This file was created by the TYPO3 extension publications --- Timezone: CEST Creation date: 2026-06-03 Creation time: 23:00:29 --- Number of references 36 article Roy2025748 Article 2025 10.17491/jgsi/2025/174154 Journal of the Geological Society of India 101 748 – 753 6 https://www.scopus.com/inward/record.uri?eid=2-s2.0-105007990207&doi=10.17491%2fjgsi%2f2025%2f174154&partnerID=40&md5=59e91e742fdc48ce12eab9f38bd5b846 Cited by: 0 Sukanta Roy Deepjyoti Goswami Vyasulu V. Akkiraju Anup K. Sutar Sunil Rohilla C.S. Vishnu Himanshu Chaube article Akkiraju2025 Article 2025 10.1016/j.ijrmms.2025.106273 International Journal of Rock Mechanics and Mining Sciences 195 https://www.scopus.com/inward/record.uri?eid=2-s2.0-105016784376&doi=10.1016%2fj.ijrmms.2025.106273&partnerID=40&md5=c57f547680bca72962aa1c52a7694237 Cited by: 0 Vyasulu V. Akkiraju Deepjyoti Goswami Jochem Kueck Gerd Klee Brijesh K. Bansal Sukanta Roy article WOS:000927333300001 2023 10.1016/j.tecto.2023.229725 TECTONOPHYSICS 848 Fault zone; Downhole geophysical logs; Recurrent earthquakes; Scientific drilling; Koyna; India Nagaraju Podugu Deepjyoti Goswami Vyasulu V. Akkiraju Sukanta Roy article Gupta2022619 Abstract: Under certain suitable geological conditions, anthropogenic seismicity due to gold/coal mining, geothermal and natural gas/oil production, filling of artificial water reservoirs, and high-pressure fluid injection has been reported globally. The reservoir-triggered seismicity (RTS) is most prominent, having been reported from hundreds of with at least five sites where earthquakes exceeding M 6 occurred, claiming human lives and destruction of properties. The most important correlate for RTS to occur is the height of water column in the reservoir. Certain common characteristics of the RTS sequences have been identified, which discriminate them from normal earthquake sequences. Factors influencing RTS include the highest water levels reached in the reservoir, duration of the retention of high-water levels and rate of loading/unloading. The mechanism of RTS is reviewed. The absence of knowledge of physical properties of rocks and fluids in the fault zone does not permit us to comprehend the RTS mechanism. Koyna, India, is found to be a very suitable site for such investigations as the earthquakes have been occurring in a small region of 20 × 30 km, at shallow depths (mostly within 8 km), with no other seismic source in the vicinity, and the region being accessible for all kinds of observation and investigations. The suitability of Koyna for setting up of a deep borehole laboratory was discussed during International Continental Drilling Program (ICDP) workshop in 2011 and accepted. Suggestions were made for some additional scientific works, which were completed during 2011–2014. The second ICDP workshop in 2014 approved of going ahead. A 3-km-deep Pilot Borehole has been completed in the vicinity of Donachiwada fault that hosted the main 10 December 1967 M 6.3 earthquake and several earthquakes of M ~ 5. The investigations being carried out are providing the necessary input to set up the proposed ~ 7-km-deep borehole laboratory. In this article, an overview of RTS globally and at Koyna, India, specifically is focused. Article Highlights: Global review of the reservoir-triggered seismicity (RTS) sitesFactors influencing RTS, their common characteristics and mechanismContinued seismicity at Koyna, India, and near-field studies © 2021, The Author(s), under exclusive licence to Springer Nature B.V. 2022 English 01693298 10.1007/s10712-021-09675-z Surveys in Geophysics 43 Springer Science and Business Media B.V. 619-659 CSIR, National Geophysical Research Institute, Hyderabad, 500007, India 2 Boreholes; Diffusion in liquids; Earthquakes; Faulting; Induced Seismicity; Petroleum reservoir engineering; Pore pressure; Stresses, Anthropogenics; Artificial water; Coal-mining; Deep boreholes; Drilling projects; Geological conditions; High water; Permeability; Reservoir-triggered seismicity; Water reservoir level, Abstracting, diffusion; earthquake magnitude; environmental stress; fault zone; permeability; pore pressure; seismicity, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85123101146&doi=10.1007%2fs10712-021-09675-z&partnerID=40&md5=e67f2e15a8351969a235fe9cf8598d47 cited By 3 H.K. Gupta article Gupta2022 Abstract: Anthropogenic activities such as gold and coal mining, oil and gas production, filling of artificial water reservoirs, harnessing of geothermal energy, etc., have induced/triggered earthquakes. Koyna dam, located in the Deccan volcanic province of India, was impounded in 1962, and soon after tremors were reported from the vicinity of Koyna dam. The largest triggered earthquake of magnitude (M) 6.3 occurred on 10 December 1967. The triggered earthquakes have continued until now and the region has experienced 22 events of an M~5, over 200 events of an M~4 and several thousand smaller events. The reservoir-triggered seismicity has continued until 2021, which is unique. Some of the early investigations, leading to drilling of a 3 km deep pilot borehole at Koyna for near-field studies of earthquakes, and a few recent results are summarised in this paper. Research highlights: Koyna, located near the west coast of India, in the Deccan volcanic province is one of the most prominent sites of artificial water reservoir-triggered seismicity (RTS). Triggered earthquakes started soon after the impoundment of Shivaji Sagar lake created by Koyna dam in 1962 and have continued until now.Unlike other RTS sites where triggered earthquakes did not continue for long, Koyna is still active, and it is estimated that RTS may continue for another one to two decades.Detailed field work and analyses of earthquake data demonstrated that Koyna is a very suitable site for near-field studies of earthquakes: an observation that is much needed to validate earthquake genesis models.International Continental Drilling Programme sponsored workshops and participation of experts from all over the world helped in deciding to dig a 3 km deep pilot borehole. The borehole was completed in June 2017.Recent research studies further demonstrated that the Koyna region is under critical stress.Studies under progress would help in designing the proposed ~7 km deep borehole laboratory. © 2022, Indian Academy of Sciences. 2022 English 23474327 10.1007/s12040-021-01780-2 Journal of Earth System Science 131 Springer CSIR-National Geophysical Research Institute, Telangana, Hyderabad, 500 007, India 1 borehole geophysics; earthquake event; human activity; laboratory method; reservoir; seismicity, India; Koyna Dam; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85121444731&doi=10.1007%2fs12040-021-01780-2&partnerID=40&md5=a952c8bcbef0a06be8b25abd8c1a87ac cited By 1 H.K. Gupta article Gupta20211415 Article 2021 Current Science 120 1415 – 1416 9 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85108144301&partnerID=40&md5=75db57dad07a42bc91b8d966971ea6fa Cited by: 3 Harsh K. Gupta article Gupta20211556 Anthropogenic seismicity has been observed due to filling of artificial water reservoirs, geothermal and natural oil/gas production, and gold/coal mining under favorable geological conditions. Among these, artificial water reservoir triggered seismicity (RTS) is most prominent, with over 200 sites globally where RTS has been observed, including 5 sites where earthquakes exceeding M 6 magnitude occurred. Koyna, located near the west coast of India in stable Deccan Volcanic Province is the most prominent site where the largest RTS event of M 6.3 occurred in 1967, and the RTS has continued till now, for near field study of earthquakes. Here we present a summary of (a) global RTS, (b) scientific work carried in the Koyna region, (c) characterizing RTS, and (d) establishing a 3 km deep Pilot Borehole laboratory as a precursor to setting up of a ∼ 7 km deep bore hole laboratory. The work being carried out is providing necessary inputs for the design of the ∼ 7 km deep borehole laboratory for the near field studies of RTS and shed light on the geneses of earthquakes in general and RTS. © 2021, GEOL. SOC. INDIA. 2021 English 00167622 10.1007/s12594-021-1913-x Journal of the Geological Society of India 97 Springer 1556-1564 CSIR-National Geophysical Research Institute, Hyderabad, 500 007, India 12 earthquake magnitude; earthquake trigger; geothermal energy; geothermal power; hydrocarbon reservoir; seismicity, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85121464911&doi=10.1007%2fs12594-021-1913-x&partnerID=40&md5=f539c7dd344fb2826c34a5dcd310e6f0 cited By 0 H.K. Gupta article Gupta2020 2020 English 13884360 10.1007/978-3-030-10475-7_15-1 Encyclopedia of Earth Sciences Series PartF4 Springer Science and Business Media B.V. National Geophysical Research Institute, Council of Scientific & Industrial Research, Hyderabad, India https://www.scopus.com/inward/record.uri?eid=2-s2.0-85133329403&doi=10.1007%2f978-3-030-10475-7_15-1&partnerID=40&md5=9a5f8cc0fcc94784899eacfd9dbaf0f3 cited By 0 H. Gupta article Goswami2020 Knowledge of the in situ stress regime is critical to investigate the genesis of recurrent triggered seismicity over the past five decades in the Koyna seismogenic zone. Orientations of in situ horizontal stresses are determined for the first time from analyses of image logs in a 3 km deep scientific borehole KFD1 in the area. KFD1 passed through 1,247 m thick Deccan Traps and continued 1,767 m in the granitic basement. Stress-induced wellbore failures, breakouts and drilling-induced tensile fractures, are identified in the acoustic and microresistivity images of the granitic basement. Additionally, tightly constrained focal mechanisms of 50 earthquakes of M ≥ 3.6, reported in literature, are inverted to constrain the stress regime. Salient results are as follows: (i) wellbore breakouts and drilling-induced tensile fractures constrain N9°W ± 17° orientation for maximum horizontal principal stress (SHmax); (ii) consistency with the regional NNW-SSE orientation of SHmax from inversion of earthquake focal mechanisms shows that the borehole data are representative for the Koyna region; (iii) breakout rotations at multiple depths below 2,100 m indicate that the borehole may have passed through localized fault damage zones; (iv) consistent strike azimuths of steeply dipping fractures with SHmax orientation indicate favorable conditions for strike-slip to normal transitional faulting environment; and (v) stress inversion of 50 well-determined earthquake focal mechanisms supports transitional faulting environment in the Koyna seismogenic zone. Thus, stress orientation and fracture information from borehole data, together with stress regime constrained from inversion of earthquake focal mechanisms, shed new light on the faulting environment in the region. ©2020. American Geophysical Union. All Rights Reserved. 2020 English 02787407 10.1029/2019TC005647 Tectonics 39 Blackwell Publishing Ltd Ministry of Earth Sciences, Borehole Geophysics Research Laboratory, Karad, India; Now at CSIR-National Geophysical Research Institute, Hyderabad, India 1 Boreholes; Buildings; Earthquakes; Fracture; Horizontal wells; Infill drilling; Oil field equipment; Seismographs; Stresses; Strike-slip faults; Well logging, Borehole breakouts; Drilling-induced tensile fractures; Principal stress; Seismogenic zones; Stress orientations; Stress rotation, Fault slips, borehole breakout; borehole logging; Deccan Traps; drilling; faulting; focal mechanism; fracture; in situ stress; induced response; seismicity, India https://www.scopus.com/inward/record.uri?eid=2-s2.0-85078501819&doi=10.1029%2f2019TC005647&partnerID=40&md5=bdd15b250e33a85266e4b2ac083a83bd cited By 12 D. Goswami P. Hazarika S. Roy article Das20201097 Koyna region in western India experienced more than 1,00,000 earthquakes of different magnitudes (M ~ 1.0–6.3) in the past five decades. Earthquakes in this region are believed to be triggered by a change in fluid pressure due to the percolation of the reservoir (Koyna and Warna reservoir) water into the subsurface. A drilling program was set up by the Ministry of Earth Sciences, India and International Continental Scientific Drilling Program (ICDP) to study the deep subsurface lithology, structure, thermal attributes, etc. as the area is covered by ~ 950 m of thick Deccan basalts. This paper reviews all the hypotheses proposed by earlier workers to explain the mechanism of reservoir trigger causing earthquakes and summarizes such theories to a simple generic model. Slip tendency analysis was further carried out based on the proposed model to explain the dependence of fault slip on fault geometry, rock mechanical properties, stress and fluid gradients. Finally, faults at various depths were characterized (favourably oriented, unfavourably oriented and severely misoriented) based on their potential to go into failure. © 2020, Institute of Geophysics, Polish Academy of Sciences & Polish Academy of Sciences. 2020 English 18956572 10.1007/s11600-020-00457-6 Acta Geophysica 68 Springer 1097-1112 Indian Institute of Science Education and Research, Bhopal, MP 462066, India 4 Earthquakes; Infill drilling; Lithology; Reservoirs (water); Solvents, Continental scientific drillings; Fault geometry; Fluid pressures; Generic modeling; Subsurface lithology; Tendency analysis, Fault slips, decadal variation; earthquake event; earthquake magnitude; fault geometry; fault slip; literature review; rock mechanics; seismicity, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85087569434&doi=10.1007%2fs11600-020-00457-6&partnerID=40&md5=e2825c942f3415db5794b51284d7cfa0 cited By 5 D. Das J. Mallik article Gupta2019469 The Koyna earthquake of M 6.3 on December 10, 1967 is the largest artificial water reservoir triggered earthquake globally. It claimed ∼ 200 human lives and devastated the Koyna township. Before the impoundment of the Shivaji Sagar Lake created by the Koyna Dam, there were no earthquakes reported from the region. Initially a few stations were operated in the region by the CentralWater and Power Research Station (CWPRS). The seismic station network grew with time and currently the National Geophysical Research Institute (NGRI), Hyderabad is operating 23 broadband seismographs and 6 bore hole seismic stations. Another reservoir, Warna, was created in 1985, which provided a further impetus to Reservoir Triggered Seismicity (RTS). Every year following the monsoon, water levels rise in the two reservoirs and there is an immediate increase in triggered earthquakes in the vicinity of Koyna-Warna reservoirs in the months of August–September. Peak RTS is observed in September and later during December.Another spurt in triggered earthquakes is observed during the draining of the reservoirs in the months of April- May. A comparative study of RTS earthquake sequences and the ones occurring in nearby regions made it possible to identify four common characteristics of RTS sequences that discriminate them from normal earthquake sequences. As the RTS events continue to occur at Koyna in a large number in a limited area of 20 km x 30 km, at shallow depths (mostly 2 to 9 km), the region being accessible for all possible observations and there being no other source of earthquakes within 100 km of Koyna Dam, it was suggested to be an ideal site for near field observations of earthquakes. This suggestion was discussed by the global community at an ICDP sponsored workshop held at Hyderabad and Koyna in 2011. There was an unanimous agreement about the suitability of the site for deep scientific drilling; however, a few additional observations/experiments were suggested. These were carried out in the following three years and another ICDP workshop was held in 2014, which totally supported setting up a borehole laboratory for near field investigations at Koyna. Location of a Pilot Bore-hole was decided on the basis of seismic activity and other logistics. The 3 km deep Pilot Borehole was spudded on December 20, 2016 and completed on June 11, 2017. © 2017, Geological Society of India. Review 2019 English 00167622 10.1007/S12594-017-0771-2 Proceedings of the Indian National Science Academy 85 Geological Society of India 469 – 480 CSIR- National Geophysical Research Institute, Hyderabad, 500 007, India 2 comparative study; earthquake event; earthquake trigger; reservoir; reservoir-induced seismicity; seismic discrimination; seismograph; site investigation, India; Koyna Dam; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85087000299&doi=10.1007%2fS12594-017-0771-2&partnerID=40&md5=88389dc8fda8a9a7e6a94a74c90b260a Cited by: 3 Harsh K. Gupta article Dhulipudi2019 Analysis and comparison of geophysical logs from seven exploratory boreholes of 1–1.5 km depth in the Koyna-Warna region of India illustrate variations in physical properties and structural characteristics of the basalts and underlying granite-gneiss basement in and around the seismogenic zone. In the north, south of the Koyna reservoir, densities are higher, gamma values are lower, fractures dip at high angles with low fracture permeabilities. To the south, around the Warna reservoir, densities are lower, gamma values higher, and resistivity values are low. In the southernmost borehole at Khadi, basement is highly fractured, and there are significant amounts of water outflow associated with the fracture system. The fracture density increases to the south, with fracture dips ranging from medium to low angles with permeability values two orders of magnitude higher than in the northern boreholes. These variations in physical and structural properties resulting in a highly heterogeneous crust, reflect the cumulative effect of episodes of tectonic activity over millions of years that this region has undergone. © 2019 Elsevier B.V. 2019 English 00319201 10.1016/j.pepi.2019.106311 Physics of the Earth and Planetary Interiors 296 Elsevier B.V. CSIR-National Geophysical Research Institute, Hyderabad, India Boreholes; Buildings; Exploratory boreholes; Fracture; Geophysics; Reservoirs (water); Structural geology, ATV images; Crustal heterogeneity; Fracture pattern; Geophysical logs; Koyna-Warna, Well logging, assessment method; borehole; fracture propagation; geophysical method; heterogeneity; permeability; tectonic setting, Deccan; India, Ambystoma tigrinum stebbensi virus https://www.scopus.com/inward/record.uri?eid=2-s2.0-85073733125&doi=10.1016%2fj.pepi.2019.106311&partnerID=40&md5=a52d7ce6f98f6cd4346767f2a932fa00 cited By 3 G. Dhulipudi S. Nittala K. Arora S.R. Mannepalli S. K.N.S.S.S S. Yadavally S.V.K. Potharaju S. H.V.S. article Goswami20196101 Delineation of subsurface faults and damage zones is a major goal of scientific drilling projects in seismically active areas. Geophysical logs acquired in a 3-km deep scientific borehole KFD1 in the Koyna seismogenic zone, a site of recurrent reservoir triggered seismicity over the past 55 years, provide an unprecedented opportunity to investigate the rock properties and delineate the fault zones. KFD1 passed through 1,247-m thick Deccan traps and continued for 1,767 m into the underlying granitic basement rocks that host the seismic activity in the depth range 2–10 km. We have studied the physical properties and acoustic behavior of basement granitoids from the analysis of geophysical logs from 1,500 to 3,000 m. Salient results are as follows. (1) Seven anomalous zones are identified below 2,100-m depth based on electrical resistivity, caliper, density, neutron porosity, self-potential, and sonic data. (2) The anomalous zones are characterized by significant shear wave velocity anisotropy (up to 25%), as revealed by cross-dipole sonic data. (3) Dispersion analysis of dipole flexural modes confirms that the anisotropy is primarily stress induced; fast polarized shear wave azimuth (FSA) therefore indicates the orientation of maximum horizontal compressive stress SHmax. (4) Comparison of FSA with independent estimates of SHmax orientations obtained from drilling induced tensile fractures and strike of inclined fractures in the anisotropic zones shows that FSA is controlled mainly by the stress regime. Therefore, the stress rotations inferred from anisotropy analyses in the anomalous zones indicate their association with subsurface fault damage zones. ©2019. American Geophysical Union. All Rights Reserved. 2019 English 21699313 10.1029/2018JB017257 Journal of Geophysical Research: Solid Earth 124 Blackwell Publishing Ltd 6101-6120 Ministry of Earth Sciences, Borehole Geophysics Research Laboratory, Karad, Maharashtra, India 6 acoustic logging; damage; fault zone; granitoid; reservoir-induced seismicity; rock property; seismic anisotropy; seismic zone; sonic boom; stress field; structural control, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85068168197&doi=10.1029%2f2018JB017257&partnerID=40&md5=407fc4287915c4c4522ee84b04e85b93 cited By 14 D. Goswami S. Roy V.V. Akkiraju article Podugu2019 A 3 km deep research borehole KFD1 was drilled in the Koyna reservoir-triggered seismicity region, Western India, between December 2016 and May 2017. The 1967 M 6.3 Koyna earthquake had generated a NNE-SSW trending surface fissure zone in the Nanel-Donichawadi-Kadoli sector. KFD1 is located 5 km south of Kadoli along the trend of the Donichawadi fault zone. Online gas monitoring was carried out during drilling of KFD1 from 1315 m to 2831 m depth to sample and study the composition of crustal gases. Formation gases CO2, CH4, H2, and He were only observed during water flushing of 100 m intervals following coring runs. Laboratory analyses of gas samples collected between 1737 m and 2831 m depth revealed concentrations of up to 1200 ppmv CO2, 186 ppmv CH4, 139 ppmv H2, and 12.8 ppmv He. Zones enriched in gases are mostly below the 2100 m depth with significant He enhancement ranging from 4.6 to 7.6 ppmv above the atmospheric value. The He-rich zones correlate well with the zones of anomalous physical and mechanical properties identified from geophysical logs and are characterized by high fracture density as revealed from borehole images, indicating that the borehole punctured multiple fracture zones. The helium concentrations are consistent with those previously observed over the surface fissures near Kadoli, suggesting a southward extension of the Donichawadi fault zone up to the KFD1 site and confirming that the fault zone is permeable even after 50 years of the 1967 Koyna earthquake.3He/4He ratios of eleven gas samples fall between 0.426±0.022 and 0.912±0.059 Ra, with 4He/20Ne values between 0.3449±0.0091 and 0.751±0.020. Air-corrected helium isotope ratios indicate that helium is a mixture of atmospheric and crustal radiogenic components but no mantle contribution within 2σ analytical uncertainties. © 2019 Nagaraju Podugu et al. 2019 English 14688115 10.1155/2019/1078942 Geofluids 2019 Hindawi Limited Ministry of Earth Sciences, Borehole Geophysics Research Laboratory, Karad, 415 114, India; GFZ German Research Centre for Geosciences, Telegrafenberg, Potsdam, 14473, Germany borehole; carbon dioxide; concentration (composition); drilling; earthquake magnitude; earthquake mechanism; enrichment; fracture zone; gas flow; helium; isotopic composition; isotopic ratio; methane; noble gas; research; reservoir-induced seismicity; source rock, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85072962263&doi=10.1155%2f2019%2f1078942&partnerID=40&md5=f03e1e9f504d7042f22ccc870fc11e56 cited By 10 N. Podugu S. Mishra T. Wiersberg S. Roy article Dutta2018 Scientific deep drilling at Koyna, western India provides a unique opportunity to explore microbial life within deep biosphere hosted by ~65 Myr old Deccan basalt and Archaean granitic basement. Characteristic low organic carbon content, mafic/felsic nature but distinct trend in sulfate and nitrate concentrations demarcates the basaltic and granitic zones as distinct ecological habitats. Quantitative PCR indicates a depth independent distribution of microorganisms predominated by bacteria. Abundance of dsrB and mcrA genes are relatively higher (at least one order of magnitude) in basalt compared to granite. Bacterial communities are dominated by Alpha-, Beta-, Gammaproteobacteria, Actinobacteria and Firmicutes, whereas Euryarchaeota is the major archaeal group. Strong correlation among the abundance of autotrophic and heterotrophic taxa is noted. Bacteria known for nitrite, sulfur and hydrogen oxidation represent the autotrophs. Fermentative, nitrate/sulfate reducing and methane metabolising microorganisms represent the heterotrophs. Lack of shared operational taxonomic units and distinct clustering of major taxa indicate possible community isolation. Shotgun metagenomics corroborate that chemolithoautotrophic assimilation of carbon coupled with fermentation and anaerobic respiration drive this deep biosphere. This first report on the geomicrobiology of the subsurface of Deccan traps provides an unprecedented opportunity to understand microbial composition and function in the terrestrial, igneous rock-hosted, deep biosphere. © 2018, The Author(s). 2018 English 20452322 10.1038/s41598-018-35940-0 Scientific Reports 8 Nature Publishing Group Environmental microbiology and genomics laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India; School of Bioscience, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India; School of Environmental Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India; Ministry of Earth Sciences, Borehole Geophysics Research Laboratory, Karad, 415114, India; CSIR-National Geophysical Research Institute, Hyderabad, 500007, India; Department of Geology and Geophysics, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India 1 RNA 16S, biodiversity; biology; environmental microbiology; genetics; India; metagenome; metagenomics; microbiology; microflora; procedures; sediment, Biodiversity; Computational Biology; Environmental Microbiology; Geologic Sediments; India; Metagenome; Metagenomics; Microbiota; RNA, Ribosomal, 16S https://www.scopus.com/inward/record.uri?eid=2-s2.0-85057525609&doi=10.1038%2fs41598-018-35940-0&partnerID=40&md5=11fd0f12a199be11e4cd9a6f76e22800 cited By 33 A. Dutta S. Dutta Gupta A. Gupta J. Sarkar S. Roy A. Mukherjee P. Sar article Podugu2018120 2018 English 00167622 10.1007/S12594-018-0845-6 Journal of the Geological Society of India 91 Springer 120-124 Borehole Geophysics Research Laboratory (BGRL), Ministry of Earth Sciences,Government of India, India; CSIR-National Geophysical Research Institute, Hyderabad, 500 007, India 1 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85057112245&doi=10.1007%2fS12594-018-0845-6&partnerID=40&md5=aeb9539fc74a9a728fa77433cd2969f2 cited By 7 N. Podugu A. Yadav K. Mallika D. Goswami M.U. Anuradha article Gupta20182907 Reservoir triggered seismicity (RTS) is an anthropogenic effect of creating artificial water reservoirs. Worldwide, the biggest RTS earthquake of magnitude M 6.3 occurred on 10 December 1967 at Koyna, India. From among RTS sites globally, at four sites destructive earthquakes exceeding magnitude 6 occurred. RTS at Koyna has continued until now, whereas at other sites it ceased in a year to a few years. Detailed studies of RTS sequences carried out in 1970s led to delineating common characteristics of RTS events that also help in differentiating RTS sequences from normal earthquake sequences. Association of water level changes in the Koyna and Warna reservoirs and RTS in the Koyna region has been well established. The part played by reservoirs in triggering the earthquakes is not well understood, due to lack of near-field studies. Koyna is found to be a very suitable site for such studies. The suitability of the Koyna site for setting up a deep borehole laboratory and the scientific work to be carried out were discussed in an International Continental Drilling Program (ICDP) supported workshop held in India in 2011. The suggested additional work to be carried out was undertaken from 2011 to 2014 and discussed in the second ICDP Workshop held in 2014. A go-ahead was given for putting up a pilot borehole of 3000-m depth. The pilot borehole drilling started in December 2016 and was completed in June 2017, along with necessary observations and studies. These were presented in the Post Operation Workshop held during October 2017. A few salient features of the work carried out in the last 50 yrs are presented here. © 2018, Seismological Society of America. All rights reserved. 2018 English 00371106 10.1785/0120180019 Bulletin of the Seismological Society of America 108 Seismological Society of America 2907-2918 National Geophysical Research Institute, Uppal Road, Hyderabad, 500007, India 5 Boreholes; Boring; Infill drilling; Reservoirs (water); Water levels, Anthropogenic effects; Artificial water; Borehole drilling; Deep boreholes; Earthquake sequences; Near field study; Salient features; Water level changes, Earthquakes, anthropogenic effect; earthquake magnitude; earthquake trigger; reservoir-induced seismicity; trigger mechanism; water level, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85057109687&doi=10.1785%2f0120180019&partnerID=40&md5=9c1077f5068caebf048d7ae583f482c2 cited By 19 H.K. Gupta article Goswami2017182 Reservoir triggered earthquakes have been occurring in the Koyna area, western India for the past five decades. Triaxial tests carried out on 181 core samples of Archaean granitoids underlying the Deccan Traps provide valuable constraints on rock strength properties in the Koyna seismogenic zone for the first time. The data include measurements on granite gneiss, granite, migmatitic gneiss and mylonitised granite gneiss obtained from boreholes KBH-3, KBH-4A, KBH-5 and KBH-7 located in the western and eastern margins of the seismic zone. Salient results are as follows. (i) Increase of rock strength with increasing confining pressure allow determination of the linearized failure envelopes from which the cohesive strength and angle of internal friction are calculated. (ii) Variable differential stresses at different depths are the manifestations of deformation partitioning in close association of fault zone(s) or localized fracture zones. (iii) Fractures controlled by naturally developed weak planes such as cleavage and fabric directly affect the rock strength properties, but the majority of failure planes developed during triaxial tests is not consistent with the orientations of pre-existing weak planes. The failure planes may, therefore, represent other planes of weakness induced by ongoing seismic activity. (iv) Stress-strain curves confirm that axial deformation is controlled by the varying intensity of pre-existing shear in the granitoids, viz., mylonite, granite gneiss and migmatitic gneiss. (v) Frequent occurrences of low magnitude earthquakes may be attributed to low and variable rock strength of the granitoids, which, in turn, is modified by successive seismic events. © 2017 Elsevier B.V. 2017 English 00401951 10.1016/j.tecto.2017.05.029 Tectonophysics 712-713 Elsevier B.V. 182-192 Borehole Geophysics Research Laboratory, Ministry of Earth Sciences, Karad, 415 114, India; CSIR-National Geophysical Research Institute, Uppal Road, Hyderabad, 500 007, India; CSIR-Central Institute for Mining and Fuel Research, Dhanbad, 826 001, India; Ministry of Earth Sciences, New Delhi, 110 003, India Buildings; Deformation; Granite; Infill drilling; Seismographs; Stress-strain curves, Failure criteria; Granitoids; India; Rock strength; Scientific drilling; Seismic zones, Earthquakes, Archean; basement rock; drilling; failure mechanism; granitoid; rock mechanics; seismic zone; seismicity; strength; stress-strain relationship https://www.scopus.com/inward/record.uri?eid=2-s2.0-85020000079&doi=10.1016%2fj.tecto.2017.05.029&partnerID=40&md5=3a8bd835b17cdc75959292a7f2c8f432 cited By 13 D. Goswami V.V. Akkiraju S. Misra S. Roy S.K. Singh A. Sinha H. Gupta B.K. Bansal S. Nayak article Gupta2017133 Artificial water reservoir triggered earthquakes are now known to have occurred at over 120 sites globally. The part played by the reservoirs in triggering is not exactly known due to lack of near field observations of triggered earthquakes. Koyna, located near the west coast of India, where triggered earthquakes have been occurring since 1962 provides an excellent site for near field observations of the target M ≥ 2 earthquakes. A 6 borehole seismic network has been deployed recently in the Koyna region at depths of 981–1522 m to improve the hypocenter locations. During May–December 2015, a total of 1039 earthquakes of ML ≥ 0.5 were located using the borehole seismic network. The region is also monitored through a dense network of 23 surface broad-band stations. Our analysis indicates a significant improvement in the estimation of absolute locations of earthquakes with errors of the order of ± 300 m, combining both the networks. Based on seismicity, and logistics, a block of 2 × 2 km2 area has been chosen for drilling the first pilot borehole of ~ 3 km depth, where M ≥ 2 earthquakes have been occurring frequently since 2005. © 2016 International Association for Gondwana Research 2017 English 1342937X 10.1016/j.gr.2016.10.014 Gondwana Research 42 Elsevier Inc. 133-139 Council of Scientific and Industrial Research-National Geophysical Research Institute (CSIR-NGRI), Uppal Road, Hyderabad, 500007, India borehole geophysics; borehole logging; broadband data; detection method; drilling; earthquake hypocenter; earthquake magnitude; error analysis; estimation method; reservoir-induced seismicity; site investigation; trigger mechanism, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85009064333&doi=10.1016%2fj.gr.2016.10.014&partnerID=40&md5=0c9cf091fe670d282fdcf56db2c68196 cited By 20 H.K. Gupta D. Shashidhar C.R. Mahato H.V.S. Satyanarayana K. Mallika N.P. Rao B.S. Maity K. Navitha article Sangode2017769 A 1248 m long core (KBH 07, 17°18′07″ N; 73°47′28.2″E, 960m above msl) drilled up to basement in the Deccan traps from Koyna region was sampled at ∼10m interval for magnetic mineralogical studies.Analysis of routine rock magnetic parameters (mass specific magnetic susceptibility: χlf, frequency dependence of susceptibility: χfd, susceptibility of anhysteretic remanance: χARM, saturation isothermal remanance: SIRM, remanance coercivty: B(0)CR, SoftIRM, HardIRM, S-Ratio, SIRM/χlf, χARM/χlf) and density (σ, gm/cc) depicted significant higher order temporal variation. The χlf varies between 13 and 309 x 10-8m3/kg and is independent of density variation. The χARM, B(0)CR and S-Ratios indicate majority of SD-PSD ferrimagnets with episodes of MD ferrimagnetic concentration and few hard coercivity components. The giant plagioclase lath bearing (GPB) horizons show highest variability of ferrimagnetic concentration marked by anomalous peaks. Overall the variability of rock magnetic parameters independent of lava flow units suggest that the changeover in magnetic mineral concentration, composition and domain size occur at major episodes in magma composition (e.g., primary source, crustal contamination and fractional crystallization). The studied parameters are therefore examined to mark intervals of (i) magma compositional changes, (ii) zones of oxidative conditions and (iii) rapid/slow cooling intervals demanding detailed petrologic studies. We identified one I order trend, four II order cycles and eight III order cycles for the purpose of correlation. Notable peak in χlf at 650–700m, the changeover in rock magnetic parameters at ∼930 m and ∼280 m can facilitate marker intervals while several higher order variations can be adopted for high resolution correlation to other boreholes in the region. The complex variation in rock magnetic parameters independent of flow units reflect temporal magnitudes of compositional variability, cooling and emplacement history that needs detailed petro-mineralogical attempts; and the present data is useful for high order inter-core correlations under the deep drilling program. © 2017, Geological Society of India. 2017 English 00167622 10.1007/s12594-017-0789-2 Journal of the Geological Society of India 90 Geological Society of India 769-775 Department of Geology, Savitribai Phule Pune University, Pune, 411 007, India; CSIR-National Geophysical Research Institute, Hyderabad, 500 007, India 6 basalt; borehole; Deccan Traps; deep drilling; magnetic mineral; mineralogy, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85039442337&doi=10.1007%2fs12594-017-0789-2&partnerID=40&md5=5f014cee521a64c21aa9fe2725fa51c5 cited By 7 S.J. Sangode M. Venkateshwarulu R. Mahajan V. Randive article Mishra2017788 A 1251 m thick succession of Deccan lava flows has been recovered by scientific drilling in the Koyna region, western part of the Deccan Volcanic Province (DVP). Forty-six lava flows, starting with the first flow overlying the granitic basement in the region, have been identified through mesoscopic studies of cores obtained from a 1500 m deep borehole KBH7 in Panchgani village of Patan sub-division. Mesoscopic observations supported by petrographic studies bring out the characteristics of the basaltic pile. The salient findings are as follows. The thickness of Deccan trap in the Panchgani area is 1251.20 m, comprising a succession of 40 simple lava flows and 6 compound lava flows. The contact with the underlying granitic basement occurs over a short span of 90 cm. Infra-trappean sediments are absent. Overall, ∼74% of the basaltic pile is constituted of massive basalt and ∼24% vesicular/amygdaloidal basalt. Red bole horizons are observed in 7 flows. Nine giant plagioclase basalt (GPB) flows are identified in the single vertical section. The long basalt core may serve as a model Deccan trap section for correlation with the flows exposed at the surface in the Koyna and surrounding region and support detailed investigations to constrain the duration of Deccan volcanism. © 2017, Geological Society of India. 2017 English 00167622 10.1007/s12594-017-0792-7 Journal of the Geological Society of India 90 Geological Society of India 788-794 Borehole Geophysics Research Laboratory (BGRL), Ministry of Earth Sciences, Karad, 415 114, India; CSIR-National Geophysical Research Institute, Hyderabad, 500 007, India 6 basement rock; Deccan Traps; drilling; flood basalt; lava flow; petrography; plagioclase; volcanism; volcanology, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85039461106&doi=10.1007%2fs12594-017-0792-7&partnerID=40&md5=791eabdb679ec115ca55804c00882fed cited By 16 S. Mishra S. Misra D. Vyas D. Nikalje A. Warhade S. Roy article Gupta2017151 Koyna, located in the Deccan Volcanic Province in western India, is the most significant site of reservoir triggered seismicity (RTS) globally. The largest RTS event of M 6.3 occurred here on December 10,1967. RTS at Koyna has continued. This includes 22 M> 5.0 and thousands of smaller events over the past 50 years. The annual loading and unloading cycles of the Koyna Reservoir and the nearby Warna Reservoir influence RTS. Koyna provides an excellent natural laboratory to comprehend the mechanism of RTS because earthquakes here occur in a small area, mostly at depths of 2-7 km, which are accessible for monitoring. A deep borehole laboratory is therefore planned to study earthquakes in the near-field to understand their genesis, especially in an RTS environment. Initially, several geophysical investigations were carried out to characterize the seismic zone, including 5000 line kilometres of airborne gravity gradiometry and magnetic surveys, high-quality magnetotelluric data from 100 stations, airborne LiDAR surveys over 1064 km2, drilling of 8 boreholes of approximately 1500 m depth and geophysical logging. To improve the earthquake locations a unique network of borehole seismometers was installed in six of these boreholes. These results, along with a pilot borehole drilling plan, are presented here. © 2017 The Author(s). Published by The Geological Society of London. 2017 English 03058719 10.1144/SP445.11 Geological Society Special Publication 445 Geological Society of London 151-188 CSIR, National Geophysical Research Institute, Hyderabad, India; Borehole Geophysical Research Laboratory, Maharashtra, India; National Centre for Earth Science Studies, Thiruvananthapuram, India; Ministry of Earth Sciences, New Delhi, India 1 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85020047252&doi=10.1144%2fSP445.11&partnerID=40&md5=bfc4c5620ac15fa739e613060629d520 cited By 61 H.K. Gupta K. Arora N.P. Rao S. Roy V.M. Tiwari P.K. Patro H.V.S. Satyanarayana D. Shashidhar C.R. Mahato K.N.S.S.S. Srinivas M. Srihari N. Satyavani Y. Srinu D. Gopinadh H. Raza M. Jana V.V. Akkiraju D. Goswami D. Vyas C.P. Dubey D.C.V. Raju U. Borah K. Raju K.C. Reddy N. Babu B.K. Bansal S. Nayak article Tiwari2017795 A high-resolution, optical core scan laboratory has been set up at Borehole Geophysics Research Laboratory (BGRL), Ministry of Earth Sciences (MoES), Karad. The facility provides a DMT® CoreScan3 optical core scanner and digital drill core data management system for core logging and analysis since July 2016. High resolution images are being produced in 360° mode for detailed unwrapped full circumference of drill core or plane mode for top surface image of slabbed drill core. Planar images of fractured cores and cuttings are also obtained. Image resolution ranges from 5 pix/mm (∼16 megapixel equivalent) to 40 pix/mm (∼1024 megapixel equivalent) for mapping of ultra high resolution data. The scanned core images are combined to create a digital core library. The facility helps in core sample analysis, structural analysis, textural and grain-size analysis, geotechnical studies, and integration with geophysical log data. © 2017, Geological Society of India. 2017 English 00167622 10.1007/s12594-017-0793-6 Journal of the Geological Society of India 90 Geological Society of India 795-797 Borehole Geophysics Research Laboratory (BGRL), Ministry of Earth Sciences, Karad, 415 114, India 6 core logging; data management; digital image; grain size; image resolution; mapping; pixel; texture, India; Karad; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85039444255&doi=10.1007%2fs12594-017-0793-6&partnerID=40&md5=dca72002e46ee13ac5a1bdf1a8b1dd8f cited By 3 S. Tiwari S. Mishra G. Srihariprasad D. Vyas A. Warhade D. Nikalje V. Bartakke B. Mahesh P. Tembhurnikar S. Roy article Misra2017776 The Koyna region, located in the Deccan Flood Basalt Province of western peninsular India has been experiencing reservoir triggered seismicity since the impoundment of the Shivajisagar water reservoir in 1962. Scientific drilling carried out to 1522 m depth in the vicinity of the seismogenic zone exposed the granitic basement that lay below the Deccan Traps and provided a unique opportunity to study the rock types, petrological characteristics and microstructures. Cores obtained from drilling at four sites considered to be representative of the Koyna region, were studied. The boreholes include KBH-1 (Rasati) in the northern part, KBH-5 (Phansavle) in the western part, KBH-6 (Ukhalu) and KBH-7 (Panchgani) in the eastern part of the region. Each borehole penetrates the entire pile of Deccan basalt and pass through a few hundred metres of the granitic basement. The salient results are as follows: (i) The basement granitoids are dominantly composed of granite-gneiss, granite and migmatitic gneiss, typical of cratonic gneiss exposed in peninsular India. (ii) Petrology and microstructure study confirm the occurrence of strained quartz and unstrained plagioclase feldspars in the basement granitoids. (iii) Localized fault zones within the basement section, with prominent evidences of fault breccia, fault gouge, slicken lines with slickensides and pseudotachylite veins are observed in the individual boreholes. (iv) Anastomosing fracture network within these fault zones are good pathways for water channelization, which is supported by the higher abundances of ferruginous and siliceous secondary precipitations following the fractures. © 2017, Geological Society of India. 2017 English 00167622 10.1007/s12594-017-0790-9 Journal of the Geological Society of India 90 Geological Society of India 776-782 Borehole Geophysics Research Laboratory (BGRL), Ministry of Earth Sciences, Karad, 415114, India; CSIR-National Geophysical Research Institute, Hyderabad, 500007, India 6 basalt; basement rock; Deccan Traps; drilling; gneiss; granite; microstructure; petrology; seismic zone, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-85039452603&doi=10.1007%2fs12594-017-0790-9&partnerID=40&md5=c6c5d1ed23696d33e7ec55fedd369314 cited By 22 S. Misra V. Bartakke G. Athavale V.V. Akkiraju D. Goswami S. Roy article Gupta2017641 2017 English 00167622 10.1007/s12594-017-0770-0 Journal of the Geological Society of India 90 Geological Society of India 641-644 CSIR- National Geophysical Research Institute, Hyderabad, 500 007, India 6 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85039438089&doi=10.1007%2fs12594-017-0770-0&partnerID=40&md5=5fc2e73fd628b651bf2e305e32d8e551 cited By 6 H.K. Gupta article Shashidhar2016661 The Koyna region located near the west coast of India has been continuously having artificial water-reservoir-triggered earthquakes since the impoundment of Koyna Dam in 1962. To improve the accuracy of locations of these triggered earthquakes, a unique network of eight borehole seismometers surrounding the seismicity was designed. Five of these have been installed at depths varying from 1134 to 1522 m, well below the Deccan basalt cover. As it is difficult to install the borehole seismometers with desired orientation of the horizontal components, amplitudes of P waves were used to decipher the true orientations after installation. Analysis of data for the period March-June 2015 demonstrated that there is a remarkable increase in the number of earthquakes located with the help of borehole seismometers. Using the existing network of 21 broadband surface seismometers, 184 earthquakes of ML ≥ 0:5 were located; however, with the borehole seismometers, the number of the located events increased to 888 such events. The data also indicate an increase in seismic activity corresponding to the period of increase in the rate of emptying of the Koyna and Warna reservoirs. 2016 English 08950695 10.1785/0220150210 Seismological Research Letters 87 Seismological Society of America 661-667 Seismology Division, Council of Scientific and Industrial Research-National Geophysical Research Institute (CSIR-NGRI), Cyber Building Uppal Road, Hyderabad, Telangana, 500007, India 3 Geophysics; Reservoirs (water); Seismic waves; Seismographs; Seismology, Analysis of data; Artificial water; P waves; Seismic activity; Seismic networks; Triggered Earthquakes; West coast, Earthquakes, borehole geophysics; earthquake mechanism; P-wave; reservoir impoundment; reservoir-induced seismicity; seismicity; seismograph; trigger mechanism, India; Koyna Dam; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-84975873869&doi=10.1785%2f0220150210&partnerID=40&md5=492e398f1c94370ff669e5094d165bd9 cited By 20 D. Shashidhar H.V.S. Satyanarayana C.R. Mahato K. Mallika N.P. Rao H.K. Gupta article Gupta20151511 Artificial water reservoir-triggered earthquakes have continued at Koyna in the Deccan Traps province, India, since the impoundment of the Shivaji Sagar reservoir in 1962. Existing models, to comprehend the genesis of triggered earthquakes, suffer from lack of observations in the near field. To investigate further, scientific deep drilling and setting up a fault zone observatory at depth of 5–7 km is planned in the Koyna area. Prior to undertaking deep drilling, an exploratory phase of investigations has been launched to constrain subsurface geology, structure and heat flow regime in the area that provide critical inputs for the design of the deep borehole observatory. Two core boreholes drilled to depths of 1,522 and 1,196 m have penetrated the Deccan Traps and sampled the granitic basement in the region for the first time. Studies on cores provide new and direct information regarding the thickness of the Deccan Traps, the absence of infra-Trappean sediments and the nature of the underlying basement rocks. Temperatures estimated at a depth of 6 km in the area, made on the basis of heat flow and thermal properties data sets, do not exceed 150 °C. Low-elevation airborne gravity gradient and magnetic data sets covering 5,012 line km, together with high-quality magnetotelluric data at 100 stations, provide both regional information about the thickness of the Deccan Traps and the occurrence of localized density heterogeneities and anomalous conductive zones in the vicinity of the hypocentral zone. Acquisition of airborne LiDAR data to obtain a high-resolution topographic model of the region has been completed over an area of 1,064 km2 centred on the Koyna seismic zone. Seismometers have been deployed in the granitic basement inside two boreholes and are planned in another set of six boreholes to obtain accurate hypocentral locations and constrain the disposition of fault zones. © 2014, Springer-Verlag Berlin Heidelberg. 2015 English 14373254 10.1007/s00531-014-1128-0 International Journal of Earth Sciences 104 Springer Verlag 1511-1522 National Disaster Management Authority, New Delhi, India; CSIR-National Geophysical Research Institute, Hyderabad, India; Ministry of Earth Sciences, New Delhi, India 6 borehole; deep drilling; earthquake; earthquake hypocenter; fault zone; heat flow; lidar; reservoir; seismic zone; seismicity; trigger mechanism, Deccan; India; Koyna; Maharashtra, Calluna vulgaris https://www.scopus.com/inward/record.uri?eid=2-s2.0-84940961358&doi=10.1007%2fs00531-014-1128-0&partnerID=40&md5=dcc1ce1290012760f6d9cec1270f0616 cited By 69 H. Gupta N. Purnachandra Rao S. Roy K. Arora V.M. Tiwari P.K. Patro H.V.S. Satyanarayana D. Shashidhar K. Mallika V.V. Akkiraju D. Goswami D. Vyas G. Ravi K.N.S.S.S. Srinivas M. Srihari S. Mishra C.P. Dubey D.C.V. Raju U. Borah K. Chinna Reddy N. Babu S. Rohilla U. Dhar M. Sen Y.J. Bhaskar Rao B.K. Bansal S. Nayak article Pearson201413 We are currently developing a proposal for a new International Continental Scientific Drilling Program (ICDP) project to recover a stratigraphic and paleoclimatic record from the full succession of Eocene hemipelagic sediments that are now exposed on land in southern Tanzania. Funding for a workshop was provided by ICDP, and the project was advertised in the normal way. A group of about 30 delegates assembled in Dar-es-Salaam for 3 intensive days of discussion, project development, and proposal writing. The event was hosted by the Tanzania Petroleum Development Corporation (TPDC) and was attended by several geologists, geochemists, geophysicists, and micropaleontologists from TPDC and the University of Dar-es-Salaam. International delegates were from Canada, Germany, India, Ireland, Italy, the Netherlands, United Kingdom, and United States (and we also have project partners from Australia, Belgium, and Sweden who were not able to attend). Some of the scientists are veterans of previous scientific drilling in the area, but over half are new on the scene, mostly having been attracted by Tanzania's reputation for world-class paleoclimate archives. Here we outline the broad aims of the proposed drilling and give a flavor of the discussions and the way our proposal developed during the workshop. A video of the workshop with an introduction to the scientific goals and interviews of many of the participants is available at http://vimeo.com/107911777. 2014 English 18168957 10.5194/sd-18-13-2014 Scientific Drilling 18 Copernicus GmbH 13-17 School of Earth and Ocean Sciences, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom; Tanzania Petroleum Development Corporation, Lumumba Street, Dar-es-Salaam, Tanzania Drilling; Energy resources, Continental scientific drillings; Hemipelagic sediments; Paleoclimatic record; Petroleum development; Project development; Scientific drilling; Southern Tanzania; Tropical climates, Stratigraphy https://www.scopus.com/inward/record.uri?eid=2-s2.0-84926312146&doi=10.5194%2fsd-18-13-2014&partnerID=40&md5=51db75ba69a25852351377560e03bb39 cited By 0 P.N. Pearson W. Hudson article Gupta20145 We report here the salient features of the recently concluded International Continental Scientific Drilling Program (ICDP) workshop in Koyna, India. This workshop was a sequel to the earlier held ICDP workshop in Hyderabad and Koyna in 2011. A total of 49 experts (37 from India and 12 from 8 other countries) spent 3 days reviewing the work carried out during the last 3 years based on the recommendations of the 2011 workshop and suggesting the future course of action, including detailed planning for a full deep drilling proposal in Koyna, India. It was unanimously concluded that Koyna is one of the best sites anywhere in the world to investigate genesis of triggered earthquakes from near-field observations. A broad framework of the activities for the next phase leading to deep drilling has been worked out. 2014 English 18168957 10.5194/sd-18-5-2014 Scientific Drilling 18 Copernicus GmbH 5-9 National Disaster Management Authority, New Delhi, India; Ministry of Earth Sciences (MoES), Prithvi Bhavan, Lodi Road, New Delhi, 110003, India; Earthquake Science Center, U.S. Geological Survey, Menlo Park, CA, United States; CSIR-National Geophysical Research Institute, Hyderabad, 500007, India; National Center for Antarctic and Ocean Research, MoES, Goa, 403804, India Drilling; Energy resources, Continental scientific drillings; Course of action; Deep drilling; Detailed planning; Near fields; Salient features; Scientific deep-drilling; Triggered Earthquakes, Earthquakes https://www.scopus.com/inward/record.uri?eid=2-s2.0-84926341111&doi=10.5194%2fsd-18-5-2014&partnerID=40&md5=71c8b811e10d55f0cf059c4e861c61cc cited By 9 H. Gupta S. Nayak Y.J.B. Rao S. Rajan B.K. Bansal N. Purnachandra Rao S. Roy K. Arora R. Mohan V.M. Tiwari H.V.S. Satyanarayana P.K. Patro D. Shashidhar K. Mallika article Roy2013 2013 Feb 01 0974-6889 10.1007/s12594-013-0034-6 Journal of the Geological Society of India 81 289-290 2 https://doi.org/10.1007/s12594-013-0034-6 Sukanta Roy N. P. Rao Vyasulu V. Akkiraju Deepjyoti Goswami Mrinal Sen B. K. Bansal Shailesh Nayak article Yadav2013965 New empirical relations are derived for source parameters of the Koyna-Warna reservoir-triggered seismic zone in Western India using spectral analysis of 38 local earthquakes in the magnitude range ML 3.5-5.2. The data come from a seismic network operated by the CSIR-National Geophysical Research Institute, India, during March 2005 to April 2012 in this region. The source parameters viz. seismic moment, source radius, corner frequency and stress drop for the various events lie in the range of 1013-1016 Nm, 0.1-0.4 km, 2.9-9.4 Hz and 3-26 MPa, respectively. Linear relationships are obtained among the seismic moment (M0), local magnitude (ML), moment magnitude (Mw), corner frequency (fc) and stress drop (Δσ). The stress drops in the Koyna-Warna region are found to increase with magnitude as well as focal depths of earthquakes. Interestingly, accurate depths derived from moment tensor inversion of earthquake waveforms show a strong correlation with the stress drops, seemingly characteristic of the Koyna-Warna region. © 2013 Springer Science+Business Media Dordrecht. 2013 English 0921030X 10.1007/s11069-013-0745-4 Natural Hazards 69 Kluwer Academic Publishers 965-979 CSIR-National Geophysical Research Institute, Hyderabad, India; National Disaster Management Authority, New Delhi, India 1 earthquake event; earthquake magnitude; earthquake trigger; focal mechanism; reservoir-induced seismicity; seismic moment; seismic zone; source parameters; spectral analysis; stress analysis; waveform analysis, India https://www.scopus.com/inward/record.uri?eid=2-s2.0-84884908631&doi=10.1007%2fs11069-013-0745-4&partnerID=40&md5=dca0b4830100b3daeb3309139da37a13 cited By 13 A. Yadav D. Shashidhar K. Mallika N.P. Rao S. Rohilla H.V.S. Satyanarayana D. Srinagesh H. Gupta article Mallika2013189 It is generally found that the b values associated with reservoir-triggered seismicity (RTS) are higher than the regional b values in the frequency magnitude relation of earthquakes. In the present study, temporal and spatial variation of b value is investigated using a catalog of 3,000 earthquakes from August 2005 through December 2010 for the Koyna-Warna region in Western India, which is a classical site of RTS globally. It is an isolated (30 × 20 km2) zone of seismicity where earthquakes of up to M ~5 are found to occur during phases of loading and unloading of the Koyna and Warna reservoirs situated 25 km apart. For the Warna region, it is found that low b values of 0. 6-0. 9 are associated with earthquakes of M ~4 during the loading phase. The percentage correlation of the occurrence of an M ≥ 4 earthquake with a low b value outside the 1σ or 2σ level is as high as 78 %. A drastic drop in the b value of about 50 % being reported for an RTS site may be an important precursory parameter for short-term earthquake forecast in the future. © 2012 Springer Science+Business Media B.V. 2013 English 13834649 10.1007/s10950-012-9318-3 Journal of Seismology 17 Kluwer Academic Publishers 189-195 National Geophysical Research Institute (CSIR-NGRI), Uppal Road, Hyderabad, India 1 earthquake event; earthquake magnitude; earthquake precursor; earthquake prediction; earthquake trigger; loading; reservoir-induced seismicity; seismic isolation; temporal variation; unloading, India; Koyna; Maharashtra; Warna https://www.scopus.com/inward/record.uri?eid=2-s2.0-84871079528&doi=10.1007%2fs10950-012-9318-3&partnerID=40&md5=d27664a84120253a7d6463cc8698fc95 cited By 21 K. Mallika H. Gupta D. Shashidhar N.P. Rao A. Yadav S. Rohilla H.V.S. Satyanarayana D. Srinagesh article Shashidhar20131345 The 14 April 2012 earthquake of Mw 4.8 is the best monitored event in the Koyna region, a globally significant site of reservoir triggered seismicity in western India. Hence, investigation of this event assumes great importance, also considering its epicentral location close to that of the 1967 Koyna earthquake of M 6.3, the world's largest reservoir triggered earthquake. Inversion of P-wave amplitude data along with the first motion polarities at 30 digital seismic stations provides a well-constrained strike-slip type focal mechanism solution, similar to that of the 1967 earthquake. The mechanism is further confirmed by moment tensor inversion of 3-component waveform data recorded at the three nearest broadband stations. The depth distribution of the aftershocks clearly delineates a NNE-SSW trending fault plane dipping about 78° to the WNW and coinciding with the trend of the Donachiwada fault, as well as the left-lateral fault plane of the focal mechanism solution obtained. The precise location, focal mechanism and the seismicity distribution from our dense network indicate that the activity in the Koyna region is mainly controlled by the NNE-SSW trending Donachiwada (D) fault zone rather than the Koyna River Fault Zone (KRFZ) on the west as suggested previously. © 2013 Springer Science+Business Media Dordrecht. 2013 English 13834649 10.1007/s10950-013-9396-x Journal of Seismology 17 1345-1353 National Geophysical Research Institute (CSIR-NGRI), Uppal Road, Hyderabad, 500007, India; National Disaster Management Authority (NDMA), New Delhi, 110029, India 4 active fault; aftershock; earthquake event; fault zone; focal mechanism; moment tensor; reservoir-induced seismicity; seismotectonics, India; Koyna; Maharashtra; Warna https://www.scopus.com/inward/record.uri?eid=2-s2.0-84885035914&doi=10.1007%2fs10950-013-9396-x&partnerID=40&md5=76610c4f195e6874e8139b377b542fd5 cited By 18 D. Shashidhar N.P. Rao D. Srinagesh H. Gupta H.V.S. Satyanarayana G. Suresh A. Satish article Gupta201153 2011 English 18168957 10.2204/iodp.sd.12.07.2011 Scientific Drilling 53-54 National Geophysical Research Institute (CSIR-NGRI), Uppal Road, Hyderabad, 500 007, India; Ministry of Earth Sciences (MoES), C.G.O. Complex, Lodhi Road, New Delhi 110 003, India 12 https://www.scopus.com/inward/record.uri?eid=2-s2.0-83455263847&doi=10.2204%2fiodp.sd.12.07.2011&partnerID=40&md5=0e33bc4ef29c208a01c0b418f1abcb4b cited By 22 H. Gupta S. Nayak article 2011 Journal of Geological Society of India 77 488-490 https://indianjournalofcapitalmarkets.com/index.php/jgsi/article/view/58204/45478 H. Gupta S. Nayak Y.J. Bhaskar Rao R.K. Chadha B.K. Bansal D. Srinagesh N. Purnachandra Rao S. Roy article Gupta20115 Earthquake activity is monitored in real time at the Koyna reservoir in western India, beginning from August 2005 and successful short term forecasts have been made of M ∼ 4 earthquakes. The basis of these forecasts is the observation of nucleation that precedes such earthquakes. Here we report that a total of 29 earthquakes in the magnitude range of 3.5 to 5.1 occurred in the region during the period of August 2005 through May 2010. These earthquakes could broadly be put in three zones. Zone-A has been most active accounting for 18 earthquakes, while 5 earthquakes in Zone-B and 6 in Zone-C have occurred. Earthquakes in Zone-A are preceded by well defined nucleation, while it is not the case with zones B and C. This indicates the complexity of the earthquakes processes and the fact that even in a small seismically active area of only 20 km × 30 km earthquake forecast is difficult. © 2011 Geological Society of India. 2011 English 00167622 10.1007/s12594-011-0001-z Journal of the Geological Society of India 77 5-11 National Geophysical Research Institute (CSIR), Uppal Road, Hyderabad 500 007, India 1 earthquake magnitude; earthquake prediction; nucleation; observational method; seismic zone, India; Koyna; Maharashtra https://www.scopus.com/inward/record.uri?eid=2-s2.0-79952608176&doi=10.1007%2fs12594-011-0001-z&partnerID=40&md5=9f8c97e25c3c441f9486e6e8d16caf3d cited By 21 H. Gupta D. Shashidhar K. Mallika N.P. Rao D. Srinagesh H.V.S. Satyanarayana S. Saha R.T.B. Naik