A model of nonuniform fracture system for Langcang-Gengma earthquake sequence and elasto-plastic computation method
Based on the observation data, it is found that the Lancang-Gengma earthquake sequence is resulting from the propagation of a nonuniform fracture system in which the lengths and strikes of fractures are different from each other, the stress field and medium condition around fractures are also heterogeneous. Therefore, a mechanical model simulating suitably the fracture processes of the Lancang-Gengma earthquake sequence is suggested in this paper. The fracture criterions and computation method for elastic fracture and elasto-plastic fracture are studied. The stress intensity factor, strain energy release rate and J-integral are evaluated respectively. The forward and inverse method jointing a variety of observation data to determine the earthquake fracture processes is also developed in this paper.
In the past 19 years,while China's urbanization was fast-developing,a series of problems related to urbanization were there upon production.In this paper,based on spectrum characteristic of knowledge method,the thematic information of three periods of LUCC were extracted from Landsat TM,ETM + and CBERS-2.Combing with the GIS technology,the land-use transfer matrix from 1987 to 2006 were obtained.Besides,the LUCC models were applied to analyze the characteristic of land use change from 1987 to 2006.Based on the land-use change map and land-use transfer matrix,spatial dynamic characteristic and land-use conversion of the study area were analyzed.The research could provide suggestions for land management and making policy for local government.