With the increasing need for exploration and development, lithologic reservoir has become an important domain for oil and gas exploration in southwestern Qaidam Basin. However, due to multiphase tectonic overprinting activities, the distribution of lithologic reservoir in southwestern Qaidam Basin is indistinct and the next exploration area is indefinite. Through this study, seismic activity is found to be very intensive in southwestern basin due to the influence of basin edge and northwestern second order fault. Seismites related to earthquake are found in deep and shallow beds. Lots of deformation structures are found, such as small step faults, liquid sandstone dikes, vibrating liquid curling structures, sand volcanos, flame structures, pseudoconcretions, seismite sand pillows, seismite sand ball structures, pinch and swell structures, etc. Some rock types are also observed, such as folding seismites, cracked seismites, autoclastic breccias, intraclastic subbreccias. In fact, these smites can greatly increase the permeability of reservoir, which provides a new perspective for oil and gas exploration and development. More importantly, the paleoearthquake is a significant event that triggers seismites, initiates a landslide at the delta front easily, and creates some sediment phenomenon, such as slump fans and turbidities. This kind of reservoir will become a new growth point of reserves. With this thought, by seismic pre-stack multi-attribute prediction and advanced pre-stack AVO inversion prediction, slip blocks are found on Yuedong ramp region in southwestern Qaidam Basin and deposition model is built correspondingly. This might be a breakthrough of previous exploration ideas of \"search for oil around sags\" in this area. It is clearly put forward that paleosag is still an important exploration domain for lithologic reservoirs.