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We attempted to detect tiny interseismic crustal deformation on the Haiyuan fault using the PS-InSAR method and 17 ENVISAT/ASAR images in descending orbit. The result shows that homogeneity and consistency in space, and stability and linear variance in time characterize deformation rates of PS points in study area. Mean while conspicuous contrast of deformation rates is present on opposite sides of the Haiyuan fault, with a relative motion rate in line of sight about 5mm/a in the central segment. These estimates are in accordance with the results of 2~10mm/yr determined by geological and geodetic methods.

Infrasonic airwaves offer a relatively unfiltered representation of source motions before an earthquake. It necessitates automatic processing of the infrasound as the precursor needs to be sorted before further analysis. An analysis of infrasonic records generated from five seismic case studies is provided in this article. Extracting the physical characters of different signals by signal processing such as Fourier Transform and Wavelets Transform are generally employed to carry out the necessary expansion. In this paper dynamic fuzzy clustering method is developed for classifying the set of multivariate infrasonic time trajectories from the unwanted infrasound sources.

Based on the improved DInSAR technology, this paper obtained the whole coseismic deformation field of Wenchuan Ms8.0 earthquake by 128 frames of Lever1.0 data of ALOS PALSAR. By comparing with the continuous GPS survey results, the precision of coseismic deformation field was estimated as about 9.5cm, better than half-wavelength of L-band. The whole coseismic deformation stripe has a total length of about 300km, which encircles the NE-trend seismic ruptures, and is mostly distributed within 19–100km from the fault rupture. The spatial distribution of coseismic deformation gradually narrows down from southwest to northeast, owing to the fact that the seismic energy gradually decayed along the NE-trend from Yingxiu where the seismic fracture begins to Qingchuan where it ends. There is a weak coherence zone near the seismic rupture relating to strong displacements, such as landslide, mud and rock flow, etc. And this weak coherence zone obviously extends wider in south Beichuan than in north Beichuan, which is corresponding to the fact that two parallel rupture faults exist in south Beichuan while only one exists in north Beichuan. The 471-track deformation is produced mainly by Qingchuan Ms6.4 dextral-strike aftershock and other strong aftershocks, and therefore its deformation field is discontinuous with adjacent tracks. As a whole, northwest plate-Bayankala Block was uplifted, while southeast plate-rigid Sichuan Basin subsided, and both sides of the seismic rupture were uplifted. But there exist one subsided zone 10–30km away from the rupture in the Bayankala Block. Synthetically analysis shows that, under the effect of the huge eastward pushing force from Tibet, the Bayankala Block was resisted by the rigid Sichuan Basin when it thrust along the high-angle seismic rupture, and then its east margin bent to form a subsided zone to absorb and release the strong eastward thrusting force.

Numerical modeling can be used to obtain geophysical information for earthquake mechanism analysis. During the past decade, differential synthetic aperture radar interferometry (D-InSAR) technology has been applied successfully to research co-seismic field and hypocentral mechanism, which could offer more abundant boundary conditions with higher quality as compared with the conventional methodology of geodetic measurement. This paper reports a model of in-depth co-seismic displacement with this approach. On November 14, 2001, a Ms8.1 earthquake, one of the largest events hitting the Chinese mainland over the past 50 odd years, occurred at the Kunlun Mountains in the northern Tibetan plateau, China. In this model, a co-seismic field is established and a series of hypocentral parameters are extracted on the earthquake applying D-InSAR processing with 2Pass+external DEM mode to 20 pair’s ERS-2 SAR data and combined with field geology investigation as well as GPS observations on permanent stations. D-InSAR co-seismic field shows that the Kunlun Mountain Ms8.1 earthquake produced a 430-kilometer-long surface rupture zone, composed by the western section of Taiyang Lake-Kushuihuan with a length of 30km, the eastern section of Bukadaban Peak-Kunlun Mountain Pass with a length of 350km and a 50km long unbroken step area between the above-mentioned two sections. This rupture zone shows such obvious characteristics as distinct segmentation and a left-lateral slip with little reverse component. The maximum co-seismic sinistral horizontal dislocation is 7.38m, of which 4.30m on the south wall and 3.08m on north wall. The maximum vertical dislocation is 4.0m. By means of Poly3D, a geophysical boundary element method (BEM) developed by Stanford University, and based on the boundary conditions of D-InSAR hypocentral parameter, this paper simulates a 3D distribution of the co-seismic deformation and spatial trend of displacement vector over the shock surface area of 80,000 km2 and its underground areas of 20km in depth. The 3D displacement field shows that the maximum strike displacement Ux occurs at 15km below the surface of the Hoh sai Hu lake east-Yuxi peak segment, with a maximum dislocation of 6.424m, the maximum dip displacement Uy is located 10km below the surface of the Yuxi peak-Kunlun Mountain Pass segment, with a maximum dislocation of 2.067m, and the maximum dip displacement Uz is located 10km below the surface of the Yuxi peak-Kunlun Mountain Pass segment with a maximum dislocation of 3.701m. The simulation displacement vectors indicate that bounded by the almost vertical main rupture plane, the south wall thrusts northward with some subsidence, the north wall moves upwards, the south wall moves from west to east while the north wall does from east to west. As the horizontal offset is dominated by left-lateral vertical displacement, the earthquake is classified as a strike-slip dominant type. Thus it is concluded that the Ms8.1 Kunlun earthquake originated from the Kunlun fault with a set of steep dip, left-lateral and strike-slip reverse faults.

In the high resolution images, undamaged buildings take on natural texture features, but to the damaged or extensive damaged buildings, there are always some low grayscale blocks because of their coarsely damaged section. By using such statistical information as the number of holes in every region, or the ratio between the area of the region and the holes', et al., damaged buildings can be separated from undamaged buildings, thus automatic detection of damaged buildings can be reached. Based on these characteristics, in this work, a new method to detect the damage buildings automatically by using region structure and statistic information of the texture is presented. Also, in order to test its validity, 1-meter-resolution iKonos merged image of Bhuj earthquake, India, 2001, and grayscale aerial photos of Tangshan earthquake, China, 1976, are selected as two examples to detect the damaged buildings automatically. Satisfactory results are obtained

The fusion technique of remote sensing image and digital elevation model (DEM) is applied and the 3D image of researched region is made. The landslides are interpreted through the 3D image. The conclusion shows that the proposed method is better than the traditional methods. Landslide is a serious geologic hazard with serious results for the environment and zoology. Remote sensing interpretation is an important means to study the distribution of landslides. The technology of remote sensing three-dimension visualization and image dynamical analysis is synthetically utilizing the remote sensing (RS) and geography information system (GIS) to realize the three-dimension recurring and continuous cartoon of landslides. It provides a advanced method for studying landslides. The critical technology involves in several parts: the data fusion of multi-type RS images, making digital elevation model (DEM), fusion of DEM and image. It will effectively gain the information of landslides of research area through the dynamical analysis technology. We have analyzed some instances with the technology. It shows the three-dimension recurring is an important method for landslide study.

The tectonic evolution of the India-Asia collision provides great insight to the inland deformation of Tibet plateau. There are two radically different interpretations of the development of the Tibet plateau: doubling the crust by the replacement of Tibetan upper mantle by the under thrust Indian continental crust, or by the interior shortening of the Tibet crust by the thrust fault systems in Tibet plateau. Based on the detailed field investigation, the geomorphological markers on the Landsat ETM images at different scales are used to constrain the localization, displacement along the Maergaichaka fault, Tibet, China. By the Chaoyang Lake-Maergaichak Lake, a strike slip system, including a semi-flower structure, which comprises a complex combination of the structural patterns of M-T and M-P was identified. Though there are intensive thrust related structures near the Maergaichak fault, the remote sensing and GPS results indicates that the left-lateral slip of the fault has mainly accommodated the shortening of the India-Eurasian lithospheric plates.