ROV Tracklines from 2001 in the Pulley Ridge are in the Gulf of Mexico based on 5-min navigation

Pulley Ridge is a series of drowned barrier islands that extends almost 200 km in 60-100 m water depths. This drowned ridge is located on the Florida Platform in the southeastern Gulf of Mexico about 250 km west of Cape Sable, Florida. This barrier island chain formed during the initial stage of the Holocene marine transgression. These islands were then submerged and left abandoned near the outer edge of the Florida Platform. The southern portion of Pulley Ridge hosts zooxanthellate scleractinian corals, green, red and brown macro algae, and a mix of deep and typically shallow-water tropical fishes. This reef community is in unusually deep water, and its extent and the controls on its distribution were unknown. To address these questions scientists from the U.S. Geological Survey Coastal and Marine Geology Program in cooperation with scientists from the University of South Florida Department of Marine Sciences have completed a detailed mapping of the southernmost 35 km of Pulley Ridge. The area was mapped using multibeam bathymetry, sidescan-sonar imagery, and high-resolution seismic-reflection profiling to define the geologic framework on which the reef is established. Submersible dives, remotely operated vehicle (ROV) transects, and transects of bottom photographs and video were collected to identify the corals and to map their distribution. This extensive suite of data has been compiled and preliminary analysis of the data suggests that the reefs are not tied to the ridge system, but instead are more broadly distributed. Whether reef distribution is controlled by oceanographic conditions or by subtle differences in the substrate that overlies the barrier island system is unclear, and are topics of continued research.普利岭（Pulley Ridge）是一片绵延近200公里、分布于水深60至100米海域的被淹没障壁岛群（barrier islands）。该淹没脊岭坐落于墨西哥湾东南部的佛罗里达台地（Florida Platform）之上，距离佛罗里达州萨布尔角（Cape Sable）以西约250公里。该障壁岛链形成于全新世海侵（Holocene marine transgression）初期阶段，随后这些岛屿被淹没并被遗弃在佛罗里达台地的外缘附近。普利岭的南部区域栖息着虫黄藻共生造礁石珊瑚（zooxanthellate scleractinian corals）、绿藻、红藻与褐藻等大型藻类（macro algae），以及深浅水热带鱼类的混合群落。该礁体群落所处水深异乎寻常，其分布范围与控制其分布的核心因素此前尚不明确。为解答这些科学问题，美国地质调查局（U.S. Geological Survey）海岸与海洋地质项目组的科研人员，与南佛罗里达大学（University of South Florida）海洋科学系的学者展开合作，完成了普利岭最南端35公里区域的详细测绘工作。研究团队采用多波束测深（multibeam bathymetry）、侧扫声呐成像（sidescan-sonar imagery）与高分辨率地震反射剖面测量（high-resolution seismic-reflection profiling）技术，明确了礁体发育的地质基底框架。此外，通过载人潜水器下潜、遥控无人潜水器（remotely operated vehicle，ROV）断面勘测，以及海底照片与视频采样工作，科研人员完成了珊瑚类群的识别与分布制图。这套覆盖全面的数据集已完成整合，初步数据分析显示，礁体分布并未与该脊岭系统绑定，而是呈现更为广泛的分布格局。目前尚不清楚礁体分布究竟受海洋水文条件控制，还是受障壁岛系统上覆基底的细微差异影响，相关问题仍是当前持续研究的核心课题。