Isolated, detached sands provide opportunities for large-volume stratigraphic traps in many deepwater petroleum systems. Here we provide a review of the different types of sandbody detachments based on published data from the modern-day seafloor and recent (generally Quaternary-present), shallow-buried strata. Detachment mechanisms can be classified based on their timing of formation relative to deposition of the detached sandbody as well as their process of formation. Syndepositional detachment mechanisms include flow transformation associated with slope failure (Class 1), turbidity current erosion (Class 2), and contourite deposition (Class 3). Post-depositional detachment is related to subsequent erosive processes and truncation of the pre-existing sandbody, either by submarine channels (Class 4), mass-transport events (Class 5), post-depositional sliding or faulting (Class 6) or bottom currents (Class 7). Examples of each of these mechanisms are identified on the modern seafloor, and show that detached sandbodies can form at different locations along the continental slope and rise (from upper slope to basin floor), and between or within different architectural elements (i.e., canyon, channels and lobes). This variation in formation style results in detached sands of highly variable sizes (tens to hundreds of kilometres) and geometries across and along the depositional profile, which are dependent upon the erosive and/or depositional processes involved, as well as the seafloor topography of the area in question. Whilst modern seafloor systems may not always represent the final stratigraphic architecture in the subsurface, they provide important insights into the development of detached sandbodies and therefore serve as potential analogues for subsurface stratigraphic traps.

孤立的、分离的砂岩为许多深水石油系统中的大体积地层圈闭提供了机会。在这里，我们根据来自现代海底和最近（通常是第四纪至今）浅埋地层的已发表数据，对不同类型的砂体拆离进行了回顾。拆离机制可根据其形成时间相对于拆离砂体的沉积及其形成过程进行分类。同沉积分离机制包括与斜坡破坏（1 类）、浊流侵蚀（2 类）和等高岩沉积（3 类）相关的流动转变。沉积后分离与随后的侵蚀过程和预先存在的砂体的截断有关，无论是通过海底通道（第 4 类）还是大规模运输事件（第 5 类），沉积后滑动或断层（第 6 类）或底部电流（第 7 类）。在现代海底确定了这些机制中的每一个的例子，并表明分离的沙体可以形成在沿着大陆坡和隆起的不同位置（从上坡到盆地底部），以及不同建筑元素之间或内部（即峡谷、通道和瓣）。地层类型的这种变化导致大小（数十至数百公里）和沿沉积剖面的几何形状高度可变的砂岩，这取决于所涉及的侵蚀和/或沉积过程，以及海底地形。有问题的区域。虽然现代海底系统可能并不总是代表地下的最终地层结构，