Sedimentary Characteristics and Their Controlling Factors of Lower Cretaceous Fan Deltas in Saidong Sub-Sag of Saihantala Sag, Erlian Basin, Northeastern China

Fan deltas of the Lower Cretaceous area in Saihantala sag, Erlian Basin have been identified as major petroleum exploration opportunities. The sedimentary evolution is, however, still debatable, which hinders insights into its controlling factors. This research employed new core observations, thin section and grain size analyses 28 wells Saidong sub-sag, together with numerous borehole seismic data points, to explore lithofacies types, subfacies, microfacies characteristics, thus leading a further investigation facies sag findings showed there are 3 categories, 12 sub-categories, 20 fine types sub-sag. Additionally, various sand-conglomerate were characterized by lower composition texture maturity. With dentate-shaped, box-bell-shaped, other morphological well-logging responses, fan mostly developed A’ershan Formation Tengge’er Formation, could be subdivided three subfacies eight microfacies. Given features characteristics each microfacies, it can determined that main stages occurred formations from Tengge’er: water transgression, oscillation, regression. Moreover, delta deposits regulated primarily semi-arid hygrothermal paleoclimate paleotectonic