Abstract: In the Tarim River area within the Taklimakan desert, the Tarim Basin, the ideal time for feld seismic survey is the frost period dating from December to next January or February. When the wide azimuth 3D seismic survey was conducted within the Well YML2 South 3D area in 2014, the break-up period during February arrived in advance. The width, boundary and phreatic surface elevation of the Tarim River varied dramatically. During the break-up period, as the climate changed greatly, the Tarim River transgressed and regressed frequently, while breaking-up and freezing usually alternated, leading to the varying coverage and number of shot point and receiver point flooded. As a result, the seismic survey across the Tarim River could not be carried out as it was previously designed. With consideration to the fact that the changing hydrogeologic conditions during the break-up period have adverse impacts on the seismic survey, the operation scheme was updated or adjusted. The high precision remote sensing information technology was applied to trace and understand the variation of hydrogeologic conditions in real-time manner. According to the thought and method of initial dynamic design and rolling optimal design for observation system, the shot points and receiver points in the Tarim River hazard were timely migrated, resumed or increased, and fne seismic operation was organized orderly, in order to ensure the normal parameters during the frost period. The application results show that high-resolution wide azimuth 3D data with high S/N ratio were acquired.

Key words: Tarim River hazard, wide azimuth 3D, seismic survey, break-up period, initial dynamic design, rolling optimal design