Sequence Stratigraphy And Sedimentary Facies Of The Guadeloupe Formation In North Perth Basin,Western Australia

The North Perth Basin of Western Australia is located along the coast of southwest Australia.The Permian Guadeloupe system has a long history of oil and gas exploration and excellent oil and gas exploration potential.The exploration status shows that the oil and gas accumulation in this interval is mainly controlled by the distribution of sand bodies,and the distribution of sand bodies in the area is closely related to the type and distribution of sedimentary facies.However,the Guadeloupe system in the study area is characterized by a complex facies,a mixture of terrigenous debris and carbonate rocks,and the study of sedimentary systems in the area is still very weak.In response to this problem,based on the results of previous studies,this paper uses drill well logging data,core data,and rock sheet data to comprehensively apply basic theories and methods of sequence stratigraphy,sedimentary petrology,and sedimentology.The characteristics of the sequence and sedimentary facies of the Guadeloupe in Northern Perth Basin,Western Australia.Based on a detailed understanding of predecessors' research results on the Middle Permian strata in the North Perth Basin,combined with the analysis of seismic profiles,single wells and wells,the various rock types in the Guadeloupe of the North Perth Basin were established.In the contact relationship,it was found that the Wagina sandstone,Dongara sandstone,and Beekeeper formations in the area are not strictly superposed one on top of another,but are different rock types deposited in different phases at the same time;they pass through the Guadeloupe o f the North Perth Basin.The identification of sequence boundaries and the causes of the sequence boundaries were analyzed.The sequence division scheme of Guadeloupe was determined in the North Perth Basin.Three third-order sequences were identified and a three-level sequence was established.Comparing the isochronal stratigraphic framework of the unit;through the study of the sedimentary facies sign of the Guadeloupe in the North Perth Basin and the establishment of a petroelectric model,a study was co nducted on the trend and evolution characteristics of the litho-paleogeographic plane distribution in the study area,pointing out that The sedimentary environment of the Guadeloupe in the Perth Basin has changed from a fan-delta-beach-carbonate lagoon sed imentary system to a braided river-shore-shore-shallow-sea sedimentary system,mainly due to the decline in sea level during the early sedimentation period.Fan delta-shore system area of expanding the role of the latter due to the construction area le ad to strong onshore braided river development,and carbonate rock lagoon has been shrinking.