The data in this layer are from an unpublished report produced by the Bigelow Laboratory. The source project was conducted primarily to examine contaminant distributions, but also produced sediment textural data. The data presented in this layer were not part of the Gulf of Maine Contaminated Sediments Database.

Surficial geologic maps play and important role in understanding the present sea floor and the processes that shape it. Between 1984 and 1991, over 1,700 bottom sample stations were occupied in the northwestern Gulf of Maine. Although the data were originally collected for a variety of research projects, contracts, and graduate student theses, they were eventually compiled as part of a Maine Geological Survey and University of Maine program to map the inner continental shelf of this region.

The sediment data presented in this data layer were from a geochemical study sited in Great Bay Estuary, New Hampshire. The analog data were originally converted into digital form for inclusion in a Gulf of Maine Contaminated Sediments Database.

The sediment data presented in this data layer were from a geochemical study sited in Great Bay Estuary, New Hampshire. The analog data were originally converted into digital form for inclusion in a Gulf of Maine Contaminated Sediments Database.

The sediment data contained in this set were produced as part of the site description and monitoring phases of an aquaculture demonstration project. The site is located off the coast of New Hampshire in the Gulf of Maine.

The data in this layer are from a number of published and unpublished sets produced by the Bigelow Laboratory. The source projects were conducted primarily to examine contaminant (e.g. trace metals, PAHs) distributions, but also produced sediment textural data. The data were originally converted into digital format for inclusion in the Gulf of Maine Contaminated Sediments Database.

The data in this layer are from a number of published and unpublished sets produced by the Bigelow Laboratory. The source projects were conducted primarily to examine contaminant (e.g. trace metals, PAHs) distributions, but also produced sediment textural data. The data were originally converted into digital format for inclusion in the Gulf of Maine Contaminated Sediments Database.

This data release includes grain-size measurements of sediment samples collected from the substrate surface and uppermost 10 cm of sediment deposits in the Klamath estuary, northern California. Samples were collected using a BMH-60 bed-material sampler deployed from a boat, or by hand trowel from subaerial or shallow-water (less than 0.5 m water depth) regions along the estuary margins and side channels. Sediment grain size was analyzed at the U.S. Geological Survey (USGS) laboratory in Santa Cruz, Calif. Particles coarser than 2 mm were sieved using a RO-TAP sieve shaker, and particles finer than 2 mm were analyzed with a Coulter laser particle-size analyzer (LPSA), after organic matter had been removed using a hydrogen peroxide solution. At some submerged locations where sampling was attempted, no sample was recovered. The field crew observed this occurring in places where the substrate was too coarse-grained to be collected by the bed-material sampler (cobbles), where large particles were embedded in finer (poorly sorted) matrix, and where sediment was covered by algal mats thick enough to prevent the sampler from accessing the sedimentary substrate. Locations where sampling was attempted but no sample was recovered are indicated in the ‘Comments’ column within the data spreadsheet. The sediment samples were collected under a Cultural Resources Management Permit issued by the Yurok Tribe, whose support the USGS acknowledges gratefully.

This data release includes grain-size measurements of sediment samples collected from the substrate surface and uppermost 10 cm of sediment deposits in the Klamath estuary, northern California. Samples were collected using a BMH-60 bed-material sampler deployed from a boat, or by hand trowel from subaerial or shallow-water (less than 0.5 m water depth) regions along the estuary margins and side channels. Sediment grain size was analyzed at the U.S. Geological Survey (USGS) laboratory in Santa Cruz, Calif. Particles coarser than 2 mm were sieved using a RO-TAP sieve shaker, and particles finer than 2 mm were analyzed with a Coulter laser particle-size analyzer (LPSA), after organic matter had been removed using a hydrogen peroxide solution. At some submerged locations where sampling was attempted, no sample was recovered. The field crew observed this occurring in places where the substrate was too coarse-grained to be collected by the bed-material sampler (cobbles), where large particles were embedded in finer (poorly sorted) matrix, and where sediment was covered by algal mats thick enough to prevent the sampler from accessing the sedimentary substrate. Locations where sampling was attempted but no sample was recovered are indicated in the Comments column within the data spreadsheet. The sediment samples were collected under a Cultural Resources Management Permit issued by the Yurok Tribe, whose support the USGS acknowledges gratefully.

This data release includes grain-size measurements of sediment samples collected from the substrate surface and uppermost 10 cm of sediment deposits in the Klamath estuary, northern California. Samples were collected using a BMH-60 bed-material sampler deployed from a boat, or by hand trowel from subaerial or shallow-water (less than 0.5 m water depth) regions along the estuary margins and side channels. Sediment grain size was analyzed at the U.S. Geological Survey (USGS) laboratory in Santa Cruz, Calif. Particles coarser than 2 mm were sieved using a RO-TAP sieve shaker, and particles finer than 2 mm were analyzed with a Coulter laser particle-size analyzer (LPSA), after organic matter had been removed using a hydrogen peroxide solution. At some submerged locations where sampling was attempted, no sample was recovered. The field crew observed this occurring in places where the substrate was too coarse-grained to be collected by the bed-material sampler (cobbles), where large particles were embedded in finer (poorly sorted) matrix, and where sediment was covered by algal mats thick enough to prevent the sampler from accessing the sedimentary substrate. Locations where sampling was attempted but no sample was recovered are indicated in the Comments column within the data spreadsheet. The sediment samples were collected under a Cultural Resources Management Permit issued by the Yurok Tribe, whose support the USGS acknowledges gratefully.