Sub-layer Correlation And Sedimentary Microfacies Of The Lower Part Of Yabus Fm. In Palogue Oilfield Of SuDan

Palogue oilfield, located in the north of Mulet Basin in SuDan, is an area where a lot of discoveries of oil and gas have been made by CNODC in recent years. But the focus of the Yabus oil layer of Palogue Area is not understood . Using the theory and technology of high-resolution sequence stratigraphy, the paper carries out the division of high-resolution sequence stratigraphy of the lower part of Yabus Fm. in Palogue area. Based on these researches, sub-layer correlation and sedimentary microfacies of braided- river are studied. Doing all these is in order to provide a geological basis for further exploration and reservoir development. The braided-river model of the Yabus Fm. are established.Through core observation, analyzing well log stacking patterns change, identifying the base-level cycles, four short-term base-level cycles in the 5th order sequence are divided in the lower part of Yabus Fm.. Moreover, as short-term base-level cycle a unit, high-resolution sequence stratigraphy framework is constructed and characters of sequences are analyzed in the sequence framework. Under the control of high-resolution sequence stratigraphic framework, fine sub-layer correlation is studied, and 9 genetic stratigraphic sub-layers are divided in Yabus oil layer by phase sequence and facies association recognized,relation of braided channel, determing the reservoir fluid consistency.Braided river sedimentary type are identified by the research of core, electrofacies . Braid river sedimentary facies classify as braided channel,bar, overflow, flood plain.Formation sedimentary characteristics was changing to meandering river from bottom to top.Through the sand rate statistics and preparation of sedimentary microfacies distribution maps, the sedimentary microfacies distribution in each sub-layer of Yabus Substratum.The braided river mode of Yabus Substratum are established.The research is are providing accurate geological model for fluid flow unit and distribution of interbeds. All of the findings provide a scientific basis for depth exploration and fine development in palogue oil field of Sudan.