NISCAIR Online Periodicals Repository

Research Journals >
Indian Journal of Radio & Space Physics (IJRSP) >
IJRSP Vol.41 [2012] >
IJRSP Vol.41(5) [October 2012] >

Title: A search for precursors of earthquakes from multi-station ULF observations and TEC measurements in India
Authors: Chauhan, Vishal
Singh, O P
Pandey, Uma
Singh, Birbal
Arrora, B R
Rawat, Gautam
Pathan, B M
Sinha, A K
Sharma, A K
Patil, A V
Keywords: Earthquake
ULF anomalies
Total electron content (TEC)
Ionospheric precursors
Issue Date: Oct-2012
Publisher: NISCAIR-CSIR, India
PACS No.: 91.30.pd; 94.20.dv; 94.20.Vv
Abstract: Ground based observations have been carried out for ultra low frequency (ULF) precursors of earthquakes at four different stations in India, namely Agra (geographic lat 27°N, long 78°E), Guttu (lat 31.53°N, long 78.75°E), Shillong (lat 25.92°N, long 91.88°E) and Kolhapur (lat 16.40°N, long 74.15°E) using identical 3-component search coil magnetometers (f = 0.01-30 Hz) obtained from Lviv Centre of Space Research, Ukraine. An offline analysis of the combined data has been carried out in relation to a major earthquake of magnitude M=7.9 occurred in the neighbouring country China (lat 31°N, long 103.32°E, depth=19 km) under the National Program of Earthquakes Precursors (NPEP) launched in India since May 2009. The results of the analysis show occurrence of amplitude anomalies as precursors whose amplitudes decrease with distance. The precursor periods range between 2 and 5 days and are large for the stations nearer to epicenter. A graphical determination of location of the epicenter has been found to be satisfactory with errors within 20.5%. Further, the total electron content (TEC) data obtained from a dual frequency GPS receiver at Agra station and global ionospheric maps (GIMs) of TEC corresponding to the Wenchuan earthquake have also been analysed. The GIM TEC data have been analysed for five different locations which lie between Agra and the epicenter of the earthquake. The anomalies in TEC data are investigated by using quartile based statistical process. It has been found that GPS and GIM TEC data show anomalous depletions of 02 - 13 days before and anomalous enhancements of 03 - 10 days prior to the occurrence of earthquake.
Page(s): 543-556
CC License:  CC Attribution-Noncommercial-No Derivative Works 2.5 India
ISSN: 0975-105X (Online); 0367-8393 (Print)
Source:IJRSP Vol.41(5) [October 2012]

Files in This Item:

File Description SizeFormat
IJRSP 41(5) 543-556.pdf967.41 kBAdobe PDFView/Open
 Current Page Visits: 152 
Recommend this item


Online Submission of Articles |  NISCAIR Website |  National Knowledge Resources Consortium |  Contact us |  Feedback

Disclaimer: NISCAIR assumes no responsibility for the statements and opinions advanced by contributors. The editorial staff in its work of examining papers received for publication is helped, in an honorary capacity, by many distinguished engineers and scientists.

CC License Except where otherwise noted, the Articles on this site are licensed under Creative Commons License: CC Attribution-Noncommercial-No Derivative Works 2.5 India

Copyright © 2015 The Council of Scientific and Industrial Research, New Delhi. All rights reserved.

Powered by DSpace Copyright © 2002-2007 MIT and Hewlett-Packard | Compliant to OAI-PMH V 2.0

Home Page Total Visits: 170571 since 01-Sep-2015  Last updated on 30-Jun-2016Webmaster: