Igneous intrusions in sedimentary basins can influence basin-scale fluid flow and petroleum systems in various ways. They may act as barriers, preferential pathways or even reservoirs for fluids. The fracture networks of intrusions usually represent the main control of their hydraulic properties. However, our understanding of different fracturing mechanisms and their quantitative effect on fracture network properties remains limited, and good field examples are sparse. Here, we present a comprehensive field study from the Neuquén Basin, Argentina, using a reservoir-scale outcrop of a sill complex emplaced in organic-rich shale, which constitutes a direct analogue of oil-producing fractured igneous reservoirs. We provide field evidence of various fracturing mechanisms affecting the fracture network, including cooling joints, bituminous dykes, hydrothermal veins, and tectonic faults. Using high-resolution digital fracture network quantification, we then tie these fracture mechanisms to spatial variations of fracture orientation, intensity and connectivity. Our results indicate that all observed fracture types are involved in hydrocarbon migration and/or storage. Bitumen of very high thermal grade within the intrusions implies migration of hydrocarbons into the sills in a destructive high-temperature environment. Importantly, bitumen dykes and faults locally alter the fracture network, creating zones of strongly increased fracture intensity and connectivity and therefore improved reservoir properties.

沉积盆地中的火成岩侵入体可以以各种方式影响盆地尺度的流体流动和石油系统。它们可以作为流体的屏障、优先通道甚至储库。侵入体的裂缝网络通常代表其水力特性的主要控制。然而，我们对不同压裂机制及其对裂缝网络性质的定量影响的理解仍然有限，良好的现场例子很少。在这里，我们展示了来自阿根廷内乌肯盆地的综合实地研究，使用位于富含有机质页岩中的基岩复合体的储层规模露头，它构成了产油裂缝火成岩储层的直接类似物。我们提供影响裂缝网络的各种压裂机制的现场证据，包括冷却接头、沥青堤、热液脉和构造断层。使用高分辨率数字裂缝网络量化，然后我们将这些裂缝机制与裂缝方向、强度和连通性的空间变化联系起来。我们的结果表明所有观察到的裂缝类型都涉及油气运移和/或储存。侵入体中具有非常高的热等级的沥青意味着在破坏性的高温环境中碳氢化合物会迁移到窗台中。重要的是，沥青岩脉和断层局部改变了裂缝网络，形成了裂缝强度和连通性显着增加的区域，从而改善了储层性质。强度和连​​通性。我们的结果表明所有观察到的裂缝类型都涉及油气运移和/或储存。侵入体中具有非常高的热等级的沥青意味着在破坏性的高温环境中碳氢化合物会迁移到窗台中。重要的是，沥青岩脉和断层局部改变了裂缝网络，形成了裂缝强度和连通性显着增加的区域，从而改善了储层性质。强度和连​​通性。我们的结果表明，所有观察到的裂缝类型都涉及油气运移和/或储存。侵入体中具有非常高的热等级的沥青意味着在破坏性的高温环境中碳氢化合物会迁移到窗台中。重要的是，沥青岩脉和断层局部改变了裂缝网络，形成了裂缝强度和连通性显着增加的区域，从而改善了储层性质。