Images

Repeat oblique photographs of Gulkana glaciers in Alaska.  1967, Unknown USGS photographer. 2016, L. Sass, USGS.

Repeat oblique photographs of Wolverine glacier in Alaska.  1966 image by unknown USGS photographer; 2015 image by L. Sass, USGS.

Photograph taken in 1964 of the main part of the Chenega village site in Alaska. Pilings in the ground mark the former locations of homes swept away by tsunami waves. The schoolhouse on high ground was undamaged.

This, the first of two repeat photographs, documents significant changes that have occurred during the nine years between photographs A and B. Although Muir Glacier has retreated more than 3 kilometers and thinned more than 100 meters, exposing Muir Inlet, it remains connected with tributary Riggs Glacier. White Thunder Ridge remains devoid of vegetation.

This northeast-looking photograph, on the southeastern side of White Thunder Ridge ,shows the lower reaches of Muir Glacier, then a large tidewater calving valley glacier, and its tributary Riggs Glacier. The séracs in the lower right-hand corner of the photograph mark Muir Glacier’s terminus. The ice thickness is more than 700 meters.

Volcanic ash drifts around houses at Katmai after the June 1912 eruption of Novarupta Volcano. Church in the distant background. August 13, 1912.

A tidal marsh bank exposed during low tide on Sitkinak Island, Alaska. The bank reveals ledges of alternating peat and silt. Abrupt uplift and subsidence during large megathrust earthquakes is interpreted to be the cause of the alternating layers.

Base camp, Sitkinak Island.

Geologists examine cores on Sitkinak Island, Alaska.

Geologists examine an exposure of a tidal marsh bank on Sitkinak Island, Alaska. The bank exposes interbedded peat and silt that records sudden vertical land movements associated with megathrust fault slip during large earthquakes.

Allen Bondurant measuring depth to permafrost along a thermokarst lake shore

Ed Pfeifer of the USGS Southwest Geographic Science Team collecting water samples during field work for a study of Dall sheep habitat in Denali National Park, Alaska.

Ed Pfeifer of the USGS Southwest Geographic Science Team recording field notes in alpine tundra during a field study of Dall sheep habitat in Denali National Park, Alaska, on July 29, 2009

Fireweed gains a foothold in a burn area of the White Mountains in Alaska.

Coastal Marsh along Cook Inlet across from Anchorage Alaska.

Geologists driving a core into marsh sediment to document interbedded peat and silt that records sudden vertical land movements associated with megathrust fault slip during large earthquakes.

An Alaska Volcano Observatory Monitoring station with Peulik Volcano behind. This is the main repeater for the Peulik monitoring network located on Whale Mountain, Beecharaof National Wildlife Refuge.

Northslope of Alaska in May

Exposures of sedimentary rocks in the western Brooks Range, Alaska were evaluated for their contents of metals and phosphate and for their petroleum maturation histories to determine the potential for undiscovered resources in the southern National Petroleum Reserve Alaska.

Eagle was our put-in point for our first synoptic cruise down the Yukon River.

USGS ecologist Kevin Lafferty visits the Exit Glacier in Alaska.