4. FORECASTING EARTHQUAKES USING GPS MONITORING NETWORK
Monitoring and forecasting earthquakes via GPS mainly reflected in the following aspects:
1) Firstly, the opposite movement among plates was researched using GPS monitoring network. With several
decades of efforts, both the value and direction of relative movement had been measured, and the results were
coincident with the results inferred by geological method, to confirm the plate movement. For example, in
China in the early 1990s, "modern crustal movement and Geodynamics Research" planning topics were
implemented, laid the 22 non-retesting of GPS stations throughout the country. 22 nonscheduled measure GPS
stations were established. After re-testing seven edge, the result indicated that the main energy of striking the
movement of Chinese land plate was derived from the Indian plate pushing the Eurasia in northern direction,
with pushing volume to 3.4 × 10 -8 / A. At the same time, a series of north-south rhombus blocks between
southwestern region of Jinsha River and the North-South Red River fault zone did have a very significant
sliding in the south and a little west, where southward slide was 1.8 cm /a, and westward slide was about 1.0 cm
/a. The establishment and improvement of GPS monitoring network would no doubt provide new knowledge
and understanding for the plate structure and division. GPS research on non-rigid internal characteristics of
plates and plate boundaries types were under way, and they would provide new evidence for monitoring and
forecasting earthquakes.
2) Secondly, Using GPS monitoring network, tectonic activity area in particular the crustal deformation
cumulative in earthquakes, volcanic activity areas was monitored. According to location and the structural
characteristics of Southern California, in the region scientists processed a large number of works to monitor
crustal deformation, and made a lot of important reference value in forecasting earthquakes; in the Soviet
Union, the use of geodetic monitoring accumulation of elastic deformation and vertical stem fault laid GPS
stations was stressed to detect bending characteristics of the rock displacement; in Japan's earthquake prediction
program, crustal deformation observation was a very important project, and a variety of means was participated
in geodesy. But in recent years GPS had been used to do this work, crustal deformation information was also
acquired in earthquake preparation process; using GPS monitoring data in western Yunnan, our country
monitored the apparent activities in the Jianchuan - Lijiang fault and the Red River fault zone. According to
active faults and deformation of the inversion, in the 1993 a magnitude of 6.8~7.0 earthquake was forecasted to
happen in the fault zone, but in 1996 in Lijiang, a magnitude of 7.0 earthquake occurred. The distance between
the practical epicenter and the forecast epicenter was only 30 km, and the validity of GPS was confirmed.
3) Thirdly, Using GPS had characteristics of real-time and continuity, the position displacement curve in
earthquake monitoring process, with seismic released energy data, and the study of crustal stress provided
monitoring and forecasting for aftershocks.
4. FORECASTING EARTHQUAKES USING GPS MONITORING NETWORKMonitoring and forecasting earthquakes via GPS mainly reflected in the following aspects:1) Firstly, the opposite movement among plates was researched using GPS monitoring network. With severaldecades of efforts, both the value and direction of relative movement had been measured, and the results werecoincident with the results inferred by geological method, to confirm the plate movement. For example, inChina in the early 1990s, "modern crustal movement and Geodynamics Research" planning topics wereimplemented, laid the 22 non-retesting of GPS stations throughout the country. 22 nonscheduled measure GPSstations were established. After re-testing seven edge, the result indicated that the main energy of striking themovement of Chinese land plate was derived from the Indian plate pushing the Eurasia in northern direction,with pushing volume to 3.4 × 10 -8 / A. At the same time, a series of north-south rhombus blocks betweensouthwestern region of Jinsha River and the North-South Red River fault zone did have a very significantsliding in the south and a little west, where southward slide was 1.8 cm /a, and westward slide was about 1.0 cm/a. The establishment and improvement of GPS monitoring network would no doubt provide new knowledgeand understanding for the plate structure and division. GPS research on non-rigid internal characteristics ofplates and plate boundaries types were under way, and they would provide new evidence for monitoring andforecasting earthquakes.2) Secondly, Using GPS monitoring network, tectonic activity area in particular the crustal deformationcumulative in earthquakes, volcanic activity areas was monitored. According to location and the structuralcharacteristics of Southern California, in the region scientists processed a large number of works to monitorcrustal deformation, and made a lot of important reference value in forecasting earthquakes; in the SovietUnion, the use of geodetic monitoring accumulation of elastic deformation and vertical stem fault laid GPSstations was stressed to detect bending characteristics of the rock displacement; in Japan's earthquake predictionprogram, crustal deformation observation was a very important project, and a variety of means was participatedin geodesy. But in recent years GPS had been used to do this work, crustal deformation information was alsoacquired in earthquake preparation process; using GPS monitoring data in western Yunnan, our countrymonitored the apparent activities in the Jianchuan - Lijiang fault and the Red River fault zone. According toactive faults and deformation of the inversion, in the 1993 a magnitude of 6.8~7.0 earthquake was forecasted tohappen in the fault zone, but in 1996 in Lijiang, a magnitude of 7.0 earthquake occurred. The distance betweenthe practical epicenter and the forecast epicenter was only 30 km, and the validity of GPS was confirmed.3) Thirdly, Using GPS had characteristics of real-time and continuity, the position displacement curve inearthquake monitoring process, with seismic released energy data, and the study of crustal stress providedmonitoring and forecasting for aftershocks.
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