Bal Krishna Rastogi

Institute of Seismological Research | ISR · Seismology

The Himalayas are facing the maximum number of natural disasters like earthquakes, landslides and floods. The young age of the mountains, active continent–continent collision tectonics and geographical position are all contributory factors. The levels of different hazards in the Himalayas are identified in this chapter.

Some new insights about the structure and seismotectonics of the Himalaya are given in this chapter including thick or doubling of the crust and the role of detachment surface, Low-Velocity Zones (LVZs), transverse faults and subducting ridges of the Indian plate in Himalayan earthquakes. Strain rates inferred from GPS are described for different s...

The Gorkha, Nepal earthquake of April 25, 2015 (occurring on a Saturday morning) affected 8 million people of Kathmandu and nearby districts which urgently needed all kinds of relief materials like food, water, medicines, shelter, and sanitary facilities. Nearly 9000 people died and 23,000 injured. A short summary of search, rescue, and relief oper...

In this chapter, geology, seismotectonics and geodetic deformation of Nepal is described in short. Geology of the Kathmandu Valley is also covered. Major thrusts and rock formations are shown in maps. Importance of the Main Himalayan Thrust (MHT) being the seat of large earthquakes is reiterated. Past Significant Earthquakes in Himalaya and especia...

After any large earthquake, people are scared of aftershocks and wish to know that how long the aftershocks may continue and what could be the maximum magnitude. The behavior may be somewhat different in different regions; hence, it is important to study the same for the Gorkha Nepal earthquake. Generally, it has been observed that the largest afte...

Geotechnical and other engineering aspects of the 2015 Nepal Earthquake have been investigated by various workers (Aydan and Ulusay 2015, Bhagat et al. 2017, Goda et al. 2015, Parameswaran et al. 2015, Pokhrel et al. 2015a, b, Wijeyewickrema et al. 2015). Some important observations are summarized here.

This chapter gives seismic parameters of Mw 7.8 April 25, 2015 Gorkha, Nepal earthquake. The salient aspects of tectonics, slip modeling, geodetic deformation, rupture process, aftershocks, strong ground motion and damage caused are highlighted. Nepal has varied topography from low lands (EL 60 m) in the south to high mountains in the north includi...

Information about damage caused by the large earthquake of April 25 (Mw 7.8) and its major aftershock of May 12 (Mw 7.3), 2015 that struck Nepal is compiled. The earthquakes caused about 8964 human deaths (8,857 in Nepal, 79 in India, 27 in Tibet, China, and 4 in Bangladesh). It has caused 22,300 injuries and full or partial damage to 756,000 build...

The Saurashtra Horst, south of the Kachchh Rift Basin, is a significant tectonic block in the northwestern Deccan Volcanic Province of India. The Saurashtra Horst belongs to the stable continental region and typically experiences shallow intraplate earthquakes with depths up to 20 km. We analysed spectra of P- and S-waves using 182 broadband seismo...

Geotechnical, geological and geophysical investigations for seismic microzonation and site-specific earthquake hazard analysis adopted in Gujarat, western India, are explained. Geology of the area is studied to understand basic earthquake hazards. Seismicity and tectonics are studied up to 50 km distance in detail and 300 km distance in general. To...

This study estimates the consequences of a scenario earthquake to a city or region using the formulated mathematical model based on multi-criteria decision-making methods like Simple Additive Weighting (SAW) and Weighted Product Method (WPM). A customized tool was developed using MATLAB to calculate, map and display the damage scenarios correspondi...

Ahmedabad, the most populous city of Gujarat, assigned zone III in the seismic zone map of India (BIS 2002), has experienced moderate earthquakes in the past. Several high-rise buildings were collapsed or severely damaged in the city during 2001 Bhuj earthquake (Mw 7.6), which was 240 km from the city. Keeping this in view, micro-level seismic haza...

Cambay basin is one of the major onshore oil-bearing sedimentary basins of India situated at its western margin in Gujarat state. The region is seismically active and experiences three devastating earthquakes in the past. The region comes under the seismic zone IV and V and necessitates the extensive geophysical studies in for subsurface characteri...

Magnetotelluric (MT) data have been acquired at 40 locations in Tuwa and its surrounding region (200 km east of Ahmedabad and 15 km north–northwest of Godhra) in the Mainland Gujarat with an average station spacing of 1.5 km. MT impedance tensors have been estimated in the period range of 0.001–100 s. The data have been modeled using non-linear con...

The epicentral region of the 26 January 2001 Bhuj earthquake (7.7 Mw) in the Kutch region of India has been experiencing a vigorous and unique intraplate aftershock activity, which shows a V-shaped pattern and N/NE migration along the western margin of the Wagad uplift located to the northeast of the mainshock. This study presents 3D resistivity st...

Several unusual strong earthquakes occurred in central India along the Narmada-Son Lineament (NSL) zone, far from active plate boundaries. To understand the role of collisional processes in the origin of this seismicity, we develop a numerical thermomechanical model of shortening between the Indian Plate and Asia. We show that at the final stage of...

Liquefaction is one of the most destructive secondary effects caused by large earthquakes, which is most common in saturated soil deposits. In the present study, liquefaction potentials of soils in the southern part of Ahmedabad district of Gujarat state in western India are determined and a liquefaction potential map is prepared. For preparing thi...

The empirical factor Kappa (κ), governs the rapid decay of spectral amplitude at high frequencies. It is one of the important parameters required in the simulations of earthquake strong ground motions. The present study estimates κ for 16 sites of Kachchh region of Gujarat (India). The Kachchh region is one of the most seismically active intraplate...

Ahmedabad city falls in Zone III of the seismic zoning map of India (BIS) where earthquake of maximum magnitude 6.0 can be expected. The Ahmedabad city is going to be a mega city in future and the possibility of high rise structures cannot be ruled out. Therefore, strong motion parameters are estimated (at the surface) for earthquake resistant desi...

Gandhinagar City (the Capital of Gujarat, India) falls under Zone III on the seismic zoning map of India where an earthquake of magnitude 6 can be expected. It is a well established fact that the site amplification/ shaking and damage is large in soil covered areas. To estimate the effect of soil on ground motion and to estimate the strong ground m...

The continued reservoir-triggered seismicity for five decades in Koyna area has been attributed to southward migration of seismicity (during 1967–1992 near and south of Koyna dam and from 1993 onwards mostly near the new Warna reservoir). Spread of seismicity in the vicinity of reservoirs is attributed to pore-pressure diffusion. Moderate size Koyn...

The Kachchh rift basin is located on the western continental margin of India and has a history of experiencing large to moderate intraplate earthquakes with M ≥ 5. During the past two centuries, two large earthquakes of Mw 7.8 (1819) and Mw 7.7 (2001) have occurred in the Kachchh region, the latter with an epicenter near Bhuj. The aftershock activi...

The alluvial successions in the northern Gujarat alluvial plain (western India) have been investigated for reconstructing the climatic fluctuations during the last 40 ka. Alluvial architecture and geochemical proxies indicate prevalence of a strengthened Indian SummerMonsoon (ISM)with fluctuations between the late Marine Isotopic Stage 3 (MIS 3; 37...

The dryland fluvial sequences exposed in the lower part of the Gujarat alluvial plain are investigated for palaeohydrological/palaeoclimatic reconstruction using conventional sedimentology, grain size analyses supported by optical chronology. Considering that the study area is cradling large-scale constructional activities, an attempt has also been...

In the present study, a set of correlation relations between standard penetrations tests (SPT-N values) and shear wave velocity (Vs) for different categories of soils is developed for Dholera region, Gujarat state, Western India. Shear wave velocities were measured using multichannel analysis of surface wave (MASW at 42 sites) and by PS logging (at...

ABSTRACT Geotechnical investigations of soil consisting of surface and subsurface studies are performed in the southern part of Ahmedabad district in Gujarat state of western India. Surface investigations include detailed geological and geomorphological mapping, whereas subsurface investigations involved selected drilling, soil sampling and laborat...

ABSTRACT Estimation of liquefaction resistance, also called Cyclic Resistance Ratio (CRR) of soil, is an important aspect of geotechnical earthquake engineering; it is one of the most important secondary effects of earthquake which causes severe damages to engineering structures. The liquefaction potential is estimated in terms of factor of safety...

The Cambay graben is one of the known geothermal provinces in the Gujarat state in Western India. Temperatures between 100 and 150 °C have been recorded up to 3.5 km depth in this zone. To understand the geoelectric structure and possible source zone of hot water spring at Chabsar, 50 km southwest of Ahmedabad, on the left bank of Cambay basin, mag...

Seven boreholes are drilled in the coastal region of Gujarat; three in Kachchh (at Jangi, Mandvi and Mundra), one in Saurashtra (Jodiya) and three in mainland Gujarat(Dahej, Kamboi and Dholera) to depth of 27–80 m for estimating the surface strong ground motion parameters. These parameters are required for seismic resistant design of structures in...

We estimated ground motions at 12 selected sites in the Kachchh rift basin of Gujarat in the western peninsular shield area of India, where the damaging 1956 Anjar earthquake (Mw 6.0) was experienced. The ground motions are estimated by applying the empirical Green’s function approach using an earthquake of Mw 4.5, which occurred on the inferred ru...

Dryland rivers, dominated by short-lived, localised and highly variable flow due to discrete precipitation events, have characteristic preservation potential, which serves as suitable archives towards understanding the climate–tectonic coupling. In the present study, we have investigated the fluvial records of a major, southerly-draining river – th...

Recent seismological research in India can be mainly grouped into study of 1) seismogenesis and seismotectonics of the three regions viz., Himalaya, Andaman-Nicobar subduction zone and the Stable Continental region (SCR); 2) Strong motion study and 3) earthquake prediction. Last few years have witnessed significant change in monitoring of earthquak...

The landscape of Kachchh is a unique example of active intraplate region in the world. Various structural features such as domes, faults, folds and associated intrusive suggest early tertiary tectonic history, while youthful topography like youthful nature of the fault scarps and gorges suggests Quaternary tectonic history. Kachchh Mainland Fault (...

Presence of large boulders along rocky coasts can be used as archives to reconstruct past extreme wave event history, vital for the coastal hazard assessment. Dimensions of boulders lying in supratidal zone have been used to reconstruct the origin of wave responsible for their transport and processes. There are several mathematical equations availa...

Temporal pattern of global seismicity indicates temporal clustering of large earthquakes (Mw≥8.2) followed by relative quiescence (stress shadow). It is a characteristic seismic pattern along the plate boundaries. Clustering of the largest earthquakes during 1950s to 1960s followed by the extended period of low-moment release until 2003 and then ag...

Fluvial terrace formation is often regulated by external forcings like climate, tectonic and eustatic changes. These terraces, particularly in a dryland environment, preserves the discrete signatures of these external forcings, thus enabling us to reconstruct the fluvial response to the late Quaternary palaeoenvironmental changes and factors govern...

Abstract: Kachchh is one of the most seismically active intraplate regions in the world, which has produced several major earthquakes in historical period. Katrol Hill Fault (KHF) is one of the active faults of Kachchh. The Southern Kachchh Mainland is delimited by KHF in north and Gulf of Kachchh in south. Several studies have revealed the geomorp...

A reliable and comprehensive characterization of expected seismic ground shaking is essential to improve building codes, particularly for the protection of critical infrastructures and for land use planning. So far, one of the major problems in classical methods for seismic hazard assessment consisted in the adequate characterization of the attenua...

We map secondary surface deformation from the 2001 Mw7.7 Bhuj earthquake in western India near the surface trace of the Bharudia Fault (BhF)/North Wagad Fault (NWF) north of Bharudia, about 22 km north from the 2001 main shock epicenter, with the help of ASTER satellite data followed by ground checks. Important active deformational geomorphic featu...

Abstract In present study the results of integrated studies of landform development and geomorphic indices of drainage networks across the South Wagad Fault (SWF) zone have been presented. The SWF is a structure that is morphogenic in nature, creating a 40-m-high E-W trending escarpment that extends ~ 80 km at the southern end of the Wagad uplift....

This paper purports the temporal and spatial variations of total electron content (TEC), outgoing longwave radiation (OLR) and sea surface temperature during the greater earthquake regime. Nighttime TEC variations have been observed to be lower than those of the daytime. They were in the range of 10–30 TECU (µ = 16 TECU) over nighttime, whereas 12–...

The northwestern Deccan Volcanic Province of India and its pericratonic rift basins were reactivated during different stages after the breakup of India from the Gondwanaland and collision with the Asian plate. In this study, we present results of crustal thickness and average crustal Vp/Vs ratios beneath this plume-affected region using common conv...

The morphometric analysis using geostatistical information of various landforms has proved useful in delineating areas of active deformation. Here we present the study of five drainage basins, namely Saraswati, Heran, Devka, Megal and Noli flowing into the Arabian Sea on Kathiawar peninsula, now called Saurashtra using quantitative geomorphologic a...

The Gravity and Magnetic surveys were conducted in 5 blocks of Cambay basin in Gujarat at an interval of 1 km (approx) to map the basement configuration. Total 750 Gravity and Magnetic stations are covered in grid pattern. Bouguer gravity map is prepared at an interval of 1 mgal interval for better resolution of different features of the basin.

The coastal segment of Diu Island from west coast of India has been studied for its boulder deposits. The dimensions, morphology and characteristics of these boulders were studied to elucidate the type of wave responsible for their detachment from jointed shore platform and transport them to their present final position. The generated data were com...

Some earthquakes to Mw5 level are occurring along two faults viz. Kachchh Mainland Fault and South Wagad Fault near the epicenter of Mw7.7 Bhuj earthquake of 2001. These faults are not the causative fault of the 2001 earthquake and suspect for future large earthquake. In absence of detail geophysical surveys, the sub-surface orientation of these fa...

Dry land fluvial system in western India emanates from the Aravalli ranges and drains into the Gulf of Cambay and the Gulf of Kachchh. The sedimentary characteristics and textural attributes of the incised alluvial sequences in various river basins of western Indian indicate significant variability in the palaeohydrological conditions. Considering...

Lighthouses are the road signs of the ocean. They guide sailors through dangerous waters. Each lighthouse design is based on the land it is built on, its purpose, and the technology available. The Geometry of the towers can be round, square, octagonal, or conical in shape. These towers need to be in operation 24x7, guiding the ships coming towards...

The Kutch region of Gujarat in India is the locale of one of the most devastating earthquake of magnitude (M w) 7.7, which occurred on January 26, 2001. Though, the region is considered as seismically active region, very few strong motion records are available in this region. First part of this paper uses available data of strong motion earthquakes...

The scaling relationships for stress drop and corner frequency with respect to magnitude have been worked out using 159 accelerograms from 34 small earthquakes (M (w) 3.3-4.9) in the Kachchh region of Gujarat. The 318 spectra of P and S waves have been analyzed for this purpose. The average ratio of P- to S-wave corner frequency is found to be 1.19...

The present study purports the analysis of total electron content (TEC, which is one of the major ionosphere anomalies during the earthquake), sea surface temperature (SST) and outgoing long-wave radiation (OLR) during the earthquake event recorded on 10 March 2013 (M = 6.5). Global assimilative ionosphere modelled output TEC values have been used...

Ports are lifeline systems that function as a storage and maintenance facilities for the transport of cargos and people via water. The port structures are frequently exposed to failure under severe seismic loading. It was not only observed during 1995 Kobe earthquake but also during 1989 Loma Prieta and 1999 Kocaeli earthquakes. The scenario is mor...

The tectonically active Kachchh peninsula in western India lies in the southwest monsoon trajectory and hence provides a rare opportunity to decipher the temporal changes in climate–tectonics interaction in the evolution of the fluvial landforms. Reconstructions based on geomorphology, sedimentology, and geochemistry supported by optical chronology...

Abstract The three-dimensional spatial distribution of relative scattering coefficients is estimated in the Kachchh region, western India, by means of an inversion technique applied to coda wave envelopes. Data used consisted of selected vertical-component, broad band recordings from 438 earthquakes with moment magnitudes M ranging from 1.6 to 4.2...

The pipeline systems are commonly used to transport water, sewage, oil, natural gas and other materials world over. Thes pipelines run over long distances and in some instances they cross high seismic areas including fault crossings. Many buried pipelines in India run through high seismic areas and are exposed to considerable seismic risk. These pi...

The present work reviews the strong motion studies done in Gujarat State of western India. Prior to the 2001 Bhuj earthquake, no strong motion instrument was in operation in Gujarat. After the earthquake, number of research institutes/universities from India and abroad deployed strong motion instruments to study aftershock activity, source dynamics...

Lighthouses are the road signs of the ocean. They guide sailors through dangerous waters. Each lighthouse design is based on the land it is built on, its purpose, and the technology available. The Geometry of the towers can be round, square, octagonal, or conical in shape. These towers need to be in operation 24x7, guiding the ships coming towards...

Jetties are one of the most important structures in coastal facilities, which can be used for transporting large quantities of goods and raw materials from one place to other. Their functionality is very much essential because they are lifeline structures of the country. Damaged and unserviceable port structures cause delay of export and import bus...

Pipelines have been acknowledged as the most reliable, economic and efficient means for the transportation of water and other commercial fluids such as oil and gas. They are often referred to as “lifelines”, since they carry materials essential to the support of life and maintenance of property. The earthquake safety of buried pipelines has attract...

Ports are lifeline systems that function as a storage and maintenance facilities for the transport of cargos and people via water. The port structures are frequently exposed to failure under severe seismic loading. It was not only observed during 1995 Kobe earthquake but also during 1989 Loma Prieta and 1999 Kocaeli earthquakes. The scenario is mor...

Ports are lifeline systems that function as storage and maintenance facilities for the transport of cargos. The port structures are frequently exposed to failure under severe seismic loading, for example, 1995 Kobe, 1989 Loma prieta, 1999 Kocaeli and 2001 Bhuj earthquakes. The scenario is more critical if the port sites are located within the seism...

The 2001 Bhuj earthquake (Mw 7.6) source zone is examined in the light of crack density (ε), saturation rate (ξ) and porosity parameter (ψ) using new data set derived from a large aftershock sequence recorded by the Gujarat seismic network (GSNet) during November, 2006 - December, 2009. Processes of rupture initiations of the mainshock and its afte...