Fault zones can often display a complex internal structure associated with antithetic faults, branch and tip points, bed rotations, bed-parallel slip surfaces, and subordinate synthetic faults. We explore how these structural complexities may affect the development of fault-related fractures as displacement accumulates. We analysed in detail an incipient fault zone within well-bedded, shallow-water carbonates of the southern Apennines thrust belt (Italy). The fault zone crops out with quasi-complete exposure at a reservoir scale on an inaccessible sub-vertical cliff face, and fault and fracture mapping were carried out on a 3D virtual outcrop model of the exposure built for this study using photogrammetry. Comparing the structure of the fault zone and the density of 9444 mapped fractures allowed us to unravel their spatial relationships. Our results show that the areas of denser fractures coincide with: (i) rock volumes bounded by antithetic faults developed within the fault zone, (ii) branch points between these antithetic faults and fault zone-bounding fault segments, (iii) fault zone-bounding fault segments associated with significant displacement gradients, and (iv) relay zones between subordinate synthetic faults. These findings may aid locating sub-seismic resolution volumes of dense fracturing and associated enhanced permeability within faulted reservoirs.

断层带通常表现出与对立断层、分支和尖端点、地层旋转、与地层平行的滑移面和从属合成断层相关的复杂内部结构。我们探讨了随着位移的积累，这些结构的复杂性如何影响断层相关裂缝的发展。我们详细分析了亚平宁山脉南部逆冲带（意大利）的层状浅水碳酸盐岩内的一个初期断裂带。断层带在难以接近的亚垂直悬崖面上以水库规模以准完全暴露的方式出现，并且断层和裂缝映射是使用摄影测量在为本研究建立的暴露的 3D 虚拟露头模型上进行的。比较断层带的结构和 9444 条映射裂缝的密度，使我们能够解开它们的空间关系。我们的结果表明，较密的裂缝区域与：(i) 以断层带内发育的对立断层为界的岩石体积，(ii) 这些对立断层和断层带边界断层段之间的分支点，(iii) 断层带-与显着位移梯度相关的边界断层段，以及 (iv) 次级合成断层之间的中继带。这些发现可能有助于在断层油藏内定位致密压裂和相关的增强渗透率的亚地震分辨率体积。(iv) 从属合成故障之间的中继区。这些发现可能有助于在断层油藏内定位致密压裂和相关的增强渗透率的亚地震分辨率体积。(iv) 从属合成故障之间的中继区。这些发现可能有助于在断层油藏内定位致密压裂和相关的增强渗透率的亚地震分辨率体积。