摘要
柴达木盆地西部地区第三系为柴达木盆地近年来主要产油区,其中在南翼山地区深浅层均发现含油气层系,单层产量较高。油源对比表明南翼山油田油气来源于小梁山凹陷,近年来,南翼山地区中浅层石油年产量增长较快,已成为新的接替领域。对该区的烃源岩研究表明:小梁山凹陷烃源岩以暗色灰质泥岩、泥灰岩为主,夹少量碳酸盐岩,烃源岩主要分布在下干柴沟组上段(E32)、上干柴沟组(N1)、下油砂山组(N21)、上油砂山组(N22)中,有机碳含量相对较低,但氯仿沥青"A"和总烃含量较高,均在100×10-6以上,最高达到1000×10-6以上,属于好烃源岩;有机质类型主要以Ⅱ型为主,热演化程度从未成熟—成熟阶段均有分布。研究表明,上干柴沟组(N1)、下油砂山组(N21)烃源岩有机质丰度高,生烃潜力大,是该区的主要供油源岩。
The Tertiary System of Western Qaidam Basin has become the major yield area in recent years, where the hydrocarbon-bearing stratigraphy is discovered in the Nanyi Mountain area with the higher production. According to the oil-source correlation, the source derives from the Xiaoliang Mountain Sag in the Nanyi Mountain oilfield. The study on hydrocarbon source rocks indicates that the hydrocarbon source rocks of Xiaoliang Mountain Sag is mainly dark lime mudstone and mud limestone with a little of carbonates; the source rocks are primarily distributed in Lower Ganchiagou Formation (E3^2), Upper Ganchaigou Formation(N1 ), Lower Youshashan Formaiton(N2^1) and Upper Youshashan Formation(N2^2) characterized by low quantity of organic carbon, high quantity of chloroform bitumen A, and total hydrocarbon at the average of 100×10^-6 above (peak value is more than 1 000×10^-6; the organic matter is domiantly type Ⅱ ranging from the immature to mature stages. The hydrocarbon source rocks in Upper Ganchaigou Formation (N1) and Lower Youshashan Formation (N2^1) have high abundance of organic matter and have the great potential to generate hydrocarbons.
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2009年第3期405-410,共6页
Natural Gas Geoscience
基金
国家重点基础研究发展计划("973")项目(编号:2006CB701401
2006CB202305)资助
关键词
柴达木盆地西部
烃源岩
有机质丰度
有机质类型
有机质成熟度
Western Qaidam Basin
Source rock
Organic matter abundance
Organic matter type
Organic matter maturity.