作　　者： ; ; ; ; ; ; ;

机构地区： 中国科学院广州地球化学研究所有机地球化学国家重点实验室

出　　处： 《天然气地球科学》 2007年第3期440-446,共7页

摘　　要： 鄂尔多斯盆地是在单斜构造背景下的稳定台地型盆地，古生代以来一直以整体升降运动为主，在其上古生界已发现榆林气田、乌审旗气田、苏里格气田等，这些气田的烃源岩主要为上古生界煤层，次为暗色泥岩。自三叠纪稳定快速埋藏成熟、早白垩世末受晚期燕山运动影响抬升剥蚀后，盆内古地温明显降低，大部分地区降温幅度太大，生烃基本结束，大部分地区Ro〉1．3％，南部过成熟，向北成熟度逐渐降低。盆内上古生界气源灶有机质丰度高，但（熟化速率）ΔRo≤0．03％／Ma，生气速率主要在（0．2～0．4）×10^8m^3／（km^2·Ma）之间，平均主生气持续时间为104．7Ma，主生气期内的生气量比例为55．9％。 The Ordos basin is located on a stable platform of monoclinal structure, and tectonic movements were mainly elevation and subsidence since the Paleozoic. The Yulin, Wushenqi, Sugeli gas fields are found in the Upper Paleozoic coal measure. The gas resource rock is mainly the Upper Paleozoic coal seams, then dark mudstone. The source rocks were buried and matured quickly since the Triassic, and ceased at the end of the early Cretaceous because of the late Yanshan movement. The Ordos Basin was uplifted and eroded at that time. The Paleotemperature of the resource rocks decreased rapidly, and the amplitude of the temperature falling was so large that the temperature was too low to generate hydrocarbon again. At the end of the early Cretaceous, the vitrinite reflectivity was above 1.3% in the most part of the basin, being overmature in the south and decreased northward. Although the abundance of organic matters is high, but the mature rate of the resource rock is less than 0. 03%/Ma, the gas generation rate is mainly from 0. 2×10^8 m^3/（km^2 · Ma） to 0. 4×10^8 m^3/（km^2· Ma）, the averaged hydrocarbon generation interval is up to 104. 7 Ma, and the percentage of gas generation in the main hydrocarbon generation interval is 55.9 %.

关 键 词： 天然气 气源灶 鄂尔多斯盆地 生烃动力学 上古生界

领　　域： [石油与天然气工程]