At the Castle Creek study area a superbly exposed continental-slope channel-complex set of the Isaac Formation termed ICC1 crops out. ICC1 is 220 m thick and exposed over 5 km parallel to bedding and consists of four vertically stacked channel complexes—lower channel complex (LC), and three upper channel complexes (termed UC1–UC3). Based on differences in lithological and textural makeup, and stratal trends, two styles of channel fill and stacking pattern are recognized—disorganized stack of bottom-up channel fills (LC, UC1, and UC2), and organized lateral-offset stack of laterally accreting channel fills (UC3). Bottom-up channel fills show an upward and axis-to-margin fining and thinning, and were filled by poorly sorted, density-stratified flows. In contrast, channel fills of UC3 exhibit negligible upward and lateral fining and thinning and were filled by flows enriched in coarse and very coarse sand and were only negligibly stratified in their lower part. Accordingly, the lower, depositionally important part of the flow had a plug-like density profile with limited overspill that caused circulation patterns in channel bends to resemble those in rivers. Notably, the grain-size makeup of late-stage channel fills of UC3 indicates a change in the makeup of the sediment supply, namely grain size and sorting. Note that this systematic upward change in sediment texture and channel type is observed in most (5 of 8) Isaac slope channel-complex sets at the Castle Creek study area. These changes reflect a change from hinterland- to shelf-dominated sediment supply interpreted to be associated with a long-term rise of relative sea level that progressively expanded continental-shelf accommodation and retention of coarse relict and palimpsest sediment. During short-term relative sea-level falls this increasingly voluminous source of coarse, moderately well-sorted siliciclastic and minor carbonate sediment eventually came to dominate the supply of coarse sediment to the shelf edge, and in turn, controlled the character of turbidity currents that remobilized sediment farther down the continental slope and possibly onto the basin floor.

中文翻译：

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沉积物供应对古老被动边缘深海斜坡通道系统地层演化的影响，温德米尔超群，不列颠哥伦比亚省，加拿大

在 Castle Creek 研究区，出露了一组被称为 ICC1 的 Isaac 组的极好暴露的大陆坡河道复合体。ICC1 厚 220 m，与层理平行暴露超过 5 km，由四个垂直叠置的河道复合体——下河道复合体 (LC) 和三个上河道复合体（称为 UC1-UC3）组成。基于岩性和构造组成以及地层趋势的差异，识别出两种类型的河道充填和堆积模式——自下而上河道充填的杂乱叠加（LC、UC1和UC2），以及横向吸积的有组织的横向偏移叠加。通道填充（UC3）。自下而上的通道填充显示出向上和轴向边缘的细化和变薄，并且由分类不良、密度分层的流动填充。相比之下，UC3 的河道充填表现出可忽略不计的向上和横向细化和变薄，并且由富含粗砂和极粗砂的流动填充，并且仅在其下部可忽略不计地分层。因此，流的较低的、沉积重要的部分具有塞状密度分布，溢出有限，导致通道弯道中的循环模式类似于河流中的循环模式。值得注意的是，UC3后期河道充填的粒度构成表明了沉积物供应构成的变化，即粒度和分选。请注意，在 Castle Creek 研究区的大多数（8 个中的 5 个）Isaac 斜坡通道复合体组中观察到沉积物质地和通道类型的这种系统性向上变化。这些变化反映了从腹地到大陆架主导的沉积物供应的变化，这被解释为与相对海平面的长期上升有关，这种上升逐渐扩大了大陆架的容纳空间，并保留了粗糙的残留物和最丰富的沉积物。在短期相对海平面下降期间，这种数量越来越多的粗粒、中等分选的硅质碎屑和少量碳酸盐沉积物最终主导了向陆架边缘供应粗粒沉积物，进而控制了浊流的特征，将沉积物重新移动到更远的大陆坡下方，并可能进入盆地底部。