In the modelling of subsurface fluid flow, faults are dominant features since they can act as fluid pathways, baffles or barriers. Special emphasis is therefore placed in representing them in a numerically efficient manner and the use of lower dimensional domains has become prevalent to simulate higher permeability features like fractures. Such features, however, only represent some of the components of natural fault networks, which can also include rather impermeable fault gouges surrounded by higher permeability damage zones for instance. Here we present a numerical approach to simulate such systems at a large scale, where the thickness of those features makes it advantageous to represent them as discrete rather than continuous domains, using lower dimensional interfaces in a conforming mesh. Benchmarks show excellent agreement with equivalent continuous simulations, regardless of the fault thickness or permeability, both for flow conduits and baffles. This approach can also account for the overprinting of faults with different permeabilities, as well as their dynamic evolution, which we illustrate with an example of trap charging. This work demonstrates the applicability of the approach to simulate fluid flow in faulted environments of various permeabilities and we discuss how those results can easily be extended to account for multi-physical processes.

在地下流体流动的建模中，断层是主要特征，因为断层可以充当流体路径，挡板或屏障。因此，特别强调以数值有效的方式表示它们，并且使用低维域来模拟诸如裂缝的较高渗透率特征已变得普遍。但是，这些特征仅代表自然断层网络的某些组成部分，其中也可能包括相当不可渗透的断层泥，例如被较高的渗透性破坏区所包围。在这里，我们提出了一种数值方法来大规模模拟此类系统，其中这些特征的厚度使得使用一致的网格中的低维界面将它们表示为离散域而不是连续域是有利的。无论断层厚度或渗透率如何，无论是流体导管还是折流板，基准测试都可以与等效的连续模拟很好地吻合。这种方法还可以解决具有不同渗透率的断层的叠印以及它们的动态演化，我们以陷阱充填为例进行说明。这项工作证明了该方法在不同渗透率的断层环境中模拟流体流动的适用性，并且我们讨论了如何轻松地将这些结果扩展为多物理过程的原因。我们以陷阱充电为例进行说明。这项工作证明了该方法在不同渗透率的断层环境中模拟流体流动的适用性，并且我们讨论了如何轻松地将这些结果扩展为多物理过程的原因。我们以陷阱充电为例进行说明。这项工作证明了该方法在不同渗透率的断层环境中模拟流体流动的适用性，并且我们讨论了如何轻松地将这些结果扩展为多物理过程的原因。