| Kongnan area is the second oil-rich sag of southern Huanghua Depression, located in Bohai Bay Basin, between Kongdian Salient and Dengmingsi. As demonstrated by many years'petroleum exploration, Kongnan area is abundant of petroleum resources in Ek2 of Kongdian Formation. However, there are some differences in previous researches on deposit sourcees and sedimentary systems.Aimed at the above research meaning and problems, this thesis studying on Ek2 of Kongnan area, analyses its isochronal stratigraphic framework, the types of sedimentary systems and paleo-river systems and basin margin types, then reveals sedimentary systems spatial distributing feature and deposition filling patterns through theories and methods of Sedimentary Geology and Continental sequence stratigraphy. Utilizating the datas of drilling core, well log, seismic and interior testing analysis, based on sedimentary facies indicator analysis, and also according to the characters of rock association, sedimentary structure, section structure and evolutionary series, it identifies 5 types of depositional systems, including braided river delta, meandering river delta, beach bar, tuibidite fan and lake. And the paper establishes typical phase sequences.Utilizating the components of gravel and sandstone, heavy minerals and sandstone bodies dispersion system to analyse paleo-provenances and paleo-river systems, it identifies that there were four provenance areas, Cangxian uplift, Chengning uplift, northern provenance area and southern provenance area. And it developed two types of paleo-river systems, braided river systems and meandering river systems.On basis of the above study, the paper analyses the distributions on space of the sedimentary systems. Controlled by types of basin margin, it summarizes 3 types of sedimentary systems spatial distributing feature, braided river delta - tuibidite fan– lake, meandering river– beach bar– lake, and meandering river– far tuibidite fan– lake.
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