Abstract: The northwestern Tarim Basin is characterized by intense tectonic activity and complex hydrocarbon accumulation conditions, which inhibit a systematic understanding of hydrocarbon distribution patterns in the region. Focusing on the A’Nan, Keping and Wushi blocks, this study analyzes the hydrocarbon accumulation conditions of each block based on the development characteristics of source rocks in northwestern Tarim Basin and the results of oil-source and gas-source correlations. Hydrocarbon accumulation models are established for the respective blocks, and three favorable areas for oil and gas exploration are identified. The results indicate that the source rocks in the southern part of northwestern Tarim exhibit significant lateral variation. The hydrocarbon in the A’nan block mainly sourced from the Lower Cambrian Yuertusi and Xiaoerbulake formations, while in the Keping block primarily originated from the Lower Cambrian Yuertusi formation, both exhibiting near-source charging. In contrast, the hydrocarbon in the northern Wushi block are mainly sourced from the Triassic Huangshanjie Formation and Jurassic Qiakemake Formation source rocks in the eastern Baicheng sag, indicating far-source charging. In terms of hydrocarbon accumulation models, the A’nan block is characterized by “dual-source hydrocarbon supply, fault-controlled migration, and lower-generation but upper-reservoir accumulation”, whereas the Keping block primarily features “near-source hydrocarbon supply, lateral migration, and structure-unconformity composite transport system”. The Wushi block, on the other hand, exhibits a hydrocarbon accumulation model characterized by “far-source hydrocarbon supply, fault-unconformity composite transport system, and accumulation in lower buried-hill traps and upper fault-related traps”. Based on these findings, three favorable areas for oil and gas exploration are identified, i.e., the eastern A’nan block, the western Keping block, and the southeastern Wushi block.

Key words: northwestern Tarim Basin, Keping faulted-uplift belt, A’nan block, Keping block, Wushi block, hydrocarbon accumulation model, Cambrian Yuertusi Formation, Cambrian Xiaoerbulake Formation, Triassic Huangshanjie Formation, Jurassic Qiakemake Formation, Tarim Basin

摘要： 塔里木盆地西北缘（塔西北）地区构造活动强烈，油气成藏条件复杂，制约了该地区油气分布规律的系统认识。聚焦阿南、柯坪和乌什3个区块，基于塔西北地区烃源岩的发育特征，以及油-源、气-源对比结果，分析了不同区块的油气成藏条件，建立了不同区块的油气成藏模式，优选了3个油气勘探有利区。研究结果表明：塔西北地区南部烃源岩的横向变化显著，阿南区块的油气主要来自于下寒武统玉尓吐斯组和肖尔布拉克组烃源岩，柯坪区块的油气主要来自于下寒武统玉尓吐斯组烃源岩，皆表现为近源供烃特征，而北部乌什区块的油气主要源自其东部拜城凹陷的三叠系黄山街组和侏罗系恰克马克组烃源岩，具有远源供烃的特点；成藏模式方面，阿南区块发育“双源供烃、断层输导、下生上储”的油气成藏模式，柯坪区块主要发育“近源供烃、侧向运移、构造-不整合复合输导”的油气成藏模式，而乌什区块则表现为“远源供烃、断层-不整合复合输导、下部潜山和上部断层相关圈闭聚集”的成藏特征。据此优选出阿南区块东部、柯坪区块西部和乌什区块东南部3个油气勘探有利区。

关键词: 塔西北地区, 柯坪断隆带, 阿南区块, 柯坪区块, 乌什区块, 油气成藏模式, 寒武系玉尔吐斯组, 寒武系肖尔布拉克组, 三叠系黄山街组, 侏罗系恰克马克组, 塔里木盆地