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利用大地热流测量、磷灰石裂变径迹及镜质体反射率数据对渤海海域盆地进行了盆地热史恢复 ,结果表明 ,盆地现今热流值为 5 0～ 75 m W/ m2、背景热流值为 6 3.6 m W/ m2 ,而早第三纪沙河街组和东营组沉积时期 (5 0～ 2 5 Ma)古热流值达 6 5～ 90 m W/ m2。构造沉降史分析显示 ,盆地经历了早期 (5 0～ 2 5 Ma)裂谷阶段和后期 (2 5 Ma至今 )热沉降阶段 ,其中裂谷阶段包含了两个裂谷亚旋回 ,热沉降阶段叠加了 12 Ma以来由地幔拆沉及岩石圈冷却诱发的快速均衡沉降。渤海海域盆地较低的现今大地热流值和较高的古热流值 ,以及典型的裂谷型构造沉降样式等支持了渤海海域盆地为板内裂谷盆地的大地构造属性。地层有机质热演化和烃源层生烃状态时空分布研究结果表明 ,渤海海域盆地存在形成大气田的地热条件。
Based on the geothermal heat flow measurements, apatite fission track and vitrinite reflectance data, the thermal history of the basin was reconstructed in the basin of Bohai Sea. The results show that the current heat flow in the basin is 50 ~ 75 mW / m2 and the background heat flux is 6 3.6 mW / m2, while the paleotemperature flow values of the Tertiary Tertiary Shahejie Formation and Dongying Formation during the depositional period (50 ~ 25 Ma) reach 65 ~ 90 mW / m2. The analysis of tectonic subsidence shows that the basin underwent the early (50 ~ 25 Ma) rift and later (25 Ma) thermal subsidence stages, in which the rift phase consists of two rift sub-cycles and the thermal deposition stage is superimposed The rapid equilibrium settlement induced by the mantle delamination and lithospheric cooling since 12 Ma. The lower present-day geothermal flow values and higher paleokraft heat flow values in the Bohai Sea basin and the typical rift-type structural subsidence patterns support the geotectonic properties of the Bohai Sea basin as intraplate rift basins. The results of the temporal and spatial distributions of thermal evolution of organic matter in the stratigraphic and hydrocarbon generation in the source rock show that there are geothermal conditions in the Bohai Sea basin for the formation of large gas fields.