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百色盆地是一个典型的第三纪走滑拉分盆地,印度板块与欧亚板块碰撞造山造成右江断裂带先左行(距今20~50 Ma)后右行(距今20 Ma以来)是盆地形成较确定的构造背景。盆地分田东、头塘和莲塘3个坳陷,那笔和那葛2个隆起。坳陷形成于NW向左行左阶排列断列的重叠、错列处,而隆起形成于NW向左行右阶排裂断裂的重叠、错列处。其构造演化分为六吜—洞均前拉盆期、那读—建都岭拉分期和建都岭末—第四系后拉分期3个主要构造阶段,每个阶段具有明显不同的特征。通过盆地有机质镜质体反射率、磷灰石裂变径迹和流体包裹体综合研究表明,百色盆地的热演化程度总体较低。仅那读组生油岩达到低熟,极少数为成熟,其它生油岩层未成熟。盆地热演化总的规律是:从距今大约55 Ma开始,古地温随着坳陷沉降和沉积而逐步增加,并于距今大约 25~35 Ma达到最大值。然后随着地壳缓慢抬升,地层温度逐渐变冷。热演化程度低是控制百色盆地油气远景较差的主要原因。
The Baise basin is a typical Tertiary strike-slip subbasin. The collision of the Indian plate with the Eurasian plate caused the left bank of the Youjiang fault zone (20-50 Ma) and the right bank (since 20 Ma) Basin to form a more definite tectonic setting. The basin sub-Tin East, Tau Tong and Liantang 3 depression, that pen and that Ge 2 uplift. The depression is formed at the overlapped and misplaced areas left-aligned to the left of the NW and formed at the overlapped and misplaced areas of the right-order rupture faults at NW to the left. The tectonic evolution is divided into three major structural stages: Liuqian-Cave Precambrian stage, that of the Read-Devdulala stage and the end of the Jiandulingling-Quaternary stage, with distinct features in each stage. Through the study of vitrinite reflectance, apatite fission track and fluid inclusions in the basin, a comprehensive study shows that the thermal evolution of the basin is generally low. Only that group of raw oil rocks reach low-maturity, very few mature, other oil-bearing rock formations immature. The general law of thermal evolution in the basin is that from about 55 Ma, the paleo-geothermal temperature gradually increases with the deposition and deposition of the depression and reaches its maximum at about 25-35 Ma. Then as the crust rises slowly, the temperature of the formation becomes cooler. The low degree of thermal evolution is the main reason for controlling the poor oil and gas prospects in the Bose basin.