4-m Grid of the Combined Multibeam Bathymetry Generated from National Oceanic and Atmospheric Administration (NOAA) Surveys H11922, H11995, H11996, H12009, H12010, H12011, H12015, H12023, H12033, H12137, H12139, H12296, H12298, and H12299 Offshore in Rhode Island and Block Island Sounds (RICOMB_4MG

Detailed bathymetric maps of the sea floor in Block Island and Rhode Island Sounds are of great interest to the New York, Rhode Island, and Massachusetts research and management communities because of this area's ecological, recreational, and commercial importance. Geologically interpreted digital terrain models (DTMs) from individual surveys provide important benthic environmental information, yet many applications require a geographically broader perspective. For example, individual surveys are of limited use for the planning and construction of cross-sound infrastructure, such as cables and pipelines, or for the testing of regional circulation models. To address this need, we integrated 14 contiguous multibeam bathymetric DTMs, produced by the National Oceanic and Atmospheric Administration during charting operations, into one dataset that covers much of Block Island Sound and extends eastward across Rhode Island Sound. The new dataset, which covers over 1255 square kilometers, is adjusted to mean lower low water, is gridded to 4-meter resolution, and is provided in UTM Zone 19 NAD 83 and geographic WGS 84 projections. This resolution is adequate for sea-floor feature and process interpretation but is small enough to be queried and manipulated with standard Geographic Information System programs and to allow for future growth. Natural features visible in the grid include boulder lag deposits of winnowed Pleistocene strata, sand-wave fields, and scour depressions that reflect the strength of the oscillating and asymmetric tidal currents and scour by storm-induced waves. Bedform asymmetry allows interpretations of net sediment transport. Together the merged data reveal a larger, more continuous perspective of bathymetric topography than previously available, providing a fundamental framework for research and resource management activities off the Rhode Island coast.

布洛克岛海峡（Block Island Sound）与罗德岛海峡（Rhode Island Sound）的详细海底水深地形图，因该区域兼具生态、休闲与商业价值，受到纽约州、罗德岛州与马萨诸塞州科研及管理学界的高度关注。单次勘测生成的经地质解译数字地形模型（DTMs）虽可提供关键的底栖环境信息，但诸多应用场景需要更广阔的地理视野。例如，单次勘测数据在跨海峡基础设施（如电缆与管线）的规划建设，或是区域环流模型的验证中，应用价值十分有限。为满足这一需求，我们将美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration）在海图测绘作业中生成的14幅连续多波束水深DTMs整合为一套数据集，该数据集覆盖布洛克岛海峡的大部分区域，并向东延伸横跨罗德岛海峡。这套新数据集覆盖面积超过1255平方千米，已校正至平均低潮面，网格分辨率为4米，同时提供通用横轴墨卡托19带NAD 83（UTM Zone 19 NAD 83）与地理坐标系WGS 84两种投影格式。该分辨率既能满足海底地貌与过程解译的需求，又足够轻量化，可通过标准地理信息系统（Geographic Information System, GIS）软件进行查询与处理，同时预留了未来扩容的空间。该网格中可见的自然地貌包括经分选作用改造的更新世地层砾石滞留沉积、沙波场，以及反映振荡不对称潮流强度与风暴浪冲刷作用的冲刷洼地。底形的不对称性可用于推断净沉积物输运方向。整合后的数据集相较于此前的资料，能够展现更广阔、更连续的海底地形地貌全貌，为罗德岛沿岸的科研与资源管理活动提供了基础框架。