Skip past header information
USGS - science for a changing world
NOAA Logo with link to NOAA Home Page.  

U.S. Geological Survey Open-File Report 2011–1005

Surficial Geology of the Sea Floor in Central Rhode Island Sound Southeast of Point Judith, Rhode Island


Bottom Photography

Skip past contents information
Click on figures for larger images
Thumbnail image of figure 18 and link to larger figure. Map showing photograph locations in the study area.
Figure 18. Location of bottom photographs taken during U.S. Geological Survey cruise 2010-033-FA.
Thumbnail image of figure 19 and link to larger figure. Photograph of a sandy sea floor.
Figure 19. Photograph of a typical sandy sea floor at station 996-7, located in the north-central part of the study area, showing burrows, scattered shells, and animal tracks.
Thumbnail image of figure 20 and link to larger figure. Photograph of gravel in the study area.
Figure 20. Photograph of gravel at station 996-11, located in the central part of the study area.

Sea-floor photography was collected at 25 stations within the H11996 survey area as part of this study (fig. 18). The small SEABOSS system was used to obtain video photography and 1 to 7 still photographs as the RV Rafael drifted over the seabed for 2 to 5 minutes at each station. A total of 116 still photographs of the sea floor were taken. The field of view of each image is approximately 50 cm (SEABOSS 50 cm above the bottom).

Photographs in the study area show that sandy areas are typically burrowed with scattered shells, amphipod communities, and worm tubes (fig. 19). Coarse gravel (boulders and cobbles) is commonly overgrown with hydrozoans and anemones, suggesting that they are immobile (fig. 20).

Scour depressions are floored with rippled sand and some gravel (stations 996-18, 996-19, 996-21, 996-22, and 996-24) and are surrounded by a flat to undulating sandy sea floor with some faint ripples and scattered patches of gravel (stations 996-6, 996-10, 996-13, 996-17, and 996-20). Photography from stations 996-9 and 996-15 transects the scour depressions and the surrounding sea floor. Similar features were previously described as tabular erosional outliers in an area about 14 km to the northeast (McMullen and others, 2007) and are also seen in eastern Rhode Island Sound west of Gay Head, Mass. (Poppe and others, 2011). Scour depressions are thought to be preferentially eroded by bottom currents as their coarser grained floors enhance turbulence in the water (Murray and Thieler, 2004). We interpret these features to form, and be maintained, by scour from bottom currents during storm events.

Low-resolution images (150 x 112 pixels) of the photographs may be viewed by browsing the thumbnails in the photo gallery below. These thumbnails are hyperlinked to medium-resolution images (600 x 450 pixels) for more detailed viewing. A WinZip file with all the medium-resolution images from the study area may be accessed by clicking here. Alternatively, the directory containing the full-resolution images may be accessed by clicking here. These full-resolution images (2560 x 1920 pixels) can be identified using the .jpg image names in the galleries below. Textural analyses of samples obtained at these stations, where available, are provided in the Sediments section of this report. Individuals interested in obtaining the video photography collected in this area may do so at the Data Library of the USGS Woods Hole Coastal and Marine Science Center, Woods Hole, Mass.

Station  /  Lithologic Description

996-1 / Pea- to cobble-sized gravel with a few scattered boulders. Larger cobbles and boulders are overgrown with hydrozoans and a few anemone. A thin veneer of fine-grained siliciclastic or organic debris covers the rocks. Scattered shells are present; shrimp and red starfish were observed.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_1a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_1b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_1c
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_1d

 

996-2 / Scattered boulders overgrown primarily with hydrozoans surrounded by pea- to cobble-sized gravel and patches of current-rippled sand. A thin veneer of fine-grained siliciclastic or organic debris covers the rocks. Finfish, scallops, rust-colored algae, and cancer crabs are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_2a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_2b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_2c

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_2d

996-3 / Flat to faintly rippled, commonly patchy gravelly sand with pea- to pebble-sized gravel. Hydrozoans grow on scattered cobbles. Patches of sand have spotty communities of amphipods, animal tracks, and a few scattered shells. Cancer crabs and finfish are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_3a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_3b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_3c
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_3d

 

996-4 / Undulating to faintly rippled sand with a few patches of amphipod tubes and pea gravel. Burrows, animal tracks, starfish, skate egg casings, and a trace of shell debris are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_4a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_4b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_4c
 
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_4d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_4e

 

   

996-5 / Flat sandy sea floor with scattered patches of pea- to pebble-sized gravel. Hydrozoans grow on a few scattered cobbles. Amphipod communities and small burrows have a patchy distribution. Starfish, hermit crabs, animal tracks, and scattered shells were observed on the sea floor; jellyfish were observed in the water.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_5a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_5b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_5c

 
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_5d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_5e

 


 

996-6 / Flat to faintly rippled, commonly patchy gravelly sand with pea- to pebble-sized gravel. Cancer crabs, starfish, scallops, and scattered shells are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_6a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_6b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_6c

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_6d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_6e
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_6f

 


 

996-7 / Flat to undulating sand with numerous small burrows and scattered shells and amphipod communities. Starfish, shrimp, a few mussels, and animal tracks are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_7a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_7b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_7c

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_7d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_7e

 


 

996-8 / Flat to undulating sea floor composed of muddy sand with scattered small and large burrows and numerous animal tracks. Starfish, cancer crabs, and a trace of shell debris are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_8a

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_8b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_8c
 
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_8d

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_8e

 

 

996-9 / Undulating to faintly rippled sand with small burrows, amphipod and worm tubes, and a trace of shell hash. Starfish, animal tracks, and sand dollars were observed.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_9a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_9b

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_9c

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_9d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_9e
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_9f

 


 

996-10 / Undulating to faintly rippled sand with scattered small burrows, and amphipod and worm tubes. Red and white starfish, cancer crabs, and hermit crabs were observed.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_10a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_10b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_10c


Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_10d

996-11 / Scattered boulders separated by pea- to cobble-sized gravel. Larger cobbles and boulders are overgrown with hydrozoans, algae, and a few anemones. A thin veneer of fine-grained siliciclastic or organic debris covers the rocks. Scattered shells are present; finfish, soft coral, cancer crabs, and red starfish were observed.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_11a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_11b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_11c

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_11d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_11e

 


 

996-12 / Flat to undulating sea floor composed of fine-grained sand with scattered small burrows and numerous animal tracks. Starfish, hermit crabs, cancer crabs, shrimp, small patches of amphipod tubes, and a trace of shell debris are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_12a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_12b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_12c


Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_12d

996-13 / Flat to undulating sea floor composed of fine-grained sand with scattered shell debris and numerous animal tracks. Starfish, cancer crabs, small burrows, moon snail casings, skate egg casing, and some worm and amphipod tubes are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_13a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_13b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_13c

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_13d

 

996-14 / Flat to undulating sea floor composed of muddy sand with scattered small and large burrows and numerous animal tracks. Lobster and crab burrows, amphipod tubes, and a few shells are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_14a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_14b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_14c


 

996-15 / Flat to undulating sea floor composed of fine-grained sand with scattered shells and shell debris. Starfish, skate, scallops, small burrows, animal tracks, moon snail casings, and some worm and amphipod tubes are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_15a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_15b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_15c


Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_15d

996-16 / Flat to undulating to faintly rippled sea floor composed of sand with scattered shells and shell debris. Starfish and worm and amphipod tubes are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_16a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_16b

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_16c


 

996-17 / Flat to faintly rippled gravelly sand with patches of pea- to cobble-sized gravel. Hydrozoans grow on the larger gravel. A thin veneer of fine-grained siliciclastic or organic debris covers the rocks. Patches of sand have worm tubes, animal tracks, and small patches of amphipods tubes. Lobster, scallops, and scattered shells and shell debris are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_17a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_17b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_17c

 
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_17d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_17e

 


 

996-18 / Pea- to pebble-sized gravel interspaced with patches of sand. A thin veneer of fine-grained siliciclastic or organic debris commonly covers the gravel. Starfish, animal tracks, and finfish are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_18a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_18b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_18c

 
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_18d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_18e

 


 

996-19 / Rippled or megarippled sand with shell debris concentrated in the troughs of the bedforms. Starfish, hermit crabs, and scallop shells are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_19a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_19b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_19c

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_19d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_19e
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_19f

 


 

996-20 / Flat to undulating sea floor composed of sand with scattered burrows, shells, and shell debris. Small patches of amphipod tubes are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_20a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_20b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_20c


 

 

996-21 / Rippled sand and gravelly sand with shell debris concentrated in the troughs of the bedforms and small patches of pea to pebble-sized gravel. Starfish, cancer crabs, burrows, and worm tubes are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_21a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_21b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_21c

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_21d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_21e
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_21f

 


 

 

996-22 / Flat to undulating to faintly rippled sea floor composed of sand with scattered shells and shell debris. Starfish, flounder, cancer crabs, hermit crabs, burrows, and worm and amphipod tubes are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_22a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_22b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_22c

 

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_22d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_22e

 


 

 

996-23 / Undulating to faintly rippled sand with scattered small burrows and amphipod and worm tubes. A thin veneer of fine-grained siliciclastic or organic debris covers the sand and is easily disturbed by the sampler. Starfish, animal tracks, and cancer crabs were observed.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_23a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_23b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_23c

 

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_23d

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_23e

 

 

996-24 / Rippled or megarippled sand with shell debris concentrated in the troughs of the bedforms. Starfish, scallops, burrows, and worm and amphipod tubes are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_24a
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_24b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_24c

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_24d
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_24e
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_24f

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_24g

 

996-25 / Rippled or megarippled sand with shell debris concentrated in the troughs of the bedforms. Starfish and worm and amphipod tubes are present.

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_25a

 

Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_25b
Thumbnail of a photograph of the sea floor, click to view full scale photograh.
996_25c

 

 

Skip USGS links group

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USAGov logo U.S. Department of the Interior | U.S. Geological Survey
End of USGS links group