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作者通过密西西比现代被动边缘海底扇(DSDP96航次)与古活动边缘海底扇(例如西班牙的古新统 Hecho 群)的比较,揭示了两者在浊积组合(Mutti和 Ricci Lucchi 方案)和下部扇区地震特性上的重大差异。密西西比扇的下海底扇(外扇)由水道相(相 B 和 F)和无水道相(相 C?和 D)组成,而古海底扇则以向上增厚的无水道沉积朵叶体(lobe)相(相 C 和 D)为特征。密西西比海底扇下部扇区地震剖面上缺乏双向下超丘状反射,也表明其不存在沉积朵叶体。密西西比下海底扇的连续地震反射可能代表“席状砂”,但并非具岗丘状特征的真的沉积朵叶体。现代被动边缘海底扇的大面积渠化,看来是因坡降缓和低砂泥比沉积物搬运而发育起来的一个主要的汊道曲流体系侧向迁移的结果。反之,活动边缘海底扇中的水道则短而曲度低,属陡坡降及高砂泥比沉积物搬运的产物。仅仅根据古活动边缘海底扇推演出来的浊积相组合方案,由于浊积相及其组合在空间分布上的差异,必须附带若干条件才能用于壮年被运动边缘海底扇。
Comparisons between the DSCP96 voyage of the Mississippi modern passive edge seafloor fan and the paleo-active edge seafloor fan (eg, the ancient Herat group of Spain) reveal that both the turbidimetric combination (Mutti and Ricci Lucchi scheme) and the lower sector Seismic characteristics of the major differences. The lower sea fan (fan) of the Mississippi fan consists of the water channel facies (facies B and F) and the waterless facies (facies C and D), whereas the paleo-sea fan deposits the lobe ) Phases (phases C and D). There is a lack of bi-directional downhill dome-shaped reflections on the Seismic Sections of the lower Mississippi submarine fan, which also indicates that there is no sedimentation of the lobes. The continuous seismic reflection of the undersea fan in the Mississippi may represent “sand-like sand” but not a true sedimentary leaf body with hill-mound features. The large area canalization of the modern passive margin submarine fan appears to be the result of a lateral migration of a major meandering meander system developed as a result of the slowing of the slope and the transport of low sand and sand over the sediments. On the contrary, the water channel in the active margin sea fan is short and the curvature is low, which is caused by the steep slope and the high sandy sand than the sediment transport. According to the combination scheme of turbidimetric sediment derived from the submarine fan of paleo-active edge, due to the difference of the spatial distribution of turbidite phase and its assemblage, several conditions must be attached for the submarine fan of the moving edge.