Sedimentary characteristics and cause of conglomerate in Ying-4 segment of Xushen gas field

This paper discusses conglomerate reservoir of Yingcheng group 4 section , which is one of the main reservoirs in Xingcheng area. Ying 4 section conglomerate reservoir are studied based on subtle core observation, plentiful rock thin-section identification, cast thin-section picture statistic analyses, scanning electron microscope observation and Feature data of conglomerate pore structure by mercury injection method. The collectivity character of conglomerate sediment in Ying 4 section is a very thick celadon massive bedding conglomerate which is grain supported. This paper discusses the macro depositing character of conglomerate of Ying-4 segment. With this foundation, we regard the cause of conglomerate in Ying-4 segment as, transiting to braided river delta, braided-river fan-delta which is shallow and conglomerate, and classify it to three kind of Sedimentary subfacies.