The state of stress in the aftershock area of the March 11, 2011 Tohoku earthquake

3rd National scientific conference with foreign participants "Geodynamical Processes and Natural Hazards"

生态环境科学

Rebetsky, Yu L^1 ; Yu Polets, A.^2

Laboratory of Tectonophysics, Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences, Bolshaya Gruzinskaya Street, 10-1, Moscow

123242, Russia^1

Laboratory of Seismology, Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of Sciences, Nauki Street, 1-B, Yuzhno-Sakhalinsk

693022, Russia^2

关键词: 2011 tohoku earthquakes;    Continental slope;    Discontinuous displacement;    Earthquake focal mechanisms;    Mega earthquakes;    Seismic focal zone;    Stress inversion;    Tohoku earthquakes;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/324/1/012005/pdf
DOI  :  10.1088/1755-1315/324/1/012005

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

This paper presents the results of the stress inversion in the Earth's crust in the Japanese seismic focal zone after the Tohoku earthquake of March 11, 2011. The stress tensor parameters are determined using the method of cataclastic analysis (MCA) of discontinuous displacements. The reconstruction of the stress state is based on earthquake focal mechanism data for magnitude range (Mw) 3.0-6.0. The calculations are performed at six depths. The 2011 Tohoku earthquake brought significant stress changes in the upper layers of the lithosphere of the continental slope (0-30 km). These changes have led to the emerging of extensive areas of horizontal extension here. The areas with changed geodynamic regime were not reduced over the past few years. The magnitude 9.0 Tohoku earthquake was a catastrophic mega earthquake and in this case the presence of an anomalous state of stress may take a long time.