渤海湾盆地临清坳陷东部热演化历史和成烃史  

THERMAL EVOLUTIONAL HISTORY AND HYDROCARBON ACCUMU-LATION IN THE EASTERN LINQING DEPRESSION, BOHAI BAY BASIN

作　　者：吕希学[1] 

机构地区：[1]中国石油化工集团公司胜利油田有限公司勘探处,山东东营257062

出　　处：《地质科学》2006年第4期676-687,共12页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家自然科学基金(批准号:40472066);中国石油化工集团公司"十五"项目(P03007)联合资助。

摘　　要：利用磷灰石裂变径迹和镜质体反射率古温标模拟计算的临清坳陷热演化历史，古地温梯度在总体上是逐渐降低的：孔店组沉积时期为4．2～5．0℃／100m，沙河街组沉积末期地温梯度降低至3．4℃／100m±，但在东营组沉积末期地温梯度有一增高的现象（3．5℃／100m），这可能与东营组沉积末期的抬升剥蚀有关；馆陶组沉积末期降至3．2℃／100m，现今为3．0℃／100m。临清坳陷的现今地温分布和古地温梯度均低于邻区的济阳坳陷、昌潍坳陷、冀中坳陷及黄骅坳陷。这种坳陷之间热演化的差异可能与郯庐断裂的活动有关。构造沉降史的恢复表明：其次级单元莘县凹陷和德州凹陷的构造演化存在差异。正是由于这种构造演化的差异性导致了南部的莘县凹陷古地温梯度整体高于北部的德州凹陷。热演化历史的差异又决定了主要烃源岩生烃史的差别：德州凹陷烃源岩基本未进入成熟生烃状态，而莘县凹陷的主要烃源岩（孔店组和沙河街组四段）大都达到了较成熟或处在生油高峰状态。The thermal history of the Linqing Depression was modeled by using the apatite fission track and vitrinite reflectance data. The thermal gradients decreased with the geological evolution, from 5. 0 - 4. 2℃/100m during sedimentary period of the Kongdian Formation, 3. 4℃/100m at the end of sedimentary period of the Shahejie Formation, 3.2℃/100m at the end of sedimentary period of the Guantao Formation, to 3.0 ℃/100m at present day. However, it increased to 3.5 ℃/100m at the end of sedimentary period of the Dongying Formation, which might be resulted from uplifting and erosion of the Dongying Movement. The thermal regime was relatively lower in the Linqing Depression compared to the Jiyang, Changwei, Central Hebei and Huanghua Depressions in the adjacent areas, which might be related to the activities of the Tan-Lu fault zone. Based on the tectonic subsidence history of some typical wells in the depression, the differentiation of tectonic evolution between the Xinxian Sag in the south and the Dezhou Sag in the north. This differentiation resulted in the difference of thermal evolution and hydrocarbon generation between the both sags. Most part of source rocks in the Dezhou Sag did not enter the maturity situation nowadays. However, the source rocks in the Xinxian Sag in southern part of the Linqing Depression was matured or at the blossom period of oil generation.

关 键 词：热演化历史 磷灰石裂变径迹 镜质体反射率 临清坳陷 

分 类 号：P314[天文地球—固体地球物理学]