Images

These “pom-pom” anemones (Liponema sp.) have attached to the rock in a place where there are probably very good currents, which bring small floating particles of food to them. Water depth is 1041 m (3415 ft).

A small juvenile skate (left) and a large rockfish (right) hang out on the murky, silty seafloor with sea stars. Water depth: 856 m (2808 ft).

Retrieving the MBARI (Monterey Bay Aquarium Research Institute) MiniROV from the Pacific Ocean offshore of California, on research vessel (R/V) Bold Horizon.

USGS scientist Pat Hart processing MCS data onboard the R/V Rachel Carson.

Mineral-laden water emerging from a hydrothermal vent on the Niua underwater volcano in the Lau Basin, southwest Pacific Ocean. As the water cools, minerals precipitate to form tower-like “chimneys.” Image taken during 2016 cruise “Virtual Vents.”  

Topography and bathymetry of southern Cascadia, which includes southern Oregon and northern California (seafloor depths between 200 and 3000 m are shown in the spectrum color scale from red (shallower) to purple (deeper). The land and continental shelf are shown in grayscale slope shading where darker colors represent steeper slopes.

Perspective views of multibeam bathymetry data acquired by the USGS aboard the R/V Medeia. Shallower depths in red. Arrows point to the distinct line in the seafloor associated with the Queen Charlotte-Fairweather fault.

Multichannel seismic-reflection profile across the Queen Charlotte-Fairweather fault, acquired aboard the R/V Norseman in August 2016. Dashed red line in enlarged section at lower right is the Queen Charlotte-Fairweather fault. m, meter; km, kilometer; ms, millisecond.

Graphic showing geophysical and sampling systems used to define the seafloor topography, surface sediments, and underlying geology.

Ice-like gas hydrates under capping rock encrusted with mussels on the sea floor of the northern Gulf of America.

Top of a ferromanganese crust sample collected from 1,896 meters water depth at Necker Ridge in the central north Pacific. The surface of this crust was in contact with ocean water and grew just 2 millimeters per million years.

Cross section of a seafloor crust (AKA, ferromanganese or cobalt-rich crusts) from the Marshall Islands collected at almost 2,000 meters depth. 

Multichannel seismic-reflection profile showing deformed and offset sediment layers below the outer continental shelf west of Sitka. The Sitka Sound fault is one of more than a dozen previously unmapped faults discovered in the July 2017 seismic-reflection data.

Multichannel seismic-reflection profile showing deformed sediment layers on the Pacific plate, just seaward of the Queen Charlotte-Fairweather fault near the south end of the study area. Location of profile shown by southern-most yellow line on trackline map, near Noyes Cyn. (Canyon).

Schematic showing how sediment on the seafloor moves in response to a force created by the combined action of tides, ocean waves, and wind-driven currents.

Phosphorite rock formed on the seafloor in Southern California.

A ship will tow this green cable, which contains underwater microphones that record sound reflected off layers beneath the seafloor. USGS scientists will use the data to pinpoint the location of faults.

Study region along the Queen Charlotte-Fairweather fault offshore southeastern Alaska. Rectangles show locations of the two USGS-led marine geophysical surveys in May and August 2015. The third cruise was offshore Haida Gwaii, British Columbia, and southern Alaska in September 2015.

Multichannel seismic-reflection profile showing sediment layers beneath the seafloor disrupted by the Queen Charlotte-Fairweather fault near Cross Sound. The profile is approximately 16 kilometers across, and it extends approximately 370 meters beneath the seafloor. See related multimedia below, for the location of this profile.

Seafloor trace of the Queen Charlotte-Fairweather fault (from top left to bottom right) offsets the edge of the Yakobi Sea Valley off southeast Alaska. This 700-mile-long fault has generated large earthquakes in the past. Future shocks—and tsunamis—could threaten coastal communities in the U.S. and Canada. (Color-coded depths, in meters, were mapped in 2015.)

Enlarged details of Survey Area 1 showing new multibeam bathymetry data (rainbow colors) acquired on R/V Solstice near Cross Sound and Glacier Bay National Park, southeastern Alaska. Arrows highlight the surface expression, or trace, of the Queen Charlotte-Fairweather fault.