The October 20, 2011 Mw 5.1 Talala earthquake in the stable continental region of India     

B. K. Rastogi  Santosh Kumar  Sandeep K. Aggrawal  Kapil Mohan  Nagabhushan Rao  N. Purnachandra Rao  Girish Ch. Kothyari 《Natural Hazards》2013,65(2):1197-1216

The Talala (Sasangir) area in the Saurashtra region of Gujarat, western India, is experiencing tremors since 2001. The swarm type of earthquake activity in 2001, 2004, and every year from 2007 onward has occurred after the monsoon and lasted 2?C3?months each time. In 2007 some 200 shocks (largest M_w 5.0) and in 2011 about 400 shocks down to M1 are well recorded with 1?C2?km location error. The focal depths are about 2?C10?km and shocks are accompanied by blast-like subterranean sounds. The epicenter (21.09?N 70.45E, focal depth: 5?km from location program, 3?km from MTS) of the October 20, 2011 mainshock occurred about 12-km WNW of Talala town or 8-km SSW of the 2007?M _w 5.0 earthquake epicenter. The epicentral trends deciphered from local earthquake data indicate two ENE trends (Narmada trend) for about 50?km length and a conjugate 15-km-long NNW trend (Aravali trend). The focal mechanisms by moment-tensor analysis of full wave forms of two 2007 events of M_w 4.8 and 5.0 and the 2011 event of M_w 5.1 indicate rupture along either of the two trends. The ENE trends follow a gravity low between the gravity highs of Girnar mounts. Seismic reflections also indicate a fault in the area named Girnar Fault. Most of Saurashtra region including the Talala area is covered by Deccan Trap Basalt forming plateaus and conical ridges. There is no major fault within Saurashtra Peninsula though it is believed to have major faults along the boundaries that are non-seismic. The intensity of the October 20, 2011 Talala earthquake is estimated to be 6.5 in MM scale while isoseismals of 6, 5, and 4 and felt distance give M_w 5.1 based on Johnston??s 1994 empirical regressions. The source parameters of the 2011 Talala earthquake are estimated using data from 14 broadband seismograph stations. Estimated seismic moment, moment magnitude, stress drop, corner frequency, and source radius are found to be 10^16.6 N-m, 5.1, 1.6?MPa, 1.3?Hz, and 2,300?m, respectively. The b and p values are obtained to be low, being 0.67 and 0.71, respectively. PGA of 35?cm/sec² is noted and the decay rate of acceleration has been estimated from strong motion data recorded at 5 stations with epicentral distances ranging from 32 to 200?km.  相似文献   

Periodicity analysis of galactic cosmic rays using Fourier,Hilbert, and higher-order spectral methods     

V. Vipindas  Sumesh Gopinath  T. E. Girish 《Astrophysics and Space Science》2016,361(4):135

  相似文献   

Metal enrichment and reionization constraints on early star formation     

J. S. Bagla  Girish Kulkarni  T. Padmanabhan 《Monthly notices of the Royal Astronomical Society》2009,397(2):971-978

  相似文献   

Bio‐hydrogen Production By Enzymic Hydrolysis of Sunflower Oil Sludge          下载免费PDF全文

Punniavan Sakthiselvan  Balakrishnan Naveena  Kannapan Panchamoorthy Gopinath  Nagarajan Partha 《洁净——土壤、空气、水》2015,43(11):1547-1555

  相似文献   

Displacement due to impulsive loadings on the surface of elastic half-space     

Gopinath Sarkar 《Pure and Applied Geophysics》1967,66(1):37-47

Summary The displacement due to vertical impulsive load has been obtained by function theoretic method. Graphs have been drawn for horizontal as well as for vertical displacement. It has been shown thatPekeris's [12]²) method is easier to apply than that ofCagniard [2] for the same purpose.  相似文献   

On uniqueness of dispersion curve of surface love-waves     

Gopinath Sarkar 《Pure and Applied Geophysics》1965,61(1):29-35

Summary Possibility of non-uniqueness of dispersion curve for various distributions of physical properties has been discussed. It has been concluded that number of layers in a model should be moderate in order to give a representative picture.  相似文献   

Identification of groundwater prospective zones using irs-id liss iii and pump test methods   总被引：1，自引：0，他引：1  

Girish Gopinath  P. Seralathan 《Journal of the Indian Society of Remote Sensing》2004,32(4):329-342

The role of hydrogeomorphological units and lineaments in the storage of groundwater from the Muvattupuzha river basin has been investigated using IRS ID LISS III data. Other than the usual water bodies such as river course, reservoirs and ponds, the major hydrogeomorphological units identified in this basin in the descending order of their groundwater potential are: valley fills, moderately dissected plateau, pediments, residual mounts, residual mount complex, linear ridges, residual hills and structural hills. Majority of the lineaments trends in NW-SE and WNW-ESE directions. Even though the eastern part of the basin is characterised by moderate to high lineament density, the above area is found to be poor to moderate groundwater prospect zone because of high gradient and structural hills. The pump test analyses of dug wells from different hydrogeomorphic units also confirm that valley fills are the most promising unit for groundwater prospecting than the rest.  相似文献   

Study on penetration depth and its dependence on frequency,soil moisture,texture and temperature in the context of microwave remote sensing     

K. S. Rao  Girish Chandra  P. V. Narasimha Rao 《Journal of the Indian Society of Remote Sensing》1988,16(2):7-19

A theoretical study has been made to see the influence of microwave frequency, soil moisture, soil texture and soil temperature on penetration depth in the context of microwave remote sensing. The results are presented in the form of figures and also coefficients of least square fitting. The study reveals that there is a definite dependence of penetration depth on the above parameters. The range of penetration depth has been found to be 0 to 10 cms and varies as a function of several parameters. These results are in agreement with experimental observations.  相似文献   

Morpho-hypsometric evolution of the Karuvannur River Basin,a tropical river in central Kerala,southwestern peninsular India     

Arun Bhadran  V. K. Vijesh  Girish Gopinath  Drishya Girishbai  N. P. Jesiya  K. P. Thrivikramji 《Arabian Journal of Geosciences》2018,11(15):430

An integrated morphometric and hypsometric analysis coupled with asymmetric factor used as a proxy for the landscape evolution of the catchment of Karuvannur River. The present study area is a sixth order tropical river in the central Kerala which supplies water and sediments to the Vembanad-Kol Ramsar site. The Karuvannur River Basin (KRB) has been divided into six sub-watersheds (SW). Morphometric parameters (areal, linear, and relief) and hypsometric and asymmetric factors are measured for the delineation of morphotectonic evolution of the area. High values of drainage density, texture, ruggedness number, and hypsometric integral with relatively high volume of leftover rocks in the basin in SW-II and SW-III compared to the entire basin of KRB imply that these two sub-watersheds have been influenced by the tectonic activities. Further, detailed asymmetric data indicated that these two watersheds are tilted in opposite direction. It may be the result of reactivation of Precambrian fault/lineament in recent past. This has been supported by recent tremors and neotectonic studies in Kerala. Moreover, detailed field evidence along with google imagery revealed that the entire basin is a part of regional anticline associated with PCSZ. Geomorphic response to disturbance will produce a sensible, recognizable response; it can be well studied in rivers through detailed study of their sensitivity or behavioral changes. Rivers have an enormous capacity to absorb perturbation and these types of studies are essential for identifying/measuring tectonic activities, sediment diffusion, surface runoff in a drainage basin, and as an important tool for target oriented micro watershed management.  相似文献   

An exploratory study on occurrence and impact of climate change on agriculture in Tamil Nadu,India     

Varadan  R. Jayakumara  Kumar  Pramod  Jha  Girish Kumar  Pal  Suresh  Singh  Rashmi 《Theoretical and Applied Climatology》2017,127(3-4):993-1010

This study has been undertaken to examine the occurrence of climate change in Tamil Nadu, the southernmost state of India and its impact on rainfall pattern which is a primary constraint for agricultural production. Among the five sample stations examined across the state, the minimum temperature has increased significantly in Coimbatore while the same has decreased significantly in Vellore whereas both minimum and maximum temperatures have increased significantly in Madurai since 1969 with climate change occurring between late 1980s and early 1990s. As a result, the south-west monsoon has been disturbed with August rainfall increasing with more dispersion while September rainfall decreasing with less dispersion. Thus, September, the peak rainfall month of south-west monsoon before climate change, has become the monsoon receding month after climate change. Though there has been no change in the trend of the north-east monsoon, the quantity of October and November rainfall has considerably increased with increased dispersion after climate change. On the whole, south-west monsoon has decreased with decreased dispersion while north-east monsoon has increased with increased dispersion. Consequently, the season window for south-west monsoon crops has shortened while the north-east monsoon crops are left to fend against flood risk during their initial stages. Further, the incoherence in warming, climate change and rainfall impact seen across the state necessitates devising different indigenous and institutional adaptation strategies for different regions to overcome the adverse impacts of climate change on agriculture.

  相似文献