Images

Big Pine Volcanic Field, California, from southwest cinder cone, with US Route 395 and Owens River in view

Pyroclastic flow (dense darker grey billowing mass) travels down slope of Mayon volcano, Philippines while ash column rises from the vent. Dilute, lighter-colored ash billows off leading edge.

Old Faithful geyser in eruption at Yellowstone National Park's Upper Geyser Basin.

GPS measurements provide models of the direction and rate (length of arrow) of deformation at the summit of Mauna Loa. Arrows pointing in multiple directions away from the summit indicate inflation.

Due to the cataclysmic eruption of May 18, 1980, many of the locations annotated on this map are now either covered or no longer visible.

Brimstone Basin, Yellowstone, aerial photo with overlay of two types of altered ground (light blue and pale pink shading) and locations of gas measurements (red dots). 2012 study

No date exists for this photograph, but the image is likely circa 1900. Note the postcard copyright date of 1903.

Quaternary volcanic rocks are shown in black, and main centers are labeled. Chilliwack batholith and Pemberton belt represent Oligocene– Miocene arc 20–50 km inboard of Quaternary Garibaldi arc. Dashed line surrounding Puget Lowland shows maximum extent of Puget lobe of Cordilleran Ice Sheet during the last glaciation.

Geothermal ice cave at Mount Baker's summit formed by melting of a glacier due to increased heat from subsurface magma and fumarole on the surface expelling hot gasses.

Geologic Hazards at Volcanoes (click for larger version)

Adam Mosbrucker tests equipment (Acoustic Doppler Current Profiler, survey-grade RTK-GPS and a map-grade GPS) in preparation for a lake bottom survey.

Visible relief in the hillside exposure is about 800-900 ft. Dusty assemblage deposit occurred approximately between 5100 and 5500 yr B.P. Magma volume of >5 km3, which is a lot for what was probably one eruptive stage. The source lava dome is gone, apparently having disintegrated entirely during extrusion and subsequent glacial interaction.

Non-volcanic peaks of the North Cascades lie in the background. Dusty Creek drainage experiences regular lahars. Gamma Ridge Formation are hydrothermally altered rocks on left ridge. Loose pyroclastic fill deposits cap right ridge; Eastern view, Glacier Peak, Washington.

Exposed rock ridges are thick Pleistocene lava flows that were confined between large glaciers. Glacier Peak, Washington, view north.

Boulder Creek leading from Mount Baker, Washington is a hydrology monitoring site where water is collected and measured for chemicals that may signal volcanic unrest.

Lahar deposit cross section in the Trout Lake lowland, which originated from Mount Adams. Thickness of deposit is about 2.5 m (8 ft).

Mount Bachelor seen from South Sister across Sparks Lake. One of the "Devils Chain" domes visible in lower image foreground. Oregon

Mount Bachelor viewed from the south. Sparks Lake and South Sister visible in the background. Oregon.

Mount Scott Lookout seismic and GPS volcano monitoring station, view from the southwest. Near Crater Lake, Oregon.

Deformation monitoring equipment—GPS antenna maintenance on south side of Crater Lake National Park Boathouse on Wizard Island. Oregon

Mount Bachelor's east facing ski slopes at sunrise.