Uranium-series dating and mound aggradation rates obtained from the Mauritanian coral mound province

The largest coherent cold-water coral (CWC) mound province in the Atlantic Ocean exists along the Mauritanian margin, where up to 100 m high mounds extend over a distance of ~400 km, arranged in two slope-parallel chains in 400-550 m water depth. Additionally, CWCs are present in the numerous submarine canyons with isolated coral mounds being developed on some canyon flanks. Seventy-seven Uranium-series coral ages were assessed to elucidate the timing of CWC colonisation and coral mound development along the Mauritanian margin for the last ~120,000 years. Our results show that CWCs were present on the mounds during the Last Interglacial, though in low numbers corresponding to coral mound aggradation rates of 16 cm kyr**-1. Most prolific periods for CWC growth are identified for the last glacial and deglaciation, resulting in enhanced mound aggradation (>1000 cm kyr**-1), before mound formation stagnated along the entire margin with the onset of the Holocene. […]

大西洋海域中，沿毛里塔尼亚海岸线存在最大的连续冷水珊瑚（CWC）丘省，其中高达100米的丘状地形延伸约400公里，沿400-550米水深处的斜坡平行链状排列。此外，CWC珊瑚还存在于众多海底峡谷中，部分峡谷两侧形成了孤立的珊瑚丘。通过对77个铀系珊瑚年龄的评估，阐明了在过去约12万年内，毛里塔尼亚海岸线CWC的殖民化和珊瑚丘发育的时间节点。研究结果表明，在最后一个间冰期期间，CWC珊瑚已在丘状地形上存在，但数量较少，与珊瑚丘沉积速率16 cm/kyr**-1相对应。CWC生长最旺盛的时期被确定为最后的冰期和冰川消退期，导致丘状地形沉积速率显著增加（>1000 cm/kyr**-1），随后随着全新世的到来，整个海岸线的丘状地形形成趋于停滞。