The full range of turbidite bed thickness patterns in submarine lobes: controls and implications
The full range of turbidite bed thickness patterns in submarine lobes: controls and implications
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DOI：
10.1144/jgs2012-056
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发表时间：
2013-01
影响因子：
2.7
通讯作者：
A. Prélat;D. Hodgson
中科院分区：
文献类型：
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作者：
A. Prélat;D. Hodgson
解释露头海底扇系统以及岩心和测井记录中的叶沉积物的一个广泛误用的标准是增厚和/或粗化的向上剖面。西南卡鲁盆地兰斯堡沉积中心的叶状沉积物表明，叶状体内存在各种床层厚度模式。当裂片由其横向广泛的边界表面定义时，其特征是突然的相变化，识别出五种类型的床堆积模式：向上增厚、向上变薄、向上增厚然后向上变薄、向上变薄然后向上变厚以及恒定。突变的边界表面被解释为记录馈线分配通道的撕脱。叶中保存的地层厚度模式反映了较小规模叶元素的内部组织，而不是仅向上增厚模式所暗示的叶范围内的起始和进积。叶瓣的全范围床层厚度模式可用于了解叶瓣元素的堆积、沉积物沉积随时间和空间的演变以及沉降中心的相对运动。
A widely misused criterion to interpret lobe deposits in submarine fan systems at outcrop, and in core and well logs, is a thickening and/or coarsening upward profile. Lobe deposits from the Laingsburg depocentre, SW Karoo Basin, demonstrate that a full range of bed thickness patterns exists within lobes. When lobes are defined by their laterally extensive bounding surfaces that are marked by abrupt facies changes, five types of bed stacking patterns are identified: thickening upward, thinning upward, thickening then thinning upward, thinning then thickening upward, and constant. The abrupt bounding surfaces are interpreted to record avulsion of feeder distributive channels. The stratigraphic bed thickness pattern preserved in a lobe reflects the internal organization of smaller-scale lobe elements, rather than lobe-wide initiation and progradation as implied by a thickening-upward only pattern. The full range of bed thickness patterns in lobes can be used to understand the stacking of lobe elements, the evolution of sediment deposition through time and space, and the relative movement of depocentres.