Geologic map of the Talkeetna Mountains C-4 Quadrangle and adjoining areas, central Alaska

The Alaska Division of Geological & Geophysical Surveys (DGGS), in partnership with the U.S. National Cooperative Geologic Mapping Program, mapped approximately 450 mi2 of the Talkeetna Mountains region of central Alaska at 1:50,000 scale over the course of six weeks in 2014. This area contains significant exposures of Late Triassic mafic volcanics and gabbro sills that have been the focus of region-wide exploration for the Strategic and Critical platinum-group elements (PGEs). The area also exposes numerous inactive and possibly active faults which project through the area of proposed hydropower development. The resulting geologic map offers an improved understanding of the geology, structural history, and mineral...

Tags: 40Ar/39Ar, Aerial Geology, Aerial Photography, Alluvial, Alluvial Deposits, All tags... Amphibolite Facies Units, Bedrock Geologic Map, Bedrock Geology, Brachiopods, Cleary Creek, Colluvial Deposits, Cordilleran Ice Sheet, Crinoids, Esker, Faulting, Faults, Floodplain, Fluvial, Fossils, Geochronology, Geologic Map, Geologic Materials, Geomorphology, Glacial, Glacial Deposits, Glacial Drift, Glacial Geology, Glacial Geomorphology, Glacial History, Glacial Lake, Glacial Processes, Glacial Stratigraphy, Glaciation, Ice Contact Deposits, Ice-Contact, Iron Creek, Lacustrine, Lacustrine Sedimentation, Landslide, Landslide Deposit, Outwash, Outwash Fan, Paleochannel, Permafrost and Periglacial, Remote Sensing, Rock Glaciers, Rock-Glacier Deposits, Rockfall, STATEMAP Project, Sand and Gravel, Slides, Slope Instability, Soil Creep, Stephan Lake, Surficial, Surficial Geologic Map, Surficial Geology, Talkeetna Mountains, Talkeetna Mountains Quadrangle, Talkeetna River, Till, geoscientificInformation, Fewer tags

Extent of Pliocene hyaloclastic deposits and related lava flows in the Columbia Gorge, Oregon and Washington

This dataset contains polygons representing deposits of hyaloclastic debris that were generated between about 3.5 and 3.0 million years ago when a series of basaltic lava flows entered the canyon of the ancestral Columbia River. The lava flows were erupted from volcanoes in the area of the Hood River graben of McClaughry and others (2012), generally have low-potassium tholeiitic basalt composition, and were part of a widespread pulse of mafic volcanism in the northern Oregon Cascade Range that occurred between about 4.4 and 2.1 million years ago (Conrey and others, 1996). Lava flows that entered the ancestral Columbia River were rapidly chilled and fragmented during interaction with water (Trimble, 1963, Swanson,...

Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Clark County, Columbia Gorge, Columbia River, Columbia River Gorge National Scenic Area, Hood River, All tags... Hood River County, Multnomah, Multnomah County, Oregon, Oregon, Pacific Northwest, Stratigraphy, USGS Science Data Catalog (SDC), Volcanology, Washington, Washington, geologic maps, geology, geoscientificInformation, hyaloclastite, palagonite, paleochannel, sedimentary rocks, sideromelane, tholeiitic basalt, volcanic rocks, Fewer tags