泌阳凹陷核桃园组烃源岩有机地化特征及热演化成熟史  

Organic geochemical characteristics and thermal evolution maturity history modeling of source rocks in Eocene Hetaoyuan Formation of Biyang Sag,Nanxiang Basin

作　　者：董田[1] 何生[1] 林社卿[2] 

机构地区：[1]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 [2]中国石化河南油田分公司勘探开发研究院,河南南阳473132

出　　处：《石油实验地质》2013年第2期187-194,共8页Petroleum Geology & Experiment

基　　金：国家自然科学基金项目(41072093);中国石化河南油田分公司科研项目(P07057-2)资助

摘　　要：南襄盆地泌阳凹陷有效烃源岩层系主要发育在始新统核三下、上段咸水湖或盐湖相沉积时期,岩性主要为深灰、褐灰、灰色泥岩、钙质泥岩和白云质泥岩。核三下段和上段泥岩平均有机碳含量分别为1.60%和2.23%;核三下段干酪根类型主要为Ⅱ型,其次为Ⅲ型;上段主要为Ⅱ1型,其次为Ⅰ型和Ⅲ型,反映沉积环境的生标化合物以低Pr/Ph比值和高伽马蜡烷含量为特征;泥岩有机质成熟度Ro值介于0.5%～1.4%,主要处在生油阶段,现今门限深度约为1 820 m。在凹陷南部陡坡带和深洼区,核三下段底部最早在37 Ma达到生烃门限,对应的深度约为2 500 m,温度约为100℃;上段顶部最早在23 Ma达到生烃门限,对应的深度约为1 950m,温度约为90℃。核二段泥岩有机碳平均含量为1.85%,有机质类型以Ⅰ型和Ⅱ型为主,主体未进入成熟门限。Abstract： In the Biyang Sag of the Nanxiang Basin, effective hydrocarbon source rock system mainly develops in the lagoon or salt lake facies strata in the lower and upper parts of the 3rd member of the Hetaoyuan Formation. The source rocks include dark gray, brown gray, gray mudstones, calcareous mudstones and dolomitic mudstones. The average organic carbon contents of the lower and the upper parts of the 3rd member of the Hetaoyuan Formation are 1.60% and 2.23%, respectively. Kerogens of the lower part of the 3rd member of the Hetaoyuan Formation are mainly of type Ⅱ, and part of them are of type m. In the upper part of the 3rd member of the Hetaoyuan Forma- tion, kerogens are mainly of type Ⅱ1 , and part of them are of types Ⅰ and Ⅲ. Pr/Ph ratio which illustrates deposi- tional environment is low and gammacerane content is high. Organic matter maturity values （Ro） range from O. 5% to 1.4%, indicating for oil generation stage with current threshold depth of approximately 1 820 m. In the southern steep slope and deep depression, source rocks at the bottom of the 3rd member of the Hetaoyuan Forma- tion enter the threshold for hydrocarbon generation at 37 Ma, and the corresponding depth and temperature are 2 500 m and 100 ℃. At the top of the upper part, the threshold for hydrocarbon generation is at 23 Ma, and the corresponding depth and temperature are 1 950 m and 90 ℃. The average organic carbon content of the 2nd member of the Hetaoyuan Formation is 1.85%. Organic matter types are mainly Ⅰand Ⅱ , having not entered the mature threshold.

关 键 词：有机地化特征 热演化史模拟 烃源岩 核三段 泌阳凹陷 南襄盆地 

分 类 号：TE122.113[石油与天然气工程—油气勘探]