济阳坳陷新生代主要生油岩系底界面温度分布  

Distribution of Temperature at the Bottom of Cenozoic Principal Source Rocks in Jiyang Depression

作　　者：龚育龄[1] 王良书[2] 刘绍文[3] 

机构地区：[1]东华理工大学地球物理系,江西抚州344000 [2]南京大学地球科学系,江苏南京210093 [3]南京大学地理与海洋科学学院,江苏南京210093

出　　处：《大地构造与成矿学》2009年第3期427-431,共5页Geotectonica et Metallogenia

基　　金：国家基础研究发展规划项目(批准号:G1999043302);国际合作项目(批准号:2007DFA20790)资助

摘　　要：依据济阳坳陷千余口测温井的地温梯度数据和地层岩性描述、分层数据以及钻井资料,计算了该区各生油岩系底界面的温度。统计结果表明:济阳坳陷大部分地带沙河街组地层底界面温度介于90～150℃之间,目前仍具有大量生油的温度条件,而在一些凸起地区和斜坡地带,该地层组段温度普遍小于90℃,未能达到生油的温度指标;孔店组地层也具有一定的生油温度条件。研究表明,地层温度与地层界面埋深密切相关,温度随界面埋深的增大而升高,沉积厚度大的凹陷带界面温度大于沉积厚度小的凸起区或斜坡地带,说明地层界面埋深是决定地温高低的主要控制因素,而地温梯度对地层界面温度的影响相对较小。With the development of deep layer gas prospecting in the Jiyang depression, many new well temperature data are increasing. These data surveyed from the depth more than 3500 meters provide credible basic information to assess the deeper source rocks in particular to assess the strata temperature of the Paleogene from the Kongdian formation to the Shahejie formation. In this paper, based on temperature data, strata lithology description, stratifi- cation data and radioactivity heat generation rate of rocks survey from thousands of wells in the Jiyang depression, the current temperatures on the bottom surface of above-mentioned strata were calculated using 1D steady heat exchange formula. The results show that the temperature at the bottom of the Shahejie formation in most zones of the basin changes from 90 to 150℃ , satisfying the condition for oil generation, while it is less than 90℃ for the same formation in areas of uplifts or slopes, not enough for oil generation. The Kongdian formation is possible for oil gen- eration in temperature to some extent. It is also found that the temperature shows a close relationship with the buried depth of the formation, and increases with the increasing depth. The temperature in the sags where the sediments are relatively thick is higher than that in the uplifts and slopes with relatively thin thickness, indicating that the depth of the formation is the key for controlling its temperature, and the influence of the geo-temperature gradient is relatively smaller.

关 键 词：济阳坳陷 地温梯度 地层底界面 生油岩系 油气液态窗 

分 类 号：P593[天文地球—地球化学]