ABSTRACT

This contribution reports on the field mapping of 9 exceptionally well-exposed channel-levée complexes from Taza–Guercif Basin (NE Morocco), belonging to the Late Miocene Tachrift turbidite system. Separated from each another by hemipelagic marlstones, the mapped channel-levée complexes exhibit thicknesses in the range of 5–25 m. Four main sedimentary facies associations were mapped, including channel-fill sandstones, levée thin-bedded heterolithics, chaotic mass transport deposits, and hemipelagic marlstones. In addition, two end-member styles of channel-fills spatial stacking were recognized, reflecting different modes of channel belt development and/or location along the slope profile, namely: (a) a lateral-migration pattern, resulting from lateral migration of high-sinuosity levéed channel belts, as opposed to (b) a vertically stacked pattern, interpreted to reflect the vertical aggradation of levéed channel belts with a relatively low sinuosity. The geological map accompanying this contribution provides the basis for more in-depth sedimentological investigations on the channels of the Tachrift turbidite system.

摘要

该文稿报告了来自塔扎格列夫盆地（摩洛哥东北部）的9个异常暴露的河道-河岸复合体的现场测绘，该复合体属于中新世Tachrift晚浊体系统。被半潜泥岩相互分隔，映射的河道-堤坝复合体的厚度在5-25 m范围内。绘制了四个主要的沉积相组合，包括河道填充砂岩，左旋薄层异质岩，混乱的大规模输运沉积物和半潜质的泥岩。此外，人们认识到通道填充空间堆叠的两种末端构件样式，反映了通道带发展和/或沿斜坡剖面的位置的不同模式，即：（a）侧向迁移模式，这是由于高边向迁移引起的。 -弯曲度升高的河道带，与（b）垂直堆叠的模式相反，可以解释为反映了波纹度较低的带状河道带的垂直沉降。伴随着这一贡献的地质图为在Tachrift浊质系统通道上进行更深入的沉积学研究提供了基础。