随着油气勘探理论的发展和技术的进步,超深层已经成为油气勘探的重要领域.受地层温度、压力、生烃/充注/成藏时间、储层岩石矿物学特征以及构造作用等因素的影响和控制,超深层油气保存条件的评价参数与中浅层的不同.温度控制超深层烃类相态转化,压力控制超深层盖层超压破裂,烃类组分、成藏时间以及盖层物性控制超深层油气的扩散损失,储层岩石矿物学特征影响烃类-流体-岩石相互作用及化学反应对烃类的破坏,构造作用控制深大断裂的形成演化,进而控制烃类的垂向运移与散失.在对超深层油气保存的影响与控制因素进行分析的基础上,提出应从地下烃类的物理散失和化学损耗2个方面开展超深层油气保存条件评价.

With the development of petroleum exploration theories and advances in technology, ultra-deep sequences in sedimentary basins have become one of the important fields of petroleum exploration. According to the results of the evaluation of oil and gas preservation conditions in ultra-deep oil and gas exploration, it could be concluded that the parameter indexes for the evaluation of ultra-deep oil and gas preservation are different from those in middle and shallow sequences. The preservation of the ultra-deep oil and gas probably is mainly controlled by the factors such as formation temperature, pressure, hydrocarbon generation/filling time, reservoir rock mineralogy characteristics and tectonic events. In the ultra-deep sequences, the hydrocarbon phase state transformation is generally controlled by temperature, the cap rock overpressure fracture is controlled by pressure, the diffusion loss is controlled by the accumulation time, hydrocarbon components and cap rock physical properties, hydrocarbon destruction owing to chemical reactions is controlled by reservoir rock mineralogy characteristics and hydrocarbon-fluid-rock interaction. The tectonic event controls the evolution of deep faults and therefore the vertical migration and loss of hydrocarbon. In short, the evaluation of ultra-deep oil and gas preservation should be carried out from two aspects: physical loss and chemical destruction.