The Ziniquanzi Formation in the southern Junggar Basin was studied to understand its sedimentary facies. By comparing outcrop and well logging data, researchers identified different types of sedimentary environments like alluvial fans, braided rivers, deltas, and lakes. They found that the formation can be divided into an upper and lower segment based on mud layers and sedimentary features. The lower segment shows a mix of fan, river, delta, and lake deposits, while the upper segment is dominated by river, delta, and lake sediments.