Portion of the 1-meter (m) contours in quadrangle 5 of the Stellwagen Bank Survey Area offshore of Boston, Massachusetts based on bathymetry data collected by the U.S. Geological Survey from 1994-1996

The U.S. Geological Survey (USGS), in cooperation with the National Marine Sanctuary Program of the National Oceanic and Atmospheric Administration (NOAA), has conducted seabed mapping and related research in the Stellwagen Bank National Marine Sanctuary (SBNMS) region since 1993. The interpretive datasets and source information presented here are for quadrangle 5, which is one of 18 similarly sized segments of the 3,700 square kilometer (km2) SBNMS region. The seabed of the SBNMS region is a glaciated terrain that is topographically and texturally diverse. Quadrangle 5 includes the shallow, rippled, coarse-grained sandy crest and upper eastern and western flanks of southern Stellwagen Bank, its fine-grained sandy lower western flank, and the muddy seabed in Stellwagen Basin. Water depths range from <25 m on the bank crest to ~100 m in the basin. The data presented here for quadrangle 5 are the foundation for Scientific Investigations Map 3515 (Valentine and Cross, 2024), which presents maps of seabed topography, ruggedness, backscatter intensity, distribution of geologic substrates, sediment mobility, distribution of fine- and coarse-grained sand, and substrate mud content. The maps of quadrangle 5 show the distribution of substrates across the southern part of Stellwagen Bank and the adjacent basins. Bathymetric and seabed backscatter imagery, photographs, video, and grain-size analyses were used to create the geologic interpretations presented here and have been reprocessed and released in segments to supports these interpretations. For the quadrangle 5 interpretations, data from 729 stations were analyzed, including 620 sediment samples. The seabed geology map of quadrangle 5 shows the distribution of 20 substrate types ranging from boulder ridges to mobile and rippled sand, to mud. Substrate types are defined or inferred through sediment grain-size composition, surface morphology, sediment layering, the mobility or immobility of substrate surfaces, and water depth range. Scientific Investigations Map 3515 portrays the major geological elements (substrates, topographic features, processes) of environments within quadrangle 5. It is intended to be a basis for the study of sediment transport processes that affect a shallow, offshore bank, for the study of the ecological requirements of invertebrate and vertebrate species that use these substrates, and to support seabed management in the region.

美国地质调查局（U.S. Geological Survey, USGS）与美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）下属的国家海洋保护区计划合作，自1993年起便在斯特尔瓦根银行国家海洋保护区（Stellwagen Bank National Marine Sanctuary, SBNMS）区域开展海底测绘及相关研究工作。本次展示的解释性数据集与源信息均来自5号测区，该区域是占地3700平方千米的SBNMS区域的18个同等规模分段之一。

SBNMS区域的海底为冰川作用塑造的地貌，地形与质地均兼具多样性。5号测区涵盖斯特尔瓦根银行南部的浅滩、具波纹状粗糙砂质海脊及其东西两侧上部坡地，其西侧下部为细粒砂质区域，以及斯特尔瓦根盆地的泥质海底。该区域水深范围从海脊顶部的小于25米，至盆地内的约100米不等。

本次发布的5号测区数据是《科学调查地图集3515》（Valentine与Cross，2024）的基础数据，该图集包含海底地形、地形粗糙度、反向散射强度、地质基质分布、沉积物活动性、粗细砂分布以及基质泥质含量等专题地图。5号测区的专题地图展示了斯特尔瓦根银行南部及相邻盆地的基质分布情况。

研究团队通过水深测量与海底反向散射影像、照片、视频以及粒度分析，完成了本次展示的地质解译，并对相关数据进行了分段重新处理与发布，以支撑上述解译工作。针对5号测区的解译工作，团队共分析了729个测站的数据，其中包含620个沉积物样品。

5号测区的海底地质图展示了20种基质类型的分布，涵盖从砾石脊、活动波纹砂至泥质的各类基质。基质类型通过沉积物粒度组成、表面形貌、沉积物层理、基质表面活动性以及水深范围进行定义或推断。

《科学调查地图集3515》呈现了5号测区所在环境内的主要地质要素（基质、地形特征、作用过程），其旨在作为研究影响浅海离岸沙洲的沉积物搬运过程、探究依托此类基质生存的无脊椎动物与脊椎动物物种的生态需求的基础，同时为该区域的海底管理提供支撑。