Investigation of expulsion and primary migration usually suffers from inadequate methodologies failing to simulate natural conditions prevailing during oil and gas formation. The Expulsinator device provides a unique methodology to study these processes under near-natural conditions of pressure as well as near-natural constellation of source rock and reservoir. Eight source rocks, differing in lithology and kerogen type ((type-I, type-II, type-IIS and type-III) were treated with the Expulsinator to simulate oil and gas generation and expulsion with increasing subsidence. A standardised pressure and temperature program covering the main oil window was used, simulating pressure regimes, corresponding to 2000 m, 2500 m and 3000 m of depth at pyrolysis temperatures of 300 °C, 330 °C and 360 °C, respectively. The semi-open setup of the Expulsinator enabled the sampling of the products generated during the experiment, providing unique generation/expulsion profiles for each source rock. Expulsinator treatment by continuous withdrawal prevents the formation of condensation products and solid pyrobitumen, which are common artefacts of closed-mode pyrolysis and misleading in maturity assessment. In particular, the Rock-Eval T_max-value is affected by pyrobitumen formation. The oil and gas generation/expulsion profiles show large differences between the source rocks, controlled by the organic matter composition, as well as the lithological characteristics. Earliest onset of hydrocarbon generation and expulsion was observed for source rocks containing kerogen type-III, followed by sulfur-rich type-IIS and type-II. Lacustrine type-I source rocks showed the latest onset of hydrocarbon generation. Lithology was an important factor for the observed generation/expulsion behaviour under the experimental pressure and temperature conditions. Competent lithologies with a high degree of cementation and/or low permeability showed limited expulsion efficiency; in contrast, expulsion was enhanced by pressure-induced “squeezing” effects in ductile lithologies. A highly permeable but competent sample reached only moderate expulsion efficiency due to low “squeezing” response upon burial pressure.

对驱逐和主要迁徙的调查通常受到方法论不足的困扰，这些方法论未能模拟油气形成过程中普遍存在的自然条件。Expulsinator设备提供了一种独特的方法来研究在近乎自然的压力条件下以及烃源岩和储层的近乎自然星座的情况下的这些过程。用驱除剂处理了八种烃源岩，它们具有不同的岩性和干酪根类型（（I型，II型，IIS型和III型），以模拟随着沉降增加而产生和驱出的油气。标准化的压力和温度使用涵盖主油窗的程序，模拟在300°C，330°C和360°C的热解温度下分别对应于2000 m，2500 m和3000 m深度的压力范围。驱除器的半开放式设置可对实验过程中产生的产物进行采样，从而为每种烃源岩提供独特的生成/驱除特征。通过连续撤除的驱除剂处理可防止形成缩合产物和固态焦油，这是闭式热解的常见假象，在成熟度评估中具有误导性。特别是Rock-Eval T_最大限度-值受焦炉子形成的影响。油气生成/驱替剖面显示，烃源岩之间的差异很大，受有机质成分控制，并且具有岩性特征。观察到最早含III型干酪根的烃源岩生烃和排烃的开始，其次是富含硫的IIS型和II型烃源岩。I型Lacustrine烃源岩显示出碳氢化合物的最新生成。岩性是在实验压力和温度条件下观察到的生成/排出行为的重要因素。具有高胶结度和/或低渗透率的岩性表现出有限的驱替效率。相反，在延性岩性中压力引起的“挤压”效应增强了驱逐作用。