1. Key Laboratory of Exploration Technologies for Oil and Gas ��esources��Ministry of Education��Wuhan 430100��China; 2. School of Geoscience��Yangtze University��Wuhan 430100��China; 3. Exploration and Development ��esearch Institute��Huabei Oilfield Company��PetroChina����enqiu��Hebei 062552��China

Based on core observation and description��combined with various marks��such as rock types�� sedimentary structure��fossils and characteristics of logging curve response��the authors analyzed depositional facies and characteristics of Fuyu reservoir (K f ) in Chaochang-Shuangcheng area��eastern Daqing placanticline�� The results show that two types of facies��shallow- water delta and meandering river sedimentary facies are developed in the studied area�� They are further divided into five subphases and eleven microphases�� Types of sand bodies mainly include bed- side beach deposition��delta plain distributary channel sand body��as well as delta front underwater distributary channel sand body�� On this basis��combined with high- resolution sequence stratigraphic division�� Fuyu reservoir can be divided into two long- term cyclic sequences��seven middle- term cyclic sequences�� Sedimen- tary microfacies plane distribution maps are established according to analysis results and the regulations on the plane distribution and vertical evolution are analyzed�� Vertically��changes of depth of water show such procedure: it starts from deep to shallow��and then gradually varies from shallow to deep�� In turning point of MSC4 drop- half cycle to MSC5 rise- half cycle��the depth of water reaches the shallowest value�� ��esults show that the shallow- water delta sedimentary facies are developed in the studied area and types of sand bodies are mainly delta plain�� In this period��river and delta plain are developed in the whole area��channel sand body is in max thickness��and it is the best time for the development of sand body as reservoir��