High-frequency sequence stratigraphic division and correlation for the WZ11-4N Oil Field in the Weixinan depression by using the Milankovitch theory

The strata in the 1st member of the Liushagang Formation are explored with the aid of the Milankovitch theory for the selected wells of the WZ11-4N Oil Field in the Weixinan depression. The spectral analysis of the natural gamma-ray spectral logs shows that the strata in the 1st member strata of the Liushagang Formation are dominantly controlled by the 401 ka, 125 ka and 95 ka eccentricity cycles. The high-resolution astronomical timescale is based on the major Milankovitch curves for the 1st member of the Liushagang Formation. The 125 ka eccentricity curves are used as the referenced curves for the 6th-order sequence stratigraphic division and conduct the high-resolution cyclic stratigraphic division and correlation, and finally the division and correlation of the sedimentary facies within the high-resolution stratigraphic framework in the 1st member of the Liushagang Formation.