Cenozoic Basin Development And Evolution In Qingdong Area

Qingdong area is located in the conjunction between Jiyang depression and the Tan-Lu fault zone, which has enrichment conditions for oil and gas in structures, but the evolution and tectonic pattern is not clear at present in Qingdong area, which limited oil and gas exploration and development, so it is important to anlysis the basin develop and evolution in Qingdong area from the basin Geometry and Kinematics.Firstly the geometry of basin were analyzed by using heavier, electric, seismic data in Qingdong area. Qingdong depression and Qingdongdong depression showed a typical half graben basin. there are four groups faults, which are NW, nearly EW, NNE and NE(E) trend since Cenozoic in Qingdong area. Secondly, basin kinematics and basin evolution were analyzed by using the calculation of fault activity, analysis of balanced cross-section, simulation of ANSYS software in the study area. The results show that NW and mostly EW trend faults continue its activities and their maximum activity is in Ek periods, NE, NE(E) trend faults mainly formed in Paleogene and integratedly intense activity in Es4 periods. Qing dong area showed the inheritance of the Early Cretaceous in basin pattern in Ek period. These two depression has not yet separated, which wholely shows a Half graben in basin structure. North West trend basin Pattern is weakened, mainly shows a composite basin pattern in NWW and nearly EW trend. Qingdong and Qingdongdong depression began to sag separated, Only partial still connected in Es4 period. The basin pattern is shows the EW and NE trend in Es3 period. Qingdongdong depression continue to uplift suffered erosion, Qingdong depression, basin pattern mainly shows NE trend in Es2 period. Qingdong depression and Qingdongdong depression showed a raised areas being denuded. Qingnan sag continue to accept deposits, but Deposition range decreas in Es1 to Ed period. Finally, the relationship between the basin evolution in Qingdong area and Tanlu fault were Investigated by comparing the basin structure between Qingdong area and basin around. The results show that the basin structure and evolution of Qingdong depression is similar to Dongying depression, Qingnan depression is in the transition of the two depression. Other wise Qingdongdong depression, Weibei depression and Laizhouwan depression are similar in basin pattern, and Qingdongdong depression is in the transition of the two depression. Tanlu fault should be mainly sinistral strike-slip movement Since the Mesozoic Cretaceous to Paleocene Es4 period. Basin structure initially formed in Qingdong area under its strike-slip, some NW trend associated faults controlling the deposition, Residual strata distribution showed NW, EW trend. Tanlu change ite Sinistral strike-slip to Dextral strike-slip. ME, NNE trends faults appear corresponding in Qingdong depression and Qingdongdong depression. Strata distribution of residues is also from the north west, east to the west, gradually transformed into the north east. basin evolution enter the depression period in Neogene...