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Browse images from a wide range of science topics covered by USGS.
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.
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.
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.
USGS ecologist Kevin Lafferty visits the Exit Glacier in Alaska.
Geologists extract a hand-driven core from 2-3 m depth on Sitkinak Island, Alaska. The cores contain peat with interbedded sand layers that record inundation of the coast by prehistoric tsunamis. (l-r: Peter Haeussler, USGS; Andrew Kemp, Tufts University; Alan Nelson, USGS)
Geologists extract a hand-driven core from 2-3 m depth on Sitkinak Island, Alaska. The cores contain peat with interbedded sand layers that record inundation of the coast by prehistoric tsunamis. (l-r: Peter Haeussler, USGS; Andrew Kemp, Tufts University; Alan Nelson, USGS)
Geologists examine cores on Sitkinak Island, Alaska.
Geologists examine cores on Sitkinak Island, Alaska.
Base camp, Sitkinak Island.
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.
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.
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.
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.
Allen Bondurant measuring depth to permafrost along a thermokarst lake shore
Allen Bondurant measuring depth to permafrost along a thermokarst lake shore