Figure 7 - uploaded by N. Suresh
Content may be subject to copyright.
Earthquake faults: a, Panoramic view of the trench wall (with 1 m grid) showing two distinct faults (F–F shown with arrows), where the Middle Siwalik sandstone (MSw) thrust over the Late Pleistocene sediments (LPs) along HFT, Kala Amb. b, c, Close-up views of part of the two palaeoearthquake faults (Fault-I, the older and Fault-II, the younger) observed in the trench. Depositional contact of the Quaternary alluvium with the Middle Siwaliks is shown by shaded lines 13 .
Source publication
The Himalayan region has experienced a number of M8 and M5-M7.8 magnitude earthquakes in the present century. Apart from the release of strain builtup due to convergence of the Indian and Tibetan plates by seismic activity and aseismic slip, the tectonic activity in the current tectonic regime has also effected morphotectonic changes due to uplift,...
Similar publications
The Siwalik foreland deposit was earlier considered as freshwater continental megafan deposit, formed by southward flowing transverse drainages, analogous to modern Kosi-like megafans. However, this analogy remained incomplete due to lack of evidence of a regionally persistent axial stream system or marginal marine depositional system, like the Gan...
Citations
... As discussed previously, local or regional earthquakes have impacted Delhi in the last two centuries from sources associated with both the ADFB and the Himalayan arc. But other frontal faults in the Himalayan Shivalik foothills have also ruptured in multiple large magnitude earthquakes since the Pleistocene (e.g., Philip et al. 2014;Arora et al. 2019). The ground motions to be anticipated in Delhi from future earthquakes on these and other interface or intraslab faults will be significant with local ampliBcation and/or liquefaction in the unconsolidated sediments of the Ganga and the Yamuna Cood plains contributing to the hazard. ...
The Aravalli-Delhi Fold Belt (ADFB) is one of three prominent ridges on the continental part of the Indian plate extending northward from central India and subducting beneath the Himalayan arc. Though it is seismogenic along its entire NE-SW structural trend, activity varies spatially with a noteworthy region of higher seismicity in the vicinity of Delhi. We analyse historical and modern instrumented seismicity. Using recomputed focal mechanisms for events such as the 1956 Bulandshahr earthquake, we found that the maximum principal stress (sigma1) in this region is oriented in the N-S to NE-SW direction, similar to that in the neighbouring Garhwal-Kumaun Himalayas. Our analysis also indicates that the earthquakes along the ADFB occur on steep faults which are parallel or oblique to its NE-SW structural trend and that the entire crust appears to be seismically active as the earthquakes occur up to a depth of ~40 km. Within the better instrumented Delhi region, we observed a pattern in the average monthly frequency of earthquakes recorded that we speculate was modulated by monsoonal recharge of the local water table. The cause of seismicity in the AFDB is still a question for debate, pending better seismological and geodetic instrumentation, but we build on evolutionary models of the ADFB to suggest that seismicity is the consequence of the continued relative motion between the Bundelkhand and Marwar cratons in the northern Indian shield. The nature and causes of earthquakes in this region notwithstanding , the proximity of large cities such as Delhi, Jaipur and Udaipur to poorly-studied or unknown sources of seismic hazard is a concern and warrants further scientific and policy intervention.
... Fault types were defined based on the focal mechanisms obtained from different studies (Sikharulidze et al., 1998;Sahakyan, 2018;Tan and Taymaz, 2006;Tseng et al., 2016). The results of previous geological studies (Adamia et al., 2011(Adamia et al., , 2017Gamkrelidze et al., 1998;Philip et al., 2014) were also assessed. Three types of faults were considered in this study (thrust, normal, and strike-slip). ...
Strong ground motions caused by earthquakes with magnitudes ranging from 3.5 to 6.9 and hypocentral distances of up to 300 km were recorded by local broadband stations and three-component accelerograms within Georgia’s enhanced digital seismic network. Such data mixing is particularly effective in areas where strong ground motion data are lacking. The data were used to produce models based on ground-motion prediction equations (GMPEs), one benefit of which is that they take into consideration information from waveforms across a wide range of frequencies. In this study, models were developed to predict ground motions for peak ground acceleration and 5%-damped pseudo-absolute-acceleration spectra for periods between 0.01 and 10 s. Short-period ground motions decayed faster than long-period motions, though decay was still in the order of approximately 1/r. Faulting mechanisms and local soil conditions greatly influence GMPEs. The spectral acceleration (SA) of thrust faults was higher than that for either strike-slip or normal faults but the influence of strike-slip faulting on SA was slightly greater than that for normal faults. Soft soils also caused significantly more amplification than rocky sites.
... The Main Central Thrust, Main Boundary Thrust, and the Himalayan Frontal Thrust are all parts of a highly active Himalayan fault system that is situated in the north of the study area (Verma and Bansal 2013;Philip et al. 2014). The Munger-Sehersa ridge and Madhubani Purnia depression are tectonic structures in the study area depicted in Figure 2 that have an influence on the region's sedimentation and tectonic history (Dasgupta et al. 1987;Valdiya 2016). ...
Northern Bihar witnessed severe liquefaction events during the 1934 (8.2 Mw) and 1988 (6.9 Mw) earthquakes. This study reconstructed the liquefaction damage scenario due to both earthquakes (1934, 1988). The liquefaction hazard map was prepared using two techniques (1) Rapid Response and Loss Estimation (Model A) and (2) the (Model B) Liquefaction Susceptibility Map (LSM) integrated with the Peak Ground Acceleration (PGA). The LSM was prepared using the multicriteria decision-making technique considering the site-specific thematic layers. The ground motion parameters (PGV and PGA) were retrieved from isoseismal maps prepared for both events. The hazard map prepared using Model B was classified into four classes very low, low, high, and severe, and the results obtained from both models were compared. The area under the curve (AUC) was determined for Model A 0.88 and 0.85 and Model B 0.94 and 0.84 for the 1934 and 1988 earthquakes, respectively. The prepared liquefaction hazard map may help policymakers demarcate the study area according to liquefaction hazard potential and mitigate future hazards.
... The great Nepal-Bihar earthquake of magnitude 8.2 MW in 1934 killed over 15,700 people (8500 in Nepal and 7200 in India) (Sapkota et al., 2016). The Himalayan fault system is made up of three tectonically active faults: the Himalayan Frontal Thrust (HFT), the Main Boundary Thrust (MBT), and the Main Central Thrust (MCT) (Verma and Bansal 2013;Philip et al. 2014). Large depressions separated by ridges trending NE-SW in the central part of the IGP, the Munger-Saharsa ridge fault, and Madhubani and Purnea depression, have influenced the history of sedimentation and tectonics of the foredeep basin since the birth of the Himalayas, according to a detailed review published by Dasgupta et al. (1987) and Valdiya (2016). ...
Earthquakes in the Himalayas pose a significant hazard to the densely populated Indo-Gangetic Plains (IGP). Due to liquefaction of soils, ground settlements and structural tilting are prevalent during earthquakes. This study aims to identify liquefaction potential zones in the North-Bihar region of the East Ganga Plains by performing morphotectonic analysis over six drainage basins and liquefaction susceptibility mapping using Analytical Hierarchy Process (AHP) while taking site-specific parameters into account. The Index of Relative Active Tectonic (IRAT) value for Gandak and Mahananda was determined to be 1, indicating that the basins are extremely active, whereas Burhi Gandak, Bagmati, and Kosi were moderately active with a 2 IRAT value. The Kamla basin is the least active with an IRAT value of 4. The Liquefaction Susceptibility Map (LSM) was divided into three categories: liquefaction not likely (24%), liquefaction possible (45%), and liquefaction likely (31%); the estimated RMSE values were 0.0084, 0.00048, and 0.00031, respectively. The integrated analysis, which employs both techniques, demonstrates how the individual basins will be affected by liquefaction during an earthquake. The proposed methodology would be beneficial to decision-makers when designing strategies for urban planning projects, as well as structural engineers when selecting sites for field-based surveys.
... Beside the MFT, neotectonic activity has been reported at several places in the foothills between the HFT in the south and MBT in the north, prominent being near Hajipur, Nalagarh, Pinjor, Kala Amb and Sundernagar area (Philip et al., 2014, Thakur et al., 2018. ...
... The Himalayan mountain ranges show numerous active tectonic features like faults, uplifts, skewed fans, rivers terraces, stream migration and river capture etc. which aid to evaluate past and active tectonics (Philip, 2014). Evidences of regional tectonic activity during the past 35-40 ka have been reported from the entire Himalayan belt (Cronin, 1982;Burbank and Fort, 1985;Shroder et al., 1986;Valdya, 1988;Cronin, 1989;Fort et al., 1989;Shroder et al., 1993;Sangode and Bagati, 1995;Kotlia et al., 1998;Valdiay, 2001;Phartiyal et al., 2005;Phartiyal and Sharma, 2009;Bali et al., 2003;. ...
Morphometry is a quantitative approach of analysing linear, areal and relief parameters to understand the role of neotectonic activity in geomorphologic evolution of a river basin. In the present study multi-disciplinary integrated approach using morphometric parameters along with remote sensing and GIS technique have been applied for determining the quantitative parameters indicative of neotectonic activity in the Parvati basin, Higher Himalaya. The lineament pattern observed in the basin shows major trend in NESW followed by NW-SE and NNE-SSW directions. The basin is a 6th order drainage basin with dominating dendratic – trellis drainage pattern having very strong structural/tectonic control and is in its late youth stage of geomorphic development. Parvati basin shows coarse drainage density with fine texture suggesting more surface runoff and less infiltration in the area. The basin is highly elongated in shape tapering towards the south-west with high susceptibility to erosion with lower peak flow for longer duration. The above observations clearly indicate a tectonic and lithological control over the evolution of drainage pattern of Parvati basin.
... The Himalayan mountain ranges show numerous active tectonic features like faults, uplifts, skewed fans, rivers terraces, stream migration and river capture etc. which aid to evaluate past and active tectonics (Philip, 2014). Evidences of regional tectonic activity during the past 35-40 ka have been reported from the entire Himalayan belt (Cronin, 1982;Burbank and Fort, 1985;Shroder et al., 1986;Valdya, 1988;Cronin, 1989;Fort et al., 1989;Shroder et al., 1993;Sangode and Bagati, 1995;Kotlia et al., 1998;Valdiay, 2001;Phartiyal et al., 2005;Phartiyal and Sharma, 2009;Bali et al., 2003;. ...
Morphometry is a quantitative approach of analysing linear, areal and relief parameters to understand the role of neotectonic activity in geomorphologic evolution of a river basin. In the present study multidisciplinary integrated approach using morphometric parameters along with remote sensing and GIS technique have been applied for determining the quantitative parameters indicative of neotectonic activity in the Parvati basin, Higher Himalaya. The lineament pattern observed in the basin shows major trend in NE-SW followed by NW-SE and NNE-SSW directions. The basin is a 6 th order drainage basin with dominating dendratic-trellis drainage pattern having very strong structural/tectonic control and is in its late youth stage of geomorphic development. Parvati basin shows coarse drainage density with fine texture suggesting more surface runoff and less infiltration in the area. The basin is highly elongated in shape tapering towards the southwest with high susceptibility to erosion with lower peak flow for longer duration. The above observations clearly indicate a tectonic and lithological control over the evolution of drainage pattern of Parvati basin.
... Malik et al (2014) used IRS-1D LISS-III images along with Shuttle Radar Topography Mission (SRTM) DEM to highlight landscape features and drainage anomalies related to active faults along the foothills of Kumaun Sub-Himalaya. Philip (2007), Philip et al. (2011Philip et al. ( , 2012Philip et al. ( , 2014Philip et al. ( , 2017 exploited the advantage of medium to high-resolution multispectral and panchromatic satellite images from IRS-1C/1D and their follow-on missions for neotectonics and paleoseismicity studies. They identified active faults at several locations such as in Kangra valley, Pinjaur Doon, Kala Amb areas of the Northwestern Himalaya. ...
Satellite-based remote sensing is being used by geologists for the last five decades for conducting geological surveys and applications. The launch of Indian Remote Sensing Satellite (IRS)-1C in December 1995 opened new opportunities to study and characterise Earth’s surface materials, landforms and surface as well as subsurface processes. The availability of panchromatic (PAN) camera and Wide Field Sensor (WiFS) in addition to multispectral Linear Imaging Self-Scanning sensor-III (LISS-III) made the IRS-1C unique among its contemporary satellites. While wide coverage provided by the WiFS images could be used for studying regional features like geological and geomorphic provinces and mega lineaments/fractures, the PAN-sharpened LISS-III images facilitated improved interpretability and made large-scale (up to 1:10,000) mapping possible. In this article, we review the geological applications of the IRS-1C and its follow-on missions carrying similar sensors, with an aim to present the status of the achievements made with this unique mission. From the basic geological and geomorphological mapping to different applied geological investigations in the fields of hydrogeology, mineral and hydrocarbon exploration, geoengineering surveys, geoenvironmental appraisal of engineering, mining and infrastructural projects, and geological hazards are covered in this review. While reviewing different applications, we highlight major projects executed, new initiatives undertaken, and scientific findings through the use of IRS-1C data and its successor missions. We also provide some recommendations on the future requirements of remote sensing systems and processes from the geological perspective.
... The HFT is the youngest active thrust separating the Himalayan region and the Indo-Gangetic alluvial plain [Kumar et al., 2009]. The HFT, the MBT and the MCT so far have generated numerous major EQs in this region [Philip et al., 2014]. Other tectonic features include the Jhelum Balakot fault, the Drang thrust, the Lesser Himalayan Crystalline Nappes, the Jammu thrust, the Vaikrita thrust, the Karakoram fault, the Jwala Mukhi thrust, and the Ramgarh thrust. ...
North-west Himalayas and its adjoining regions have been experiencing deadly earthqaukes from time to time and are home for a large portion of population of Indian subcontinent. Knowledge of regional path attenuation and site parameters are prerequisite while attempting seismic hazard studies towards minimizing damages during future earthqaukes for a region. Present work focuses on the determination of path attenuation and site characteristics of earthqaukes recording stations, located in the north-west Himalayas and its adjoining regions, within India. It is done using two- step generalized inversion technique. In the first step of inversion, non-parametric attenuation curves are developed by constraining attenuation to be a smooth decaying function with hypocentral distance. Qs = (105 ± 11)f (0.94 ± 0.08) as S wave quality factor is obtained indicating that the region is seismically active having high degree of heterogeneities in the crustal medium. In the second step of generalized inversion, site amplification curve, at each recording station, is computed as the ratio of site spectral amplitude of horizontal and vertical components. In addition, based on Horizontal to vertical spectral ratio (HVSR) method, predominant frequency of each recording station is calculated. Values of predominant frequencies based on HVSR and generalized inversion are found matching for each of the recording station. Based on obtained predominant frequency, site class of 101 recording stations, which at present are absent, are determined in this work. Determined path attenuation as well as site parameters can be collectively used for developing regional ground motion models and subsequently for seismic hazard studies for the selected region.
... The HFT is the youngest active thrust separating the Himalayan region and the Indo-Gangetic alluvial plain [Kumar et al., 2009]. The HFT, the MBT and the MCT so far have generated numerous major EQs in this region [Philip et al., 2014]. Other tectonic features include the Jhelum Balakot fault, the Drang thrust, the Lesser Himalayan Crystalline Nappes, the Jammu thrust, the Vaikrita thrust, the Karakoram fault, the Jwala Mukhi thrust, and the Ramgarh thrust. ...
