The relation between plate tectonics and earthquake evolution is analyzed systematically on the basis of 1998-2010 absolute and relative gravity data from the Crustal Movement Observation Network of China. Most earthq...The relation between plate tectonics and earthquake evolution is analyzed systematically on the basis of 1998-2010 absolute and relative gravity data from the Crustal Movement Observation Network of China. Most earthquakes originated in the plate boundary or within the fault zone. Tectonic deformation was most intense and exhibited discontinuity within the tectonically active fault zone because of the differential movement; the stress accumulation produced an abrupt gravity change, which was further enhanced by the earthquake. The gravity data from China's Mainland since 2000 obviously reflected five major earthquakes （Ms 〉 7）, all of which were better reflected than before 2000. Regional gravity anomalies and a gravity gradient change were observed in the area around the epicenter about 2 or 3 years before the earthquake occurred, suggesting that gravity change may be a seismic precursor. Furthermore, in this study, the medium-term predictions of the Ms7.3 Yutian, Ms8.0 Wenchuan, and Ms7.0 Lushan earthquakes are analytically pre- sented and evaluated, especially to estimate location of earthquake.展开更多
The April 20, 2013, Ms7.0 Lushan earthquake was successfully recorded by closely spaced Continuous Global Positioning System （CGPS） stations owned by the Crustal Movement Observation Network of Chi- na （CMONC）. Th...The April 20, 2013, Ms7.0 Lushan earthquake was successfully recorded by closely spaced Continuous Global Positioning System （CGPS） stations owned by the Crustal Movement Observation Network of Chi- na （CMONC）. The 1-Hz GNSS data from eight CGPS stations, which are located between 30 km and 200 km from the hypocenter, were processed within quasi-real-time. The near-field surface deformation indicated the following characteristics ： the near-field movements were limited to several centimeters ; the peak of the deformation wave was significantly larger than the static permanent offset; at the beginning of the event, the north wall of the fault moved to the southeast as the south wall moved to the southwest ; station SCTQ, which was the closest station to the hypocenter at 30 km, had the largest static permanent displacement of 2 cm; the peaks of the deformation waves were 1.5 cm, 5 cm and 3 cm, to the east, the south and vertically upward, respectively ; and the peaks of velocity and acceleration, derived from the deformation, were 3.4 cm/s and 5.3 cm/s^2,respectively.展开更多
基金jointly funded by the Shanxi Science and Technology Plan Projects(2014K13-04)the Special Earthquake Research Project Grant offered by the China Earthquake Administration(201508009)the Crustal Movement Observation Network of China
文摘The relation between plate tectonics and earthquake evolution is analyzed systematically on the basis of 1998-2010 absolute and relative gravity data from the Crustal Movement Observation Network of China. Most earthquakes originated in the plate boundary or within the fault zone. Tectonic deformation was most intense and exhibited discontinuity within the tectonically active fault zone because of the differential movement; the stress accumulation produced an abrupt gravity change, which was further enhanced by the earthquake. The gravity data from China's Mainland since 2000 obviously reflected five major earthquakes （Ms 〉 7）, all of which were better reflected than before 2000. Regional gravity anomalies and a gravity gradient change were observed in the area around the epicenter about 2 or 3 years before the earthquake occurred, suggesting that gravity change may be a seismic precursor. Furthermore, in this study, the medium-term predictions of the Ms7.3 Yutian, Ms8.0 Wenchuan, and Ms7.0 Lushan earthquakes are analytically pre- sented and evaluated, especially to estimate location of earthquake.
基金supported by the National Natural Science Foundation of China(41274027)the Director Foundation of Institute of Seismology, China Earthquake Administration(IS201156063)
文摘The April 20, 2013, Ms7.0 Lushan earthquake was successfully recorded by closely spaced Continuous Global Positioning System （CGPS） stations owned by the Crustal Movement Observation Network of Chi- na （CMONC）. The 1-Hz GNSS data from eight CGPS stations, which are located between 30 km and 200 km from the hypocenter, were processed within quasi-real-time. The near-field surface deformation indicated the following characteristics ： the near-field movements were limited to several centimeters ; the peak of the deformation wave was significantly larger than the static permanent offset; at the beginning of the event, the north wall of the fault moved to the southeast as the south wall moved to the southwest ; station SCTQ, which was the closest station to the hypocenter at 30 km, had the largest static permanent displacement of 2 cm; the peaks of the deformation waves were 1.5 cm, 5 cm and 3 cm, to the east, the south and vertically upward, respectively ; and the peaks of velocity and acceleration, derived from the deformation, were 3.4 cm/s and 5.3 cm/s^2,respectively.
