Total Electron Content and Anomalous Appearance of GPS Satellites as Pointers to Epicentre Identification of Major Japan Earthquake of 2011

摘要

The paper presents an analysis of variations in Total Electron Content (TEC) observed through Global Positioning System (GPS) at Guwahati (26?10'N, 91?45'E), in relation to the Japan Earthquakes (EQs) of March 9 and 11, 2011. For this purpose, the azimuthal positions and trajectories of abnormally increased number of satellites at the epicentre location appearing into the Field Of View (FOV) of GPS antenna at Guwahati and consequent pseudo enhancement in TEC are taken as inputs. The paper discusses how the analysis results could provide warning alarms of two earthquakes possibly one on March 8 or 9 and the other on March 11 or 12, 2011 with epicenter positions around 135?E to 145?E and 35?N to 40?N, that coincides with location of Japan Earthquakes. A projected forecast on EQ magnitude of M > 8.5 is also made. The explanations to the observed modifications in TEC features and abnormal increase in number of satellites are purported to be the result of coupling between lithosphere and troposphere forced in by pre-earthquake processes that had spread the zone of activities to as far as Guwahati.