Abstract In this contribution, high resolution multibeam swath bathymetry and PARASOUND sediment echosounder data are used to describe a region within the distal part of the central Mozambique Channel. The study area marks a transition from abyssal plain to abyssal hill type morphology within the sediment-rich Mozambique Fan and associated with a zone of extension in response to East African Rift System kinematics. Hosted within the abyssal hill lies an east-west orientated, elongate (80 km × 11 km) depression (relief of ca.175 m). Multibeam bathymetry and PARASOUND data show that the region surrounding the depression is variable in geomorphology including rugged irregular seafloor and sediment waves. Low gradient, smooth sea floor dominates the abyssal plain which returns several, distinct, sub-parallel sub bottom echoes. The flanks of the abyssal hill are marked by seafloor undulations likely evidence of bottom-current controlled geomorphology, and mass wasting deposits. The floor of the depression is characterised by hyperbolic echoes commonly associated with very rugged seafloor and basement outcrop with little sediment cover. The present-day geomorphology of the study area is the product of deep-seated ocean circulation and soft sediment deformation superimposed upon the antecedent geological framework, influenced by present-day kinematics of the East African Rift System. Faulting associated with these kinematics is manifest at the seafloor as the elongate steep-flanked depression; the result of an extensional regime expressed across the Mozambique channel from south-southwest to north-northeast. This contribution highlights the local, marine, ramification of a continental-scale largely terrestrial tectonic regime.

中文翻译：

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微板块边界运动学的表面表达：莫桑比克海峡孤立的深海丘陵

摘要 在这篇文章中，高分辨率多波束条带测深仪和 PARASOUND 沉积物回波测深仪数据用于描述莫桑比克中部海峡远端部分的一个区域。该研究区标志着在富含沉积物的莫桑比克扇内从深海平原到深海丘陵类型形态的转变，并与响应东非裂谷系统运动学的延伸带相关联。位于深海山丘内的是一个东西向的细长（80 公里 × 11 公里）洼地（约 175 米的地势）。多波束测深和 PARASOUND 数据表明，洼地周围地区的地貌变化很大，包括崎岖不规则的海底和沉积波。低梯度、平滑的海底占据了深海平原，返回了几个不同的、不同的、亚平行的海底回波。深海山的侧面以海底起伏为标志，这可能是底流控制地貌​​和大量浪费沉积物的证据。凹陷底部的特征是双曲线回波，通常与非常崎岖的海底和基底露头有关，几乎没有沉积物覆盖。研究区现今的地貌是深部海洋环流和软沉积物变形叠加在先行地质格架上的产物，受东非裂谷系现今运动学的影响。与这些运动学相关的断层在海底表现为细长的陡峭侧翼凹陷；横跨莫桑比克海峡从西南偏北到东北偏北的伸展状态的结果。这一贡献突出了当地、海洋、