Segmention growth and linkage of normal fault control the formation of fault-bound traps, in order to investigate implication of fault evolution for formation of fault-bound traps, this paper utilizes the ratio of displacement to overlapping space and displacement gradient to distinguish the stage of fault interaction and insure temporal availability of fault-bound trap. Aiming at fault-bound trap equipped with temporal availability, we use maximum throw subtraction to determine formation time of fault-bound traps, which formed before the oil accumulation period were beneficial for oil accumulation. In this study, Nandagang fault and Koucun fault which located in Qinan slope, Qikou Sag are taken as examples to exert the research of temporal-spatial validity of fault-bound traps. The results show that hydrocarbon distribution was found in fault-bound traps which possessed temporal-spatial validity more frequent than which only equipped with temporal validity or spatial validity. Therefore, carrying out temporal-spatial validity assessment for undrilled fault-bound traps could effectively decrease the risk of exploration and development.
Wang Shunyu Sun Xiaojun Wang Haixue Li Jing Jiang Wenya Cao Xiaofeng Bi Chenyang Chong Jian. Temporal-spatial validity assessment and formation mechanisms of fault-bound trap: Case from Qinan slope, Qikou Sag[J]. Chinese Journal of Geology, 2020, 55(1): 93-108.