塔河油田南部AT1井区中三叠统中油组是最重要的含油气层系，其沉积相类型及其对砂体展布白气储层的控制等地质开发问题倍受重视。文中在地震储层反演、岩心描述和测井分析基础上，结合铸享片、粒度分析等大量测试资料，对该地区中油组沉积相类型及特征进行深入研究的结果表明：塔河油田三叠系AT1井区中油组为湖底扇沉积。该区发育AA、AB型非典型鲍玛序列，并主要发育中扇亚相。该亚相可以识别出辫状水道、水道间漫溢、无水道席状砂等微相，主要储集砂体为中扇辫状水道。该文结合地质背景,探讨了浊积扇的成因机制，并建立了相应的沉积模式。

Middle Triassic Zhongyou Formation in A T1 area of southern Tahe Oilfield is an important oil and gas． beating layer，of which the sedimentary type，sand body distribution，reservoir control and other kinds of geological issues are paid much attention to．Based on seismic inversion，core description and logging analysis，combined with cast thin section and grain size analysis，the sedimentary facies and characteristics are studied．The result shows that Middle Triassic Zhongyou Form ation in AT1 area of Tahe Oilfield belongs to sublacustrine fan deposits，and AA and AB type non—typical Bouma sequence are widely developed．Meanwhile，Zhongyou Formation of AT1 area mainly developed middle fan subfacies，among which braided channel，interchannel overflow，non-channel sand sheet are identified．The main reservoir sand is middle fan—braided channel．Based on the regional geologic setting，the genetic mechanism of turbidite fan is discussed and corresponding sedimentary model is established．