Lithofacies-Logging Phase Characteristics And Genesis Analysis Of Carbonate Conglomerate Facies Of Shahejie Formation In Shulu Sag

It is challenging to make significant exploration progress since the Shahejie Formation conglomerates in the Shulu Sag of the Jizhong Depression are poorly defined and the superposition mode is unknown.Based on the stratigraphic and sedimentary phase delineation of the Shahejie Formation,combined with macroscopic(geophysical)and microscopic(core)characteristics,we conducted research on the petrographic and logging phases and genesis of carbonate conglomerates in this thesis.We have constructed logging identification templates for different conglomerate phases to predict the conglomerate spreading,and primarily obtained the following results:It is challenging to make significant exploration progress since the Shahejie Formation conglomerates in the Shulu Sag of the Jizhong Depression are poorly defined and the superposition mode is unknown.Based on the stratigraphic and sedimentary phase delineation of the Shahejie Formation,combined with macroscopic(geophysical)and microscopic(core)characteristics,we conducted research on the petrographic and logging phases and genesis of carbonate conglomerates in this thesis.We have constructed logging identification templates for different conglomerate phases to predict the conglomerate spreading,and primarily obtained the following results:There are 8 tertiary sequences and 16 system domains in Shahejie component.There are four types of sedimentary facies,namely near-shore subfacies,fan delta,braided river delta and lake,which are refined into 10 types of sedimentary subfacies and 15 types of sedimentary microfacies.Based on the characteristics of rock structure,the conglomerate is divided into granular supported conglomerate and basic-supported conglomerate.With the restrictions of grinding circularity and sorting,it can be divided into seven lithofacies.Among them,the support type can effectively reflect the properties of transport fluid,the basic-supported supports reflect the fluid properties of gravity flow,and the grain supports reflect the fluid properties of high flow traction flow.The logging identification results of typical wells show that the complex base supporting conglomerate is most developed in the steep slope zone,and the gentle slope zone is mainly located at the bottom of the sequence.Grain supported conglomerate mainly developed in gentle slope zone,steep slope zone mainly developed in the top of sequence.Combined with seismic attribute constraint,the distribution of conglomerate in four tectonic evolution stages is determined.It is believed that tectonic activity is the main controlling factor of the distribution characteristics of conglomerate body,and provenance,climate and sedimentary environment all have certain constraints on the distribution of conglomerate body.