苏北盆地盐城凹陷天然气和凝析油的地球化学特征和成因  

THE GEOCHEMICAL CHARACTERISTICS AND ORIGIN OF NATURAL GAS AND CONDENSATES IN YANCHENG SAG, SUBEI BASIN

作　　者：包建平[1] 毛凤鸣[2] 段云鹏 马安来[1] 朱翠山[1] 侯建国[2] 王文军[2] 

机构地区：[1]长江大学地球化学系湖北荆州,434023 [2]中石化江苏油田分公司,江苏扬州225009 [3]昆明高级冶金专科学校,云南昆明650033

出　　处：《天然气地球科学》2004年第2期103-109,共7页Natural Gas Geoscience

摘　　要：根据对盐城凹陷上白垩统泰州组天然气的化学组成和碳同位素组成特征的综合分析和对上白垩统泰州组、下第三系阜二段不同有机质类型烃源岩热模拟气态产物的碳同位素分析结果,认为盐城凹陷泰州组天然气属于干酪根高成熟阶段热裂解成因的干气,气源岩层主要是下伏的上古生界,但部分泰州组烃源岩对产气也可能有贡献;与天然气伴生的凝析油则主要来自于泰州组烃源岩,这与高成熟的干气在上侵过程中对油藏原油的气洗作用有关。Based on the chemical compositions and steady carbon isotope of natural gases from Taizhou formation in Yancheng sag, Subei basin, and combined with the results of carbon isotope of gases from the thermal simulation of K_(2)t and Ef_(2) source rocks with different organic matter types, the natural gases are dry gas derived from thermal cracking of type-Ⅲ kerogen. They are mainly generated from the underlying upper Paleozoic source rocks. The condensates accompanying with dry gases are primarily derived from (K_(2)t) source rocks. The formation of condensates is related to gas washing which results in the fractionation of crude oils in upper oil reservoirs.

关 键 词：天然气 凝析油 碳同位素 气洗作用 成熟度 地球化学特征 

分 类 号：TE122.1[石油与天然气工程—油气勘探]