This map shows some major features of the Gulf of Maine region based on existing data. The Gulf of Maine Mapping Initiative intends to produce detailed maps of the undersea landscape, including seafloor topography, geology, and habitats. Recent technological advances allow seafloor mapping on an unprecedented scale. Mapping the Gulf of Maine seafloor is one of the essential first steps for achieving effective management of trawling, dredging, aquaculture, mining, fiber-optic and electric power cables, oil and gas pipelines, wind farms, and other activities that can affect seabed habitats.

Only parts of the Gulf of Maine have been mapped in sufficient detail for ocean management. The Gulf of Maine Mapping Initiative is a multi-year project to secure funding and conduct a comprehensive mapping program of areas not already covered by high-resolution bathymetric surveys. The goal is to provide seafloor images, maps, and surveys that are fundamental for resource management, planning, and many commercial activities.

Interactive map (HTML)
Small version for Web, email, and PowerPoint: 72 dpi, 10x10 inches (JPEG, 496 KB)
Medium version for printing: 300 dpi, 10x10 inches (JPEG, 1 MB)
Large version for printing: 300 dpi, 25x25 inches (JPEG, 3.9 MB)

Map with list of survey areas and data providers (Word, 762 MB)

Seafloor topography and backscatter maps are derived from acoustic (multibeam sonar) surveys. Geology and habitat maps are produced by analyzing data from acoustic surveys and groundtruthing.

This image shows the contours of the seafloor at Stellwagen Bank in Massachusetts Bay based on data from multibeam sonar. The colors indicate hardness and roughness of the substrate. Red and orange indicate coarse sand or rock. Green denotes sand or muddy sand. Blue means mud or sandy mud. Data from multibeam surveys can be combined with data from biological sampling to produce habitat maps.

Between 1994 and 1996, the National Marine Sanctuary Program worked with the U.S. Geological Survey to map Stellwagen Bank National Marine Sanctuary and portions of western Massachusetts Bay. Scientists collected multibeam sonar data on bathymetry and substrate, which they ground-truthed with video, photography, and sediment samples. The maps cover 3,900 square kilometers and provide important information for management and research activities. When a private company needed to place a fiber-optic cable through the Sanctuary in 2000, they used the maps to route it across areas of soft sediment, avoiding hard gravel bottom where the cable could not be buried for its protection. Normally, extensive bottom sampling would have been required, increasing both project costs and ecological impacts on seafloor habitats.