Sequence division and sedimentary system of Carboniferous in eastern Caohu sag

Based on the principles of T. Cross high resolution sequence stratigraphy, the Carboniferous in the study area is divided into three long- term stratigraphic cycles (corresponding to I - grade sequence), where terrestrial clastic rock sequences are mainly developed, through comprehensive analysis of geologic, drilling, logging and seismic data. Two types of sedimentary system are identified in the study area, including shoreland - fan delta and tidal - lagoon. The component of sedimentary system and the development of source, reservoir and cap rocks in each cycle are analyzed in the framework of sequence stratigraphy. Vertically, the lower LSC2 is relatively favorable reservoir in the study area, while laterally the shoreland -fan delta sandbodies in the vicinity of Caol - Cao6 well-blocks are relatively favorable exploration targets in the study area.