Abstract:

The upper member of Eh₃ in Biyang fault-depression includes 3 terrigenous sequences with the span ages of 1.08 Ma,1.40 Ma and 1.02 Ma respectively.A depositional system of fluvial fanfan delta-lacustrine facies was developed in ShuangheZhao'ao region of the depression.The 3 terrigenous sequences consist of 13 parasequence sets,more than 50 recognizable parasequences and 10 microfacies.The accommodation change curves of the terrigenous sequences were obtained by using Fischer diagram.The accommodation variation process and the terrigenous sequence response characters of the uper member of Eh₃ in ShuongheZhao'ao area during deposition were simulated by the application of quantitative sequence stratigraphic simulation system.The results indicate that the terrigenous sequences of the study area formed under the condition of high and uniform velocity of material source supply,and that S4 sequence of TST should be taken as important target for hydrocarbon exploration.

Key words: Fischer diagram, terrigenous sequence, processresponse, simulation, Biyang fault-depression