Images

On remote Barter Island, Alaska, Bruce Richmond (right) and Cordell Johnson drill into 500-foot-thick permafrost using a handheld drill with a 2-inch drill bit—a challenging task! It can take 3 hours to drill nearly 20 feet down.

Santa Barbara Channel region, showing locations of six California Seafloor Mapping Program (CSMP) map sets (red rectangles) and the outer boundary of California’s State Waters (yellow line).

Enlarged map of the Yakobi Sea Valley. Closeup view (upper right) shows right-lateral offset of the Yakobi Sea Valley wall by the Queen Charlotte-Fairweather fault. MCS, multichannel seismic; km, kilometers. For location, see the southeastern Alaska trackline map.

Gray-scale perspective view of Rincon Point, the subaerial part of a delta formed by boulders deposited at the mouth of Rincon Creek. A relict submerged boulder delta, formed by similar processes during lower stands of sea level, extends 1,500 meters offshore. Relief on this submerged delta causes wave refraction and a world-class surfbreak (inset image).

USGS Ocean Engineer Gerry Hatcher (left) monitors the view of the seafloor from the camera mounted on the Mini Muc and communicates with the ship’s bridge while USGS engineering technician Pete Dal Ferro uses a remote winch control to position the Mini Muc and trigger coring.

A personal watercraft ready to survey the surf zone, with custom waterproof displays linked to an echo sounder and a precision GPS receiver. These surveys require special training and permits.

Healthy Elkhorn coral (Acropora palmata) near unpopulated Buck Island, U.S. Virgin Islands. Elkhorn coral is one of many important reef-building species that create 3D structure on the seafloor. Coral reef structure provides habitat for marine life and helps break up waves as they approach the coastline.

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.

Enlarged from previous figure, this map shows a string of basins along the fault and offset of the south wall of the Yakobi Sea Valley. Line A–B marks the location of multichannel seismic-reflection profile.

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.

The relatively new camera stations at Santa Cruz and Madeira Beach have not yet imaged many rip channels, so this is an example from the U.S. Army Corps of Engineers Field Research Facility in Duck, North Carolina. In this time-averaged image from video taken September 1, 2015, the dark horizontal bands perpendicular to the beach indicate rip channels.

Flood maps from Our Coast, Our Future showing Stinson Beach today (slide 1); with a 50-centimeter sea-level rise (slide 2); and when an annual storm strikes in addition to 50-centimeter sea-level rise (slide 3). Green patches are low-lying areas prone to flooding.

Science crew aboard R/V Marcus G. Langseth. Ray Sliter (Pacific Coastal and Marine Science Center) and Deb Hutchison (Woods Hole Coastal and Marine Science Center) shown at far left.

Engineering technician Tim Elfers of the USGS Pacific Coastal and Marine Science Center navigates a personal watercraft (PWC) through waves offshore of central California. The PWC is equipped with sonar and GPS in order to map the nearshore seafloor.

These clams (Calyptogena spp.) were discovered in about 1000 meter-deep waters off the southern tip of Alaska near a 250-meter-high cone rising from the seafloor and 10 kilometers from the Queen Charlotte-Fairweather fault.

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.)

Cliff erosion is a common storm-induced hazard along the West Coast. Two condemned apartment buildings along Esplanade Avenue in Pacifica, California are shown here before their demolition in 2016 and 2017.

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.

Profile of newly discovered volcano-like cone in sonar record collected off southern Alaska. The cone’s summit is at about 1,000 meters water depth. Note fluid plume (blue) rising more than 700 meters upward from the summit.

A vibracore taken from a marshy area in Anahola Valley, Kaua‛i reveals a sandier mud layer.

The challenging and complex study environment of Molokaʻi’s (Hawaiʻi) fringing reef. Learn more about USGS studies on this island: “Coral Reef Project: Molokaʻi”