Images

USGS scientist David Ponce measuring gravity using a gravimeter along the Hayward-Rodgers Creek fault zone just north of San Pablo Bay, California.

USGS oceanographer Kurt Rosenberger prepares a mooring for deployment from the research vessel Rachel Carson on October 6, 2015. The tan, cone-shaped instrument is a sediment trap. Near the far end of the trap is a CTD (with small red tag) for measuring seawater conductivity (related to salinity), temperature, and depth.

Scientists deploy a mooring holding current meters and other instruments on October 6, 2015.

A large wave crashes on the reef at Laysan Island, located in the Northwestern Hawaiian Islands.

This flooded airport runway used to be the main lifeline for inhabitants of Barter Island, Alaska, before it was relocated in response to consistent flooding.

U.S. Geological Survey scientist walks on a coastal bluff in Alaska.

Left, Cordell Johnson drilling and coring the interior of the bluff to ground-truth geophysical methods. Right, a core section filled mostly with ice.

Photograph of an eroding coastal bluff on Barter Island on the northern coast of Alaska.

San Clemente Dam was a 106-foot-high concrete arch dam that was located approximately 18.5 miles from the Pacific Ocean on the Carmel River. It was built in 1921 to create a reservoir to support the growing residential, agricultural, and tourism-related development.

Sam Johnson explaining details of the Hosgri fault zone at USGS offices in Santa Cruz.

Geophysicist Sam Johnson explaining details of the San Andreas fault zone at USGS offices in Santa Cruz.

Alaska Department of Fish and Games vessel Solstice carried USGS scientists for three weeks in May 2015 while they mapped 650 square kilometers of seafloor and features beneath the seafloor in fine detail.

 This colored shaded-relief bathymetry map of the Offshore of San Francisco map area in northern California was generated from bathymetry data collected by California State University, Monterey Bay (CSUMB) and by Fugro Pelagos (fig. 1).

Mapping along the Queen Charlotte-Fairweather fault required several days aboard the Alaska Department of Fish and Game research vessel Solstice. Here, the boat sits in a marina near Cordova, Alaska.

Aerial photograph of Kwajalein Atoll showing its low-lying islands and coral reefs.

Aerial photograph of Kwajalein Atoll showing its low-lying islands and coral reefs.

Aerial photograph of Kwajalein Atoll showing its low-lying islands and coral reefs.

Aerial photograph of Kwajalein Atoll showing its low-lying islands and coral reefs.

Aerial photograph of Kwajalein Atoll showing its low-lying islands and coral reefs.

Underwater image of a wave breaking over a coral reef on Kwajalein Atoll in the Republic of the Marshall Islands. This image shows how the high hydrodynamic roughness of live, healthy corals causes friction that induces breaking of waves over coral reefs, reducing wave energy at the shoreline that can cause flooding and island overwash.

Aerial photograph of Kwajalein Atoll showing its low-lying islands and coral reefs.