Abstract: This paper studied the well developed fractured structural belt and its developing history, based on the formation of fractured-mudstone oil and gas traps in Qingshankou group in the northern part of Gulong sag. The digenesis history of the mudstone is studied firstly to determine broken condition of mudstone. Laser holographical and speckle interferential tracing technology are used to determine the criticalbroken value of mudstone. Then, Paleo-structure at different geologic ages are used to evaluate the curvature of different structural belt to determine the favorable belt fordeveloping tectonic cracks. Eventually, information on the formation, migration, and accumulation of oil and gas and those on development of structural fissure are integrated to forecast the location of the favourable belt of fractured-shale oil and gas pools.