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通过典型碳酸盐型油气田的野外调查研究和对未成熟碳酸盐生油岩在外加温、外加压条件下所作的生烃一排烃模拟实验结果，获得下列新的认识：（１）碳酸盐烃源岩排烃的驱动力主要不是来自地层的压实作用，而是由于生烃过程中分子体积膨胀所产生的内应力（即生烃增压）。该应力与周围环境形成潜在的压力梯度，这是排驱动力的内在因素。但是单凭此因素尚不足以造成排烃，只有当后来烃源层受到外力作用（如导致微裂隙产生的区域性构造活动、造成溶蚀交代出现缝缝洞洞的地下水活动等）生成裂隙空间，并在源岩与裂隙间出现真正的压差时，才引发烃源层中积蓄的应力释放，从而造成排烃。因此、区域性的外力作用是排烃的控制因素。（２）碳酸盐烃源岩中生烃时间甚早，一般在Ｒ＿０为０．４５％左右时就开始生成低熟原油。但由于碳酸岩岩石粒间孔径甚小，虽有低熟油生成，却不能象泥质烃源岩那样在其烃浓度超过最低石油运移饱和度时就可排烃。事实证明，无论生烃量多大，只要碳酸盐烃源岩中不出现有效的通道，排烃作用可能永远不会进行。因此，当碳酸盐烃源岩中油气生成之后，裂隙发生的时间就成为决定碳酸盐烃源岩排烃时间的基本因素。（３）碳酸盐烃源岩中烃类初次运移基本上是以全烃相进行的，这与碳酸盐岩在后?
Based on the field investigation of typical carbonate oil and gas fields and the simulation results of hydrocarbon generation and expulsion of hydrocarbons in immature carbonate source rocks under external heating and external pressure, the following new understandings are obtained: (1) The driving force of hydrocarbon expulsion from carbonate source rocks is not mainly from the compaction of the formation but from the internal stress (ie, hydrocarbon generation and pressurization) generated by the volume expansion of the molecules during hydrocarbon generation. This stress creates a potential pressure gradient with the surrounding environment, which is an inherent factor in driving force. However, this factor alone is not enough to cause hydrocarbon expulsion. Only when the hydrocarbon source is subsequently subjected to external forces (such as regional tectonic activity resulting in micro-fissures and groundwater activities resulting in erratic dissolution of fractured fissures, etc.) create fissure space, And when the true pressure difference between the source rocks and fractures occurs, the stress accumulated in the hydrocarbon source layer will be released, resulting in hydrocarbon expulsion. Therefore, the regional external force is the controlling factor of hydrocarbon expulsion. (2) Carbonate source rocks have a very early hydrocarbon generation time, and generally begin to generate low-mature crude oil when the R_0 is about 0.45%. However, due to the small intergranular pore size of carbonatite rocks, low-maturity oil generation can not displace hydrocarbons when their hydrocarbon concentration exceeds the minimum oil migration saturation as that of shale source rocks. It turns out that, no matter how large hydrocarbon generation, as long as there is no effective channel in carbonate source rocks, hydrocarbon expulsion may never be carried out. Therefore, when hydrocarbon generation occurs in the carbonate source rock, the time of occurrence of the fracture becomes the basic factor that determines the hydrocarbon expulsion time of the carbonate source rock. (3) The primary hydrocarbon migration in carbonate source rocks is basically in hydrocarbon phase, which is related to carbonate rocks?