Quantitative Study on Activity Intensity of the Growth Faults and its Hydrocarbon Accumulation Significations in Muglad

Growth faults widely developed during the main three rifting phases from Early Cretaceous to Tertiary in Muglad basin. The quantitative analysis of fault activity in different rifting phase is meaningful to understand the hydrocarbon distribution rules. Ancient fault sliding distance can be used as the quantitative study of growth faults, which can reflect fault activity intensity in different rifting phase directly for rifting basin. The calculation method by seismic data is effective and realizable. The relationship curve of fault ancient fault sliding rate and length and sliding distance distribution are used to study the fault development model and characteristics. The key growth faults and the related oil discovery are analyzed. For the study area in Muglad basin, the linking location during growth fault development corresponds to the paleohigh in early rifting phases, which is the favorable zone of hydrocarbon accumulation. The fault activity in Late Cretaceous is the key factor of hydrocarbon accumulation, when source rock mainly matured and entered into oil-generating peak. The fault activity in Early Cretaceous controlled the quality of source rock. The palaeo oil reservoir can be destroyed and readjusted by the faults activity in Tertiary and new oil reservoir would form in the shallow formation.