西藏伦坡拉盆地牛堡组一段沉积特征及勘探意义  

Sedimentary Characteristics and Gas-Oil Exploration Significance of the First Member of Niubao Formation in the Lunpola Basin,Tibet

作　　者：刘中戎[1] 曹强[2] 何志勇[1] 

机构地区：[1]中国石化勘探分公司,成都610041 [2]中国地质大学(武汉)构造与油气资源教育部重点实验室,武汉430074

出　　处：《地质科技情报》2017年第6期174-180,共7页Geological Science and Technology Information

基　　金：中国石化勘探分公司"伦坡拉盆地牛堡组沉积储层特征及成藏规律研究"(G0800-14-KK-169);国家自然科学基金项目(40172051)

摘　　要：西藏伦坡拉盆地是经勘探证实的含油气盆地,已提交控制储量721万t,具有一定的勘探潜力。早期油气勘探主要集中在东北部,揭示储层薄、物性差,未取得实质性突破。受低勘探程度制约,牛堡组的已有地质认识存在局限性,尤其是对牛堡组一段在中西部沉积充填模式的认识不够深入。前期认为盆地的断陷期主要发生在牛二段,是盆地烃源岩主发育期。近期研究表明牛堡组一段沉积时期,存在"南主断、西主洼"的盆地格局,西南部为沉积中心,发育较好的烃源岩,打破了早期牛堡组一段为一套红层不发育烃源岩的认识,研究结果对下一步拓宽勘探思路及勘探领域具有重要意义。The Lunpola Basin is an oil and gas-bearing basin confirmed by exploration, with controlled re- serves of 7.21million tones and has a certain exploration potential. Early exploration activities were mainly concentrated in the northeastern part of the basin, the reservoirs revealsed are thin and have poor physical properties. Hence, this kind of discovery can not be taken as a substantial breakthrough. Meanwhile the low exploration degree limits the geological understandings of Niubao Formation, especially for the deposi- tional filling pattern of the first member of Niubao Formation in the central-western part. Previous studies showed that the rifting period of the basin was the depositional period of the second member of Niubao Formation, which should also be the main development stage of source rocks. However, recent studies show that during the depositional period of the first member of Niubao Formation, the basin represented a structural pattern of ＂fault in the south and sag in the west＂. The depocenter is then found to be in the southwestern part, where high-quality source rocks are developed. This understanding is different from previous understanding that the first member of Niubao Formation is a set of red bed and it does not devel- op source rocks. The study results are of great significance to broaden exploration idea and exploration field for the next step.

关 键 词：伦坡拉盆地 烃源岩 牛堡组一段 沉积充填 断陷期 

分 类 号：P588.12[天文地球—岩石学]