Sedimentary System of Deep Series of Strata in Anpeng Block in Zhaowa Oilfield

Anpeng deep series of strata refer to exploratory targets that are mainly consisted of the lower of H3(the third interval of the Hetaoyuan Formation) with a buried depth over 2800m. The sedimentary mode is fan delta complex near mountains where two subfacies develops, including fan delta front and pre - fan delta. They are subdivided into 6 micro sedimentary facies including near - shore under water distributary channel, far - shore under water distributary channel, rnouth bar, sand sheet, interchannel mud and pre - fan delta mud. Near - shore and far - shore under water distributary channel micro facies are relatively widely distributed in the study area. This set of reservoirs is characterized by compacted and low permeability and the type of sandbody obviously control the physical properties of reservoirs. Reservoirs of medium to far - shore under water distributary channel micro facies have good physical properties, thus are the main oil layers in Anpeng deep series of strata.