Sedimentary characteristics of alluvial fan in the Lower Karamay Formation in Yizhong Area of Karamay Oilfield

By the observation and description of the core wells in Yizhong Area of Karamay Oilfield,the sedimentary microfacies were researched form the aspects of outcrop and core data,log data,logging,construction.Based on sedimentary characteristics and phase sign,single-well phase analysis and multi-wells comparison were made to determine the top-down evolution process through the alluvial fan to River to Delta.According to the evolution law of sedimentary facies,the depositional mode of this area was established based on the combination of macro geological background and micro sedimentary characteristics.