, an attempt has been made to estimate the crustal deformation rates utilizing data of ten continuous and 5 campaign mode GPS stations. Based on the time series analysis of the GPS data collected using the Leica system 1200 between 2009 and 2015, we calculated the crustal deformation and strain rate.

2. Methodology and GPS data processing Site selection is the most important part of any scientific endeavor, especially when the requirement is to monitor deformation with mm level of accuracy. All the sites for the establishment of GPS stations were selected after a detailed geological and tectonic reconnaissance with the aim to determine minimum and maximum strain in the region. After finalizing sites, RCC monuments at all the sites were constructed and antenna platform was fixed at the top of RCC column and antenna was directly attached to the platform (Figure S1). All the sites are equipped with Leica 1200 receivers and AX1202GG antennas and sampling interval is kept at 30 s with 150elevation mask. GPS data has been generated throughout the year from continuous mode sites while twice a year (minimum 14 days) from the campaign mode sites. In the present study we have used 10 continuous and 5 campaign mode sites for the analysis. The processing of the GPS data starts with the conversion of raw data into the RINEX (Receiver Independent Exchange) format. The data were post-processed using GAMIT-GLOBK software (King and Bock, 1998; Herring et al., 2010) to obtain constrained solution (H) files of parameter estimates and co-variances (Herring et al., 2006). In GAMIT, Zenith tropospheric delay for each station was estimated by a linear model with stochastic constraints for the signal delay due to the troposphere. The basic input of GAMIT are the observation files of permanent/IGS stations in the RINEX format, orbital file or gfiles (sp3/g-files) and the Global Navigation files (SOPAC, sopac.ucsd. edu; CORS, www.ngs.noaa.gov). The IGS stations used for the analysis 296

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Fig. 2. (a) Generated time series of the GPS sites, BELA, KHAV, BHAC, DESA, VKOT, and KUAR in the study area. (b) Time series of BADA, RAPA, VAND and VAMK along with the IGS sites, IISC, HYDE of the Indian plate.

3. Results

low-significant. The results considered in the present study are from the most and mid-significant areas only. After strain calculation, we found that most of the north and eastern part comes under most-significant areas while most of the south-western part comes under mid significant areas. Based on this, we have calculated the strain on the knots in the significant area only via Least Square (LS) method using the grid strain (Pesci and Teza, 2007; Pesci et al., 2009). The computation is based on the rescaling of the covariance matrix of velocity data by a weighting function and gets into consideration the distances among the GPS sites and grid knot (Shen et al., 1996; Pesci et al., 2009). Errors are re-scaled by means of weight function, exp (δd/d0), where d is the distance between the knot and d0 is the smoothing constraint (Shen et al., 1996; Pesci and Teza, 2007; Pesci et al., 2009).

The velocities of all the stations were estimated in the ITRF08 reference frame after combining daily solutions of the sites along with IGS sites (Fig. 3). The average ITRF velocity of the sites in Kachchh region is 49.14 ± 0.14 mm/yr, with one sigma uncertainty (see, Fig. 3, Table 1). For the estimation of deformation patterns, the motion of all the GPS sites was calculated using the Euler pole of Indian plate given by Ader et al. (2012) and Mahesh et al. (2012) (Table 1). However, for further analysis and discussion, we considered the results with respect to Ader et al. (2012) in the present study (Fig. 4). Analysis of GPS time-series, between 2009 and 2015, indicate a low amount of deformation in this part of the Indian plate. A maximum and minimum motion of 3.0 and 297

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Fig. 3. Velocities of all the stations were estimated in the ITRF08 reference frame after combining daily solutions of the sites along with IGS sites. The average ITRF velocity of the sites (blue arrows for continuous and black arrows for campaign mode) in Kachchh region is 49.1 ± 0.14 mm/yr, with one sigma uncertainty. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

(2008) and Chandrasekhar et al. (2009). An analysis reveals that the post-seismic deformation is very low in the Kachchh region (Chaudhary et al., 2013; Dumka et al., 2018c). The calculated strain rate tensors indicate that most of the Kachchh region predominantly is under N-S compression, expected in the Indian plate tectonics (Fig. 5). The strain calculated near the fault trace of KMF and KHF indicates Strike Normal Compression (SNC). Similar, strike normal compression is observed in case of SWF and GF (Fig. 5). The maximum compressional strain of 5 nano-strain/yr is observed towards the northeastern part of the 2001 earthquake epicenter (Fig. 5). The amount is less than the strain of 7 nano-strain/yr observed by Reddy and Sunil (2008) but little higher in context to the strain rates of intra-plate regions (Dixon et al., 1996; Calais et al., 2006; Mazotti, 2007; Sella et al., 2007). However, a small variation in the direction of strain-tensor is observed between the eastern and western Kachchh. Towards eastern part, the strain tensors are almost N-S while towards west these are NW-SE directed (Fig. 5).

0.5 mm/yr respectively, has been observed in the Kachchh region (Table 1). The variation in the deformation rate is due to the nonuniform slip rate of the faults in the region. Based on the results it can be concluded that the northern part of the study area has accommodated maximum amount of deformation during the observation period. Although, the amount of deformation is very low as compared to the deformation rate of Indian plate boundary (e.g. Ader et al., 2012; Mahesh et al., 2012; Dumka et al., 2014a, 2014b; Jade et al., 2014; Kundu et al., 2014; Jade et al., 2017; Dumka et al., 2018a) but, is significant in context to the stable continental regions (Calais et al., 2006; Mazzotti, 2007; Mahesh et al., 2012; Catherine et al., 2015, Dumka et al., 2018b, 2018c). The results indicate variation in motion of sites from south to north in Kachchh region. The sites located towards the north from the epicenter of 2001 earthquake indicate a higher rate of deformation as compared to those in the south. GPS derived deformation shows good correlation with the seismicity of the study area (see Fig. 4). Previous GPS measurements carried out in the campaign mode suggest 12 mm/yr of horizontal deformation for the first 6 months after 2001 Bhuj earthquake, which reduces to 6, 3, and 4 mm/yr subsequently (Jade et al., 2002, 2003; Reddy and Sunil, 2008; Chandrasekhar et al., 2009; Choudhury et al., 2013). The decaying nature of the post-seismic motion with a total displacement of as much as 29 mm during 2002–2007 was measured using the GPS time series (Chandrasekhar et al., 2009). To understand the decay pattern of the post-seismic deformation since 2001 earthquake, a composite time series has been generated using the 9 years of data together with the available results of Reddy and Sunil

4. Discussion The results of present study indicate a low amount of deformation in the Kachchh region, zone of substantial seismic activity, towards the western part of the Indian plate. Based on the GPS results, Calais et al. (2006) and Mazzotti (2007) reveals that the low amount of deformation is expected in the intra-plate region and Mahesh et al. (2012) mentioned that any deformation ≈ 1.5 mm/yr is significant for the Indian plate. GPS study in the Godavari rift, an intra-plate region of Indian plate, revealed less than 1.5 mm/yr of deformation (Mahesh et al.,

Table 1 Detail of GPS sites along with estimated deformation rates. The deformation rates DM and DA indicates calculation using the Euler pole given by Mahesh et al. (2012) and Ader et al. (2012), respectively. © indicates campaign mode sites. SITE

LONG

LAT

VEL(ITRF08)mm/yr

Deformationrate (DM)mm/yr

Sigma mm/yr

Deformationrate (DA)mm/yr

Sigma mm/yr

BELA DESA RAPA BADA VAMK BHAC KHAV KUAR VAND VKOT HUBA© CHAD© DUDH© JNGR© PALN©

70.8 70.6 70.6 70.5 70.4 70.3 69.7 69.7 69.3 69.2 69.8 70.1 70.14 70.01 69.57

23.87 23.74 23.56 23.47 23.43 23.30 23.92 23.99 23.02 24.2 23.4 23.3 23.32 23.36 23.44

47.2 48.3 48.1 48.3 48.8 48.8 47.2 46.3 49.1 47.1 49.2 49.2 49.5 49.1 49.2

2.25 1.53 0.75 0.64 1.61 0.55 2.91 2.08 0.67 1.51 1.39 1.07 1.16 1.36 0.69

0.12 0.12 0.14 0.12 0.12 0.14 0.12 0.10 0.16 0.12 0.22 0.26 0.28 0.22 0.38

1.80 0.96 0.76 0.52 0.97 0.08 3.61 2.03 0.64 1.16 1.32 1.10 1.23 1.25 0.85

0.12 0.12 0.14 0.10 0.10 0.10 0.18 0.12 0.12 0.12 0.28 0.22 0.32 0.32 0.28

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Fig. 4. Calculated deformation rates of the GPS sites. For the calculation, Euler pole given by Ader et al. (2012) was applied. The multidirectional motion of GPS sites indicate localized motion along the faults. Open circles represent the locations of earthquakes (Chopra et al., 2008; ISR, 2013).

KMF, the KHF and near the vicinity of KMF and SWF, respectively. More recently in 2006, one Mw 5.6 and Mw 5.0 earthquakes occurred along the GF and IBF, respectively. We presume that this kind of earthquake occurrences along the different fault indicate the existence of a weak zone. The low amount of deformation of a weak zone may trigger large earthquake after accelerated by the regional compression. A field-based geomorphological investigation by Kothyari et al. (2016c) mentioned that GF zone is under compressive stress. The derived N-S strain rate tensor of the present study indicates the existence of regional compression as per the Indian plate tectonics. The maximum strain rate of 7 nano-strain/yr was observed near the epicenter of 2001, Bhuj earthquake (Reddy and Sunil, 2008) and now in the present study, a maximum of 5 nano-strain/yr is observed towards NE of the epicenter. This kind of strain migration again indicates the deformation in weak zones. OSL chronology of southern part of Wagad indicates an uplift rate of 2.8 mm/yr (Kothyari et al., 2016b). Similarly, the seismic activity after 2008 along the IBF and GF, towards N/NE of 2001 epicentral zone, has increased (Rastogi et al., 2012; Kothyari et al., 2016c; Singh et al., 2016; Kothyari et al., 2018; Dumka et al., 2018c). Based on the seismicity and GPS derived observations we

2012). Similarly, the Koyna region, the epicenter of 1967, M 6.3 earthquake, registered < 2.0 mm/yr of deformation within the Indian plate (Catherine et al., 2015). Geodetic studies of most of the Stable Continental Regions (SCR) suggest very low, between 0.2 and 0.6 mm/ yr, amount of deformation (Calais et al., 2006; Calais and Stein, 2009; Ziegler, 1992; Schumacher, 2002; Landgraf et al., 2017; Nocquet and Calais, 2003; Nocquet, 2012; Hackl et al., 2011; Saria et al., 2013). The north China, interior of the Eurasian plate, has the complete historical records of earthquakes and strong earthquakes, indicates deformation rate of < 1.0 mm/yr (Xu and Shen, 1981; Meng et al., 2006). The occurrence of several significant earthquakes in the Australian Plate indicates strain release, associated with the east-west shortening (Smith et al., 1990) reveals 0.3–0.4 mm/yr of deformation (Tregonning, 2003; Leonard, 2008). Therefore, it can be concluded that the deformation rate of Kachchh region, Indian plate, is among the highest as compared to other SCR of the world. The epicenters of the large earthquakes in this part indicate that they are not generated from the same source. For example, 1819 (Mw 7.8, Allah Bund), 1945 (Mw 6.3, Lakhpat), 1956 (Mw 6.0, Anjar) and the recent 2001 (Mw 7.7 Bhuj) occurred along the ABF, western part of

Fig. 5. The calculated strain rate tensors indicate that most of the Kachchh region is under N-S compressional regime. The red and blue lines of strain tensor indicate compression and extension, respectively. All the calculated strain tensors are under the most significant areas except strain tensors (dotted), which falls under mid-significant area. The symbol triangle and circle show the location of continuous and campaign mode sites, respectively. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

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presume that in the failed rift region (weak zone), the strain is not able to sustain for the longer time period and getting released at any place. The multidirectional motion of sites (see Fig. 4) of the present study supports the localized deformation and may indicate variable slip along the faults. The fault geometry of SWF is itself responsible for variation in the stress regime in the Wagad region (Kothyari et al., 2016a). A recent magnetotelluric study suggests presence of fluid, controlled by faults, is playing an important role in the earthquake genesis in the study area (Pavan Kumar et al., 2017). Biswas (1987) already mentioned that the Radhanpur arch is acting as a local stress barrier for the Kachchh region, also the work carried out by the Talwani (2017) highlighted the importance of local stress concentrators. The structural in-homogeneity is suitable for the local stress concentration in the upper crust (Sykes, 1978; Talwani and Rajendran, 1991; Kenner and Segall, 2000). Nevertheless, it is important to understand the intra-plate mechanism of earthquake genesis processes in this region, which have to be investigated in future by detailed analysis of GPS time series.

Biswas, S.K., 2005. A review of structure and tectonics of Kutch basin, western India, with special reference to earthquakes. Curr. Sci. 88, 1592–1600. Biswas, S.K., 2014. Active tectonics of western continental margin of Indo Pak craton, stress source for SCR earthquakes. J. Earthq. Sci. Eng. 1, 46–58. Biswas, S.K., Khattri, K.N., 2002. A geological study of Earthquakes in Kutch, Gujarat, India. J. Geol. Soc. India 60, 131–142. Boehm, J., Niell, A., Tregoning, P., Schuh, H., 2006. Global mapping function GMF: a new empirical mapping function based on numerical weather model data. Geophy. Res. Lett. 33. https://10.1029/2005GL025546. Calais, E., Stein, S., 2009. Time variable deformation in the New Madrid seismic zone. Science 323, 1442. Calais, E., Dong, L., Wang, M., Shen, Z., Vergnolle, M., 2006. Continental deformation in Asia from a combined GPS solution. Geophy. Res. Lett. 33. https://doi:10.1029/ 2006GL028433. Catherine, J.K., Gahalaut, V.K., Kundu, B., Ambikapathy, A., Yadav, R.K., Bansal, A., Narsaiah, M., Naidu, S.M., 2015. Low deformation rate in the Koyna-Warna region, a reservoir triggered earthquake site in west-central stable India. J. Asian Earth Sci. 97, 1–9. Chandrasekhar, D.V., Mishra, D.C., 2002. Some geodynamic aspects of Kutch basin and seismicity: insight from gravity studies. Curr. Sci. 83, 492–498. Chandrasekhar, D.V., Bürgmann, R., Reddy, C.D., Sunil, P.S., Schmidt, D.A., 2009. Weak mantle in NW India probed by geodetic measurements following the 2001 Bhuj earthquake. Earth Planet. Sci. Lett. https://doi:10.1016/j.epsl.2009.01.039. Chopra, S., Yadav, R.B.S., Patel, H., Kumar, S., Rao, K., Rastogi, B.K., Hameed, A., Srivastava, S., 2008. The Gujarat (India) seismic network. Seismol. Res. Lett. 79, 806–815. Choudhury, P., Catherine, J.K., Gahalaut, V.K., Chopra, S., Dumka, R.K., Roy, S., 2013. Post-seismic deformation associated with the 2001 Bhuj earthquake. Nat. Haz. 65, 1109–1118. Dixon, T.H., Mao, A., Stein, S., 1996. How rigid is the stable interior of the north American plate. Geophys. Res. Lett. 23, 3035–3038. Dumka, R.K., Kotlia, B.S., Kumar, K., Satyal, G., Joshi, L.M., 2014a. Crustal deformation revealed by GPS in Kumaun Himalaya, India. J. Mountain Sci. 11, 41–50. Dumka, R.K., Kotlia, B.S., Kumar, K., Satyal, G., 2014b. Quantification of crustal strain rate in Kumaun Himalaya (India) using GPS measurements of crustal deformation. Him. Geol. 35, 146–155. Dumka, R.K., Kotlia, B.S., Kothyari, G.C., Paikray, J., Dimri, S., 2018a. Detection of high and moderate crustal strain zones in Uttarakhand Himalaya, India. Acta Geod. Geophys. https://doi.org/10.1007/s40328-018-0226-z. Dumka, R.K., Chodhury, P., Gahalaut, V.K., Gahalaut, K., Yadav, R., 2018b. GPS measurements of deformation caused by seasonal filling and emptying cycles of four hydroelectric reservoirs in India. Bull. Seismol. Soc. Am. https://doi.org/10.1785/ 0120170355. Dumka, R.K., Kotlia, B.S., SuriBabu, D., Narain, P., Prajapati, S., 2018c. Present-day crustal deformation and geodetic strain in the vicinity of Dholavira - Harappan civilization site, Kachchh, western part of the Indian plate. Quat. Int. https://doi.org/ 10.1016/j.quaint.2018.10.035. Geological Survey of India (GSI), 2000. Seismotectonic atlas of India and its environs. Geological Survey of India, Sp. Pub., Calcutta, pp. 88. Hackl, M., Malservisi, R., Hugentobler, U., Wonnacott, R., 2011. Estimation of velocity uncertainties from GPS time series: examples from the analysis of the South African Trig-Net network. J. Geophys. Res. 116. https://doi/10.1029/2010JB008142. Herring, T., King, R.W., McClusky, S.C., 2006. GAMIT reference manual, GPS analysis at MIT, release 10.3. department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology Cambridge, pp. 33. Herring, T.A., King, R.W., McClusky, S.C., 2010. Introduction to GAMIT/GLOBK, department of Earth, Atmospheric and Planetary Sciences. Massachusetts Institute of Technology Cambridge, pp. 50. Institute of Seismological Research (ISR), 2013. annual report. http://www.isr.gujarat. gov. Jade, S., Mukul, M., Parvez, I.A., Ananda, M.B., Dileep, K.P., Gaur, V.K., 2002. Estimates of co-seismic displacement and post-seismic deformation using GPS geodesy for the Bhuj earthquake of 26 January 2001. Curr. Sci. 82, 748–752. Jade, S., Mukul, M., Parvez, I.A., Ananda, M.B., Dileep, K.P., Gaur, V.K., Bendick, R., Bilham, R., Blume, F., Wallace, K., Abbasi, I.A., Khan, M.A., Ulhadi, S., 2003. Preseismic, co-seismic and post-seismic displacements associated with the Bhuj 2001 earthquake derived from recent and historic data. Proc. Indiana Acad. Sci. 112, 331–345. Jade, S., Mukul, M., Gaur, V.K., Kumar, K., Shrungeshwar, T.S., Satyal, G.S., Dumka, R.K., Jagannathan, S., Ananda, M.B., Kumar, P.D., Banerjee, S., 2014. Contemporary deformation in the Kashmir–Himachal, Garhwal and Kumaon Himalaya: significant insights from 1995-2008 GPS time series. J. Geodes. https://doi/10.1007/s00190014-0702-3. Jade, S., Shrungeshwara, T.S., Kumar, K., Choudhury, P., Dumka, R.K., Bhu, H., 2017. India plate angular velocity and contemporary deformation rates from continuous GPS measurements from 1996 to 2015. Sci. Rep. https://dOI:10.1038/s41598-01711697-w. Johnson, H.O., Agnew, D.C., 1995. Monument motion and measurements of crustal velocities. Geophys. Res. Lett. 22, 2905–2908. Kenner, S.J., Segall, P., 2000. A mechanical model for intraplate earthquakes: application to the New Madrid seismic zone. Science 289 (80), 2329–2332. https://doi.org/10. 1126/science.289.5488.2329. King, R.W., Bock, Y., 1998. Documentation for the GAMIT GPS processing software release 10.0. Massachusetts Institute of Technology, Cambridge, pp. 136. Kothyari, G.C., Rastogi, B.k., Dumka, R.K., Chauhan, m., 2015. Secondary surface deformation along the Bharudia/North Wagad Fault Zone in Kachchh rift basin, western

5. Conclusions We present the GPS derived deformation rates utilizing data of 10 continuous and 5 campaign mode GPS sites in the western part of the Indian plate. We have quantified the deformation and strain rates in the seismically active part of the Indian plate. Results of our study reveal that the deformation in this part of the western continental margin of India (WCMI) is low. The velocity of Kachchh deduced from these sites indicates 46–51 mm/yr in the ITRF08 reference frame. Most of the sites indicate deformation rate < 3 mm/yr, which is significant in the context of the stable continental region. The multi-directional motion of GPS sites supports the localized deformation and may indicate variable slip along the faults. However, the dominance of N-S compression strain highlights the role of present-day tectonics of Indian plate. The calculated strain rate for the Kachchh region is found to be a maximum 5 nano-strain/yr towards the N/NE part. The analysis of strain tensors near the fault systems (KMF, KHF, SWF and GF) indicates a major component of dip-slip motion along the faults in the eastern part. Acknowledgments The author is thankful to DG, Institute of Seismological Research (ISR), Gandhinagar for their encouragement. RKD thankfully acknowledge DST (GoG) and MoES (GoI) for the financial assistance. RKD is grateful to Mr. Shivraj Jadeja, Bhachu for his support during the installation of GPS sites. Earthquake locations were taken from the monitoring program of ISR (http://www.isr.gujarat.gov.in/monitoring_ prg) and Chopra et al. (2008). IGS, brdc and sp3 data used for the GPS data processing were downloaded from the SOPAC (http://sopac.ucsd. edu) and NOAA (ftp://geodesy.noaa.gov/cors). We thankfully acknowledge Department of Science and Technology, Govt of Gujarat and Ministry of Earth Sciences, Govt of India for the financial assistance under the AFM program (Seismo-1/270/AFM/2015; comp.VII)" instead of "RKD thankfully acknowledge DST (GoG) and MoES (GoI) for the financial assistance. Appendix A. Supplementary data Supplementary data to this article can be found online at https:// doi.org/10.1016/j.quaint.2019.01.032. References Ader, T., Avouac, J.P., Liu-Zeng, J., Lyon-Caen, H., Bollinger, L., Galetzka, J., Genrich, J., Thomas, M., Chanard, K., Sapkota, S., Rajaure, S., Shrestha, P., Ding, L., Flouzat, M., 2012. Convergence rate across the Nepal Himalaya and interseismic coupling on the Main Himalayan Thrust: implications. J. Geophy. Res. 117, B04403. Biswas, S.K., 1987. Regional tectonic framework, structure and evolution of the western marginal basins of India. Tectonophysics 135, 307–327.

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2017GL072936. Pesci, A., Teza, G., 2007. Strain rate analysis over the central Alpennines from GPS velocities: the development of a new free software. Boll. Geod. Sci. Affini 56, 69–88. Pesci, A., Giordano, T., Giuseppe, C., 2009. Improving strain rate estimation from velocity data of non-permanent GPS stations: the central Alpennine study case (Italy). GPS Solut. 13, 249–261. Rastogi, B.K., 2004. Damage due to the Mw 7.7 Kutch, India earthquake of 2001. Tectonophysics 390, 85–103. Rastogi, B.K., Gupta, H.K., Mandal, P., Satnarayana, H.V.S., Kousalya, M., Raghavan, R., Jain, R., Sharma, A.N.S., Kumar, N., Satyamurty, C., 2001. The deadliest stable continental region earthquake occurred near Bhuj on 26 January 2001. J. Seismol. 5, 609–615. Rastogi, B.K., Choudhury, P., Dumka, R.K., Sreejith, K.M., Majumdar, T.J., 2012. Stress pulse migration by viscoelastic process for long distance delayed triggering of shocks in Gujarat, India, after the 2001 Mw 7.7 Bhuj earthquake. AGU Monograph, pp. 1–14. Reddy, C.D., Sunil, P.S., 2008. Post seismic crustal deformation and strain rate in Bhuj region, Western India, after the 2001 January 26 earthquake. Geophys. J. Int. 172, 593–606. Reddy, C.D., Sunil, P.S., Bürgmann, R., Chandrasekhar, D.V., Kato, T., 2013. Postseismic relaxation due to Bhuj earthquake on January 26, 2001: possible mechanisms and processes. Nat. Haz. 65, 1119–1134. Saria, E., Calais, E., Altamimi, Z., Willis, P., Farah, H., 2013. A new velocity field for Africa from combined GPS and DORIS space geodetic solutions: contribution to the definition of the African reference frame (AFREF). J. Geophys. Res. Solid Earth 118, 1677–1697. https://doi:10.1002/jgrb.50137. Schumacher, M.E., 2002. Upper Rhine graben: the role of preexisting structures during rift evolution. Tectonics 21, 6–17. https://doi.org/10.1029/2001TC900022. Sella, G.F., Stein, S., Dixon, T.H., Craymer, M., James, T.S., Mazzotti, S., Dokka, R.K., 2007. Observation of glacial isostatic adjustment in ‘‘stable’’ north America with GPS. Geophys. Res. Lett. 34. https://doi:10.1029/2006GL027081. Shen, Z.K., Jackson, D.D., Ge, B.X., 1996. Crustal deformation across and beyond the Los Angeles basin from geodetic measurements. J. Geophys. Res. 101, 27957–27980. Singh, A.P., Kumar, S., Mishra, S., 2016. Inversions for earthquake focal mechanisms and regional stress in the Kachchh rift basin, western India: tectonic implications. J. Asian Earth Sci. 117, 269–283. Smith, D.E., Kolenkiewicz, R., Dunn, P.J., Robbins, J.W., Torrence, M.H., Klosko, S.M., Willimamson, R.G., Pavlis, E.C., Douglas, N.B., Fricke, S.K., 1990. Tectonic motion and deformation from SLR to LAGEOS. J. Geophys. Res. 95. https://doi/10.1029/ JB095iB13p22013. Sykes, L.R., 1978. Intraplate seismicity, reactivation of preexisting zones of weakness, alkaline magmatism, and other tectonism postdating continental fragmentation. Rev. Geophys. 16, 621–688. https://doi.org/10.1029/RG016i004p00621. Talwani, P., 2017. On the nature of intraplate earthquakes. J. Seismol. 21, 47. https://doi. org/10.1007/s10950-016-9582-8. Talwani, P., Rajendran, K., 1991. Some seismological and geometric features of intraplate earthquakes. Tectonophysics 186, 19–41. http://doi.org/10.1016/0040-1951(91) 90383-4. Thakkar, M.G., Ngangom, M., Thakkar, P.S., Juyal, N., 2012. Terrain response to the 1819 Allah Bund earthquake in western Great Rann of Kachchh Gujarat, India. Curr. Sci. 103, 108–112. Tregoning, P., 2003. Is the Australian Plate deforming? A space geodetic perspective, vol 22. Geological Society of Australia and Geological Society of America, Sp. Pub., pp. 41–48. Williams, S., Bock, Y., Fang, P., Jamason, P., Nikolaidis, R., Prawirodirdjo, L., Miller, M., Johnson, D., 2004. Error analysis of continuous GPS position time series. J. Geophys. Res. 109. https://doi:10.1029/2003jb002741. Xu, S., Shen, P., 1981. Seismicity patterns in China, in earthquake prediction, an international review. In: Maurice Ewing Series, vol. 4. AGU, pp. 117–125. Ziegler, P.A., 1992. European Cenozoic rift system. Tectonophysics 208, 91–111.

India. Comunicações Geol. 102 (1), 15–27. Kothyari, G.C., Dumka, R.K., Singh, A.P., Chauhan, G., 2016a. Tectonic evolution and stress pattern of South Wagad Fault at the Kachchh rift basin in western India. Geol. Mag. 154, 875–887. Kothyari, G.C., Rastogi, B.K., Morthekai, P., Dumka, R.K., Kandregula, R.S., 2016b. Active segmentation assessment of the tectonically active South Wagad Fault in Kachchh, Western Peninsular India. Geomorphology 253, 491–507. Kothyari, G.C., Rastogi, B.K., Morthekai, P., Dumka, R.K., 2016c. Landform development in a zone of active Gedi Fault, eastern Kachchh rift basin, India. Tectonophysics 670, 115–126. Kothyari, G.C., Shirvalkar, P., Kandregula, R.S., Rawat, Y.S., Dumka, R.K., Joshi, N., 2018. Holocene tectonic activity along Kachchh Mainland Fault: Impact on late mature Harappan civilization, Kachchh, western India. Quat. Int. https://doi:10. 1016/j.quaint.2018.10.032. Kundu, B., Yadav, R., Bali, V., Chodhury, S., Gahalaut, V.K., 2014. Oblique convergence and slip partitioning in the NW Himalaya: implications from GPS measurements. Tectonics. https://doi:10.1002/2014TC003633. Lagler, K., Schindelegger, M., Böhm, J., Krásná, H., Nilsson, T., 2013. GPT2: empirical slant delay model for radio space geodetic techniques. Geophys. Res. Lett. 40, 1069–1073. https://doi:10.1002/grl.50288. Landgraf, A., Kübler, S., Hintersberger, E., Stein, S., 2017. Active tectonics, earthquakes and palaeoseismicity in slowly deforming continents. Geol. Soc. London, Spec. Publ. 432, 1–12. https://doi.org/10.1144/SP432.13. Leonard, M., 2008. One hundred years of earthquake recording in Australia. Bull. Seismol. Soc. Am. 98, 1458–1470. Likhar, S., Kulkarni, M.N., Sakr, K., 2007. Crustal deformation studies in the area of the 26th January 2001 earthquake in Bhuj region of Gujarat. J. Geol. Soc. India 70, 912–916. Mahesh, P., Catherine, J.K., Kundu, B., Ambikapathy, A., Bansal, A., 15 others, 2012. Rigid Indian plate: constraints from GPS measurements. Gond. Res. 22, 1068–1072. Malik, J.N., Sohani, P.S., Karant, R.V., Merh, S.S., 1999. Modern and historic seismicity of Kachchh peninsula, western India. J. Geol. Soc. India 54, 545–550. Malik, J.N., Gadhavi, M.S., Kothyari, G.C., Satuluri, S., 2017. Paleo-earthquake signatures from the South Wagad Fault (SWF), Wagad Island, Kachchh, Gujarat, western India: A potential seismic hazard. J. Struct. Geol. 95, 142–159. Mao, A.C., Harrison, C., Dixon, T., 1999. Noise in GPS coordinate time series. J. Geophys. Res. 104, 2797–2816. Mazzotti, S., 2007. Geodynamic models for earthquake studies in intra-plate north America. In: In: Stein, S., Mazzotti, S. (Eds.), Continental Intraplate Earthquakes: Science, Hazard, and Policy Issues, vol 425 Geological Society of America, Sp. Pap. https://doi:10.1130/2007.2425(02). McCarthy, D.D., Petit, G., 2004. IERS technical note; 32 Frankfurt am main, vol 127 Verlag des Bun desamt sfür Kartographie und Geodäsie ISBN 3-89888-884-3. Meng, G., Shen, X., Wu, J., Rogozhin, E.A., 2006. Present-day crustal motion in northeast China determined from GPS measurements. Earth Planets Space 58, 1441–1445. Merh, S.S., 1995. Geology of Gujarat. Geological Society of India, Bangalore, India, pp. 222. Molnar, P., Tapponier, P., 1975. Cenozoic tectonics of Asia: effects of a continental collision. Science 189, 419–425. Nocquet, J.M., 2012. Present-day kinematics of the Mediterranean: a comprehensive overview of GPS results. Tectonophysics 578, 220–242. Nocquet, J.M., Calais, E., 2003. Crustal velocity field of western Europe from permanent GPS array solutions, 1996–2001. Geophys. J. Int. 154, 72–88. Pande, P., Kayal, J.R., Joshi, Y.C., Ghevariya, Z.G., 2003. Lithotectonic framework of Gujarat and adjoining regions. In: Kutch (Bhuj) earthquake 26 January, 2001, vol 76. Geological Survey of India, Sp. Pub., pp. 5–11. Pavan Kumar, G., Mahesh, P., Nagar, M., Mahender, E., Kumar, V., Mohan, K., Kumar, M.R., 2017. Role of deep crustal fluids in the genesis of intraplate earthquakes in the Kachchh region, northwestern India. Geophys. Res. Lett. http://doi.org/10.1002/

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