Hydrocarbon Generation And Expulsion History Of Organic Matter-Rich Shale In The Northeastern And Southeastern Chongqing

The Lower Cambrian in the South is an important area for shale gas exploration.The research in this paper focuses on the Lower Cambrian in the northeastern YunnanSoutheastern Yunnan region,including the three sets of organic-rich shale including the Lujiaping Formation,the Shuijing Formation and the Niutitang Formation.The paper analyzes the sedimentary-burial history of the source rock strata to determine the relationship between burial history,tectonic evolution history,thermal evolution history and hydrocarbon generation and expulsion history to analyze the hydrocarbon generation efficiency and history.Then,based on the analysis of the organic matter abundance and type of each source rock,combined with its burial history and thermal history data,the basin simulation software is used to simulate the thermal maturation history of the source rock and the history of hydrocarbon generation and discharge.To classify the hydrocarbon generation and expulsion period of source rocks.By studying the burial history,thermal evolution history and hydrocarbon generation and hydrocarbon history of the three organic-rich source rocks,the thermal evolution of the source rocks is mainly from the Cambrian-Silu,the Permian-Triassic.The influence of the Jurassic-Cretaceous.During the entire geological history,three major hydrocarbon generation and hydrocarbon generation occurred.Corresponding to the middle and late Caledonian,Indosinian and Yanshanian periods.The source rock of the Shuijing Formation reached 0.55% in the Middle Ordovician Ro,entered the oil-generating threshold,and reached the peak of oil production at 0.7% of the Late Ordovician Ro.It reached 1.30% in the Early Permian,and began to get angry and late.The Permian Ro reached 2.0%,and the source rock was in the stage of over-mature thermal evolution.During the Middle and Late Permian period to the early Jurassic,during this period,it was a major stage of anger.The source rocks of the Shuijing Formation began to expel hydrocarbons in the Early Silurian and quickly reached the peak of hydrocarbon expulsion.The early Ordovician Ro of the Lujiaping Formation source rock reached 0.55% and entered the oil generation threshold.The Lujiaping Formation shale reached 1.30% in the Middle Silurian and Late Devonian Ro,respectively,and began to be angry,reaching 2.0% in the Late Carboniferous and Middle Permian,respectively,and the source rock was in the mature stage.The Lujiaping Formation entered the hydrocarbon generation threshold in the Late Cambrian,began to produce large amounts of hydrocarbons and quickly reached the peak of hydrocarbon generation.At the end of the Early Silurian period,the sedimentary discontinuities began to enter the mature stage,and the large-scale hydrocarbon generation occurred during the Middle Permian.The end of the process.The Lower Cambrian Niutitang Formation reached 0.55% in the middle and late Cambrian Ro,entered the oil-producing threshold,reached 0.7% in the Middle Ordovician Ro,entered the peak of oil production,and the shale of the Niutitang Formation was in the middle two The world and the late Devonian Ro reached 1.30% and began to get angry.They all reached 2.0% in the Late Permian,and the source rocks began to enter the stage of mature thermal evolution.In the middle and late Cambrian,the Niutitang group entered the hydrocarbon generation threshold in turn.