The Study on Identification Method of oil Bearing Property in Oil-water Transition Zone of X Development Zone

Abstract The Oilfield where the development zone is located has a unified oil-water contact. The oil-water transition zone in LSX Oilfield is about 24m thick, and the oil layer thickness is about 10m/5m. The OOIP are about 250 million tons. At the early stage of development, about the upper 1/3 section of transition zone was perforated, and the rest lower 2/3 section was not perforated due to high water content, which has become one of the replacement potential in the oilfield. In order to effectively develop this potential, it is necessary to establish the identification standard of oil bearing in the transition zone and explain the oil content at different depths in order to accurately tap the potential of transition zone. Based on the core well data, oil test data, liquid production profile data, closed core well and well logging data, the identification method of oil bearing in the transition zone is determined. The oil content interpretation standard in SPG oil layer is established by using the parameters of mobile water saturation and bound water saturation, and the longitudinal and plane distribution characteristics of oil-prone or water-prone layers in O/W transition zone are implemented. The transition zone was divided into four levels. They are oil-prone, water-prone, oil-bearing, and aquifers respectively, which provide geological basis for exploring the potential of transition zone in different water cut stages in future.