Annotated record of the detailed examination of Mn deposits from DSDP Leg 80 (Holes 548, 548A, 550, 551)@en

Deep Sea Drilling Project Leg 80 investigated the structural evolution and depositional history of the Goban Spur and the adjacent Porcupine Abyssal Plain. From the results of DSDP Leg 48, structural relationships and fossil assemblages indicated that the rifting of the Armorican margin created submarine relief of as much as 2000 m. Seafloor spreading began no later than the early Aptian and was accompanied by rapid crustal subsidence in the form of regional downwarping and tilting. Sites 548 to 551 were consequently placed along a transect across the continent/ocean boundary on the sediment-starved Goban Spur in order to further explore this particular structure.深海钻探计划（Deep Sea Drilling Project, DSDP）第80航次（Leg 80）旨在探究戈班海脊（Goban Spur）及其邻近的豪猪深渊平原（Porcupine Abyssal Plain）的构造演化与沉积历史。基于DSDP第48航次的研究成果，构造关系与化石组合均表明，阿摩里卡陆缘（Armorican margin）的裂谷作用曾形成高达2000米的海底地形起伏。海底扩张不晚于阿普第早期（early Aptian）便已启动，同期伴随以区域性坳陷与倾斜为表现形式的地壳快速沉降。为进一步探究该特定构造，研究人员遂在沉积物匮乏的戈班海脊沿横穿陆洋边界（continent/ocean boundary）的剖面布设了548至551号钻探站位。