High-resolution bathymetric maps of deep-water sub-circular to circular seafloor depressions offshore of southeastern Florida

High-resolution bathymetric maps were compiled in support of hydrogeologic research conducted by the U.S. Geological Survey Caribbean-Florida Water Science Center in a region offshore of southeastern Florida (Cunningham and others, 2024). Sub-circular to circular seafloor depressions were identified and mapped during 2016-2024 using established and new multibeam-bathymetry of the Miami Terrace, a drowned carbonate platform (Mullins and Neumann, 1979) located on the Florida-Hatteras slope of the southeastern United States continental margin (Uchupi, 1968). Geologic units of the platform exposed at the seafloor range in age from middle Eocene to middle Miocene. The seafloor depressions occur within water depths of about 250 to 663 m, and over an area of approximately 117 km by 26 km. Seafloor depression have diameters that vary between 55 and 1,334 m and depression depths (top to bottom) are up to 170 m. A densely populated band of 189 seafloor depressions was mapped along the margin and upper slope of the Miami Terrace. West of the margin and upper slope, a more sparsely distributed population of 30 seafloor depressions were mapped at the interior platform of the Miami Terrace. This platform is partially overlain by Plio-Quaternary deep-water carbonate slope and drift deposits. A total of 219 images of bathymetric maps and associated shapefiles were constructed from the multibeam data as part of a multidisciplinary effort to link the seafloor depressions to subsurface seismic-reflection data. Images (jpg) are provided for a map showing location and bathymetry of depressions (Location_bathymetry_combined), a large-scale bathymetric map (Bathymetric_map_large), map of locations of multibeam tracklines (Multibeam_tracklines), maps of each depression (Seafloor_depression_[219]), and map of the locations of depressions (Depression_locations). Shapefiles are provided for the bathymetric surface, 5m and 25m bathymetry contours, and depression locations (Shapefiles.zip: Bathy_surface, Bathymetric_contours_5m, Bathymetric_contours_25m, depression locations).

为支撑美国地质调查局加勒比-佛罗里达水文科学中心（U.S. Geological Survey Caribbean-Florida Water Science Center）于佛罗里达东南部近海海域开展的水文地质研究，相关高分辨率水深图（high-resolution bathymetric map）已完成编制（Cunningham等，2024）。2016至2024年间，研究团队依托已有的及新获取的迈阿密台地（Miami Terrace）多波束水深测量（multibeam bathymetry）数据，识别并填绘了近圆形至圆形的海底洼地（seafloor depression）；迈阿密台地是一处淹没碳酸盐台地（drowned carbonate platform，Mullins与Neumann，1979），坐落于美国东南部大陆边缘的佛罗里达-哈特拉斯斜坡（Florida-Hatteras slope，Uchupi，1968）。该台地出露于海底的地质单元（geologic unit）年代跨度为中始新世（middle Eocene）至中中新世（middle Miocene）。海底洼地分布的水深范围约为250至663米，覆盖面积约117千米×26千米。海底洼地的直径介于55至1334米之间，洼地最大深度（顶面至底面）可达170米。沿迈阿密台地的边缘与上斜坡区域，研究人员填绘出一条密集分布的海底洼地带，共计189处。在台地边缘与上斜坡以西的迈阿密台地内部区域，另有分布较为稀疏的30处海底洼地被填绘。该台地局部被上新世-第四纪（Plio-Quaternary）深水碳酸盐斜坡（deep-water carbonate slope）及漂移沉积（drift deposits）所覆盖。为开展多学科研究以关联海底洼地与地下地震反射数据（subsurface seismic-reflection data），研究团队基于多波束数据（multibeam data）共生成了219幅水深图及配套的形状文件（shapefile）。本次提供的JPG格式图像包括：标注海底洼地位置与水深信息的综合图（Location_bathymetry_combined）、大比例尺水深图（Bathymetric_map_large）、多波束测线位置图（Multibeam_tracklines）、单处海底洼地分布图（Seafloor_depression_[219]）以及海底洼地位置分布图（Depression_locations）。配套的形状文件包括：水深表面数据、5米与25米水深等值线数据以及海底洼地位置数据（压缩包Shapefiles.zip内含文件：Bathy_surface、Bathymetric_contours_5m、Bathymetric_contours_25m、depression locations）。