In this paper, the plumb line deflection varied with time (PLV) are calculated with the Vening-Meinesz formula for Xiaguan and Beijing point based on the 28 and 39 campaigns of gravimetry at the local gravity networks...In this paper, the plumb line deflection varied with time (PLV) are calculated with the Vening-Meinesz formula for Xiaguan and Beijing point based on the 28 and 39 campaigns of gravimetry at the local gravity networks in the Western Yunnan Earthquake Prediction Experiment Area and the North China, respectively. Based on the results, we conclude that: (1) the maximum of PLV is under 0.1 double prime and amplitudes of interannual variation are under 0.02 double prime . (2) PLV can be determined with the reliability of 0.01 double prime by the modeling based on the precession of repeated gravimetry. This implies that repeated gravimetry could be used to determine the PLV. (3) There exist some common and different characteristics for the different places and different components. It may provide a new approach for the study on the local or global geodynamic by using repeated gravimetry.展开更多
Plumb line variations (PLV) of points at Tangshan and Midu during 1985-1998 are determined by using the 46 batch repeated gravity observations of the Beijing-Tangshan network and 32 batch repeated gravity observations...Plumb line variations (PLV) of points at Tangshan and Midu during 1985-1998 are determined by using the 46 batch repeated gravity observations of the Beijing-Tangshan network and 32 batch repeated gravity observations of the West-Yunan network. As for Tangshan region, relation between underground matter change (UMC) and the PLV on ground are discussed and approach of determining the UMC by a derived regional PLV is found. The UMC before and after earthquake(1995.10.05, Mb 5.0)in Tangshan region, as an example, is studied, giving the location and depth of the mass center of underground disturbing body as well as its mass quantity.展开更多
Plumb line variations(PLV) at Tangshan during the years of 1987―1998 are determined by using the 46 batch repeated gravity observations of the Beijing-Tangshan network.It has been found that PLV at Tangshan are relat...Plumb line variations(PLV) at Tangshan during the years of 1987―1998 are determined by using the 46 batch repeated gravity observations of the Beijing-Tangshan network.It has been found that PLV at Tangshan are related with the 38 earthquakes in this period.It appears that the time of an earthquake around Tangshan is usually quite the same when PLV at Tangshan begins moving in opposite direction.展开更多
基金State Natural Foundation (19373018) and the State Science and Technology Target Project (96-913-04-01-03).
文摘In this paper, the plumb line deflection varied with time (PLV) are calculated with the Vening-Meinesz formula for Xiaguan and Beijing point based on the 28 and 39 campaigns of gravimetry at the local gravity networks in the Western Yunnan Earthquake Prediction Experiment Area and the North China, respectively. Based on the results, we conclude that: (1) the maximum of PLV is under 0.1 double prime and amplitudes of interannual variation are under 0.02 double prime . (2) PLV can be determined with the reliability of 0.01 double prime by the modeling based on the precession of repeated gravimetry. This implies that repeated gravimetry could be used to determine the PLV. (3) There exist some common and different characteristics for the different places and different components. It may provide a new approach for the study on the local or global geodynamic by using repeated gravimetry.
文摘Plumb line variations (PLV) of points at Tangshan and Midu during 1985-1998 are determined by using the 46 batch repeated gravity observations of the Beijing-Tangshan network and 32 batch repeated gravity observations of the West-Yunan network. As for Tangshan region, relation between underground matter change (UMC) and the PLV on ground are discussed and approach of determining the UMC by a derived regional PLV is found. The UMC before and after earthquake(1995.10.05, Mb 5.0)in Tangshan region, as an example, is studied, giving the location and depth of the mass center of underground disturbing body as well as its mass quantity.
基金Supported by the National Natural Science Foundation of China (Grant No.10633030)
文摘Plumb line variations(PLV) at Tangshan during the years of 1987―1998 are determined by using the 46 batch repeated gravity observations of the Beijing-Tangshan network.It has been found that PLV at Tangshan are related with the 38 earthquakes in this period.It appears that the time of an earthquake around Tangshan is usually quite the same when PLV at Tangshan begins moving in opposite direction.
