The researchers studied the sedimentary microfacies of the Chang 6 oil-bearing member in the Zhangcha area of the Ordos Basin. They analyzed well logging data from over 140 wells and various laboratory analyses to identify different types of sedimentary microfacies. The main microfacies found were underwater distributary channels, mouth bars, and distributary bays, with the underwater distributary channels being the main location for oil and gas enrichment. The researchers concluded that understanding the distribution of sand bodies in these microfacies can help guide future exploration and development efforts in the area.