In the southern oceans, only a few cold-water coral mound sites have so far been reported compared to the extensively surveyed North Atlantic. Here, we document for the first time the widespread occurrence of exposed and buried coral mounds at the northern Argentine margin named Northern Argentine Mound Province (NAMP). The integration of multibeam bathymetry, sediment echosounder, Acoustic Doppler Current Profiler (ADCP), and CTD data allowed the characterisation of its morphosedimentary, stratigraphic, and hydrodynamic setting.

The NAMP, covering at least 2000 km², represents the largest coral mound province in terms of areal extent reported so far and a major site in the southern oceans. The coral mound distribution is directly linked to morphosedimentary features of the regional Contourite Depositional System (CDS) influenced by the Antarctic Intermediate Water (AAIW), the Upper Circumpolar Deep Water (UCDW), and their interface, forming a complex bottom-current-controlled environment here termed Coral-Contourite System. Coral mounds are most abundant in the lower AAIW between 900 and 1050 m, just above the Ewing Terrace Moat, which has been shaped by high-velocity currents associated with the AAIW-UCDW boundary. This clustering appears to be the result of an increased concentration of suspended sediment and food particles, transported along the AAIW-UCDW density gradient and delivered upward by turbulent hydrodynamic processes, which are enhanced by the irregular moat topography. Within the Ewing Terrace Moat, coral mounds are restricted to topographic obstacles, modifying the otherwise highly erosive, destructive hydrodynamic regime and thereby locally creating favourable conditions for coral growth. The low-velocity currents of the UCDW, currently influencing the Ewing Terrace, promote extensive contourite deposition, which has led to a progressive demise and burial of pre-existing mounds. The presence of these buried mounds suggests past mound aggradation 100 to 150 m deeper likely due to a downward shift of the AAIW during glacials as a consequence of sea-level lowering. Overall, the mound formation in the NAMP seems to be mainly controlled by the availability of suspended particles, in combination with a sufficient bottom-current strength, keeping material in suspension while preventing destructive erosion and excessive sedimentation.

Our study highlights (1) the importance of high-energy processes at water-mass boundaries for the delivery of sediment and food particles to corals, (2) the role of the AAIW as a crucial water mass for coral mound development, (3) the variability of mounds in response to glacial-interglacial cycles, and (4) the potential of CDSs in general and the Argentine margin in particular as hotspots for coral mounds and, thus, ideal site for future studies.

与被广泛调查的北大西洋地区相比，迄今为止，在南部海洋中，仅报道了一些冷水珊瑚丘遗址。在这里，我们首次记录了在阿根廷北部边缘称为北部阿根廷土墩省（NAMP）的裸露和埋藏的珊瑚丘的广泛发生。多波束测深法，沉积物回波测深仪，声学多普勒电流剖面仪（ADCP）和CTD数据的集成，可以表征其形态沉积，地层学和流体动力学设置。

NAMP覆盖至少2000 km ²，是迄今为止报道的面积最大的珊瑚丘省，也是南部海洋的主要遗址。珊瑚丘分布与受南极中间水（AAIW），上极极地深水（UCDW）及其界面影响的区域轮廓沉积系统（CDS）的形态沉积特征直接相关，形成了复杂的底流控制这里称为珊瑚轮廓系统的环境。在900-1050 m之间的AAIW下部，恰好在Ewing Terrace护城河上方，是由与AAIW-UCDW边界相关的高速流形成的。这种聚集似乎是由于悬浮沉积物和食物颗粒浓度增加，沿AAIW-UCDW密度梯度运输并通过湍流流体动力学过程向上传递而造成的，而湍流流体动力学过程则由不规则的at沟地形增强了。在Ewing Terrace护城河内，珊瑚丘被限制在地形障碍范围内，从而改变了原本高度侵蚀，破坏性的水动力状态，从而为珊瑚生长创造了有利条件。目前正在影响尤因阶地的UCDW的低流速洋流促使大量的轮廓石沉积，这导致了原有土墩的逐渐灭亡和埋葬。这些埋藏的土墩的存在表明过去的土墩堆积物深了100至150 m，这可能是由于在冰川期间由于海平面降低而导致的AAIW向下移动。总体而言，NAMP中的土丘形成似乎主要受悬浮颗粒的可利用性以及足够的底流强度控制，使材料保持悬浮状态，同时防止破坏性侵蚀和过度沉积。

我们的研究强调（1）水质边界处的高能过程对于向珊瑚输送沉积物和食物颗粒的重要性；（2）AAIW作为珊瑚丘发育的关键水团的作用；（3） （4）CDS的潜力，尤其是阿根廷边缘，尤其是珊瑚丘的热点地区，因此是未来研究的理想场所。