Study Of The Main Engineering Geological Problems Identification Around China-Pakistan Economic Corridor Based On Synthetic Aperture Radar

China-Pakistan Economic Corridor(western structural knots in China’s territory) is mainly along the G314 National Highway. It starts from Kashgar, passing through the Muztagata Mountain and Taxkorgan valley in the Karakoram Mountain zone, and ends in southeastern Pakistan border crossings- Khunjerab. The area is one of the places where glaciers developed and tectonic movements active. The geo-hazards and earthquakes happened frequently, linear-project often being blocked, and people’s lives and property were suffered severe losses. This paper focused on the SAR(synthetic aperture radar) technology application and did the research on the identification of major engineering geological problems. The results are here described:(1) In contrast with the optical remote sensing image, SAR intensity image can penetrate clouds, identifying the geological bodies in the high altitude area with glacier covered, such as glacial tills flow disaster, and be used to set target areas.(2) Based on the permanent-scatter points, we using Small Baseline Subset Interferometric Synthetic Aperture Radar(SBAS-In SAR) technology to identify the engineering geological problems related to the deformation, such as glacier migration, glacial debris flows, landslides creep, wetlands deformation, and determine the deformation scale.(3) The criteria of identification of engineering geological problems: glacier moving monitoring is suggested to use offset_tracking measurement method and abnormal PS points over glacier tongue to judge the motion of upper part of the glacier; the movement of glacial debris flow is mainly according to the accumulation area with high deformation points; creep landslide identification is based on a combination analysis of topography, lithology and PS points reflecting high slope deformation; the moraine distortion is related to the slope and the source of water, thus we can combine the landscape, the "PS points cluster" and the basin scale to analyze the activity; wetland reflected on the SAR intensity image is easy to identify and its deformation is generally shown as positive, negative high value PS points in the line of sight of satellite.(4) The modern glacier movements of the Kongur mountain and the Karakoram Mountain are successfully identified using the Offset_tracking method. Kongur glacier movement rate is greater than the rate of Karakoram Mountain glacier, and the peak deformation rate is 2 times greater than that on the edge of the glacier tongue. Its deformation in winter is large than that in other seasons.(5) The In SAR technology is succeed in the identification of early engineering geological problems research on China-Pakistani economic corridors. The In SAR can efficiently monitor deformation with large scale and continuous spatial distribution, without restriction of natural environment and weather conditions, and can trace back to the historical movement. Therefore, the application of this technology in the initial project planning plays an important demonstration technical support role.