Characteristics and effects of the gravity flow channel deposits on the development of the Banqiao Oil Field

The Banqiao Oil Field lies at the pitching end in the northeastern part of the Beidagang buried hill structural zone. The first member of the Shahejie Formation in the oil field is built up of the typical gravity flow channel deposits. The gravity flow channels may be classified, on the basis of core examination and well logs for 400 wells, into five sedimentary microfacies, including main channel, distributary channel, flank channel, overbank and lacustrine mud microfacies. The emphasis of this paper is placed on the distribution of the abovementioned microfacies and their controls on the physical properties of the reservoir sandstones and water drive controls in individual sedimentary microfacies. The potential areas should comprise the main channel, distributary channel and flank channel sandstones, especially the distributary channel sandstones where there occurs prolific residual oil.