Physical Modeling Of Complex Structures In The Lower Yangtze Region

The geological tectonic evolution of the Jurong area experienced early nappe compression and late extension,strong tectonic alteration,complex the fracture and fold,and large dip angle(up to 60 degrees above),causing the recording complex wave field.changing seismic wave propagation path,and affect the next stratum reflection information received.Therefore,it is very necessary to combine the propagation theory of seismic wave in complex media with seismic physical model to meet the requirements of the stage deep fine looking for exploration.Based on geological structure setting of the Jurong region and exploration experience of other blocks in lower Yangtze area,3-D seismic physical modeling of this region was studied here supported from CNPC Key Laboratory of geophysical prospecting,China University of Petroleum(Beijing).Meanwhile we used finite difference method to get data and analyze,process data from numerical modeling and 2-D,3-D seismic physical simulation.Our results show that post-stack migration section exists ambiguous breakpoints,blurry imaging and dislocated diffracted wave under the geological structure of many thrust faults.Moreover,deep imaging effect is not ideal in the shallow fracture zone.kirchhoff pre-stack time migration method for complex structure imaging effect is ideal,especially processing method and processing parameters for the special terrain and the complex geological conditions more rationality by comparing different migration method.