A site dedicated to the geology and the geomorphology of the United States
States: ID
MN
MT NC
NY SC WY
Rocks and Minerals
Adirondack Mountains, New York
Lowlands, Carthage-Colton shear zone, Highlands, massif anorthosite.
![](home/2420-popple-hill-gneiss-200px.jpg)
Lombard Thrust, Montana
Lombard thrust (Helena salient), Toston fault, Townsend fault zone, Hossfeldt anticline, kink folds.
![](home/1437-lombard-thrust-missouri-river-canyon-200px.jpg)
![](home/hossfeldt-anticl-eustis-cross-section-200px.jpg)
Rock Springs Uplift and Green River Basin, Wyoming
Rock Springs uplift, Green River basin, Leucite Hills, Killpecker Sand Dunes.
![](home/rock-springs-uplift-geol-map-H150px.jpg)
![Rock Springs uplift, Wyoming thumbnail](./home/rock-springs-uplift-200px.jpg)
Wind River Canyon, Wyoming
Archean and Paleozoic rocks are exposed in the spectacular Wind River canyon.
![Wind River canyon, Wyoming thumbnail](home/2063-43-32-29-N-200px.jpg)
![Wind River canyon, Wyoming thumbnail](home/2096-43-27-30-N-200px.jpg)
The Archean Terranes of Minnesota
![morton gneiss](home/morton-gneiss-11-200px.jpg)
![](home/minnesota-archean-terranes-v2-8-200px.jpg)
Click on image for full-size display
Morton Gneiss, in the Minnesota River Valley, is an Archean rock (ca. 3.5Ga old):
light-gray tonalite and dark-gray amphibolite inclusions. Quarter gives size.
North Carolina Geologic Maps
Full-resolution Geologic map of North Carolina (NC Geological Survey, 1985)
![NC geologic map thumbnail](home/NC-geologic-map-NCGS-1985-200px.jpg)
Tectonic maps of the North Carolina Inner Piedmont
![NC geologic map thumbnail](home/NC-inner-piedmont-on-geologic-map-200px.jpg)
![NC geologic map thumbnail](home/NC-inner-piedmont-on-topo-map-200px.jpg)
![NC geologic map thumbnail](home/NC-inner-piedmont-on-NED-map-200px.jpg)
Geology of the Bruneau Canyon, Idaho
Description, maps, photos, origin of one of the most scenic canyons of North America
![Bruneau basin map, Idaho-thumbnail](./home/bruneau-canyon-idaho-N-map-200px.jpg)
![Bruneau Canyon, Idaho-thumbnail](home/bruneau-canyon-idaho-200px.jpg)
Clarendon County, South Carolina
Case study of a county of the Middle and Lower Atlantic Coastal Plain : geomorphology, soils, vegetation, agriculture
Currently available: physiographic maps, soil map.
![Geomophology of Clarendon County, SC-thumbnail](home/clarendon-co-geomorphologic-map-200px.jpg)
![Clarendon County, SC soil map-thumbnail](home/clarendon-co-sc-soil-map-200px.jpg)
Microphotographs of Rocks and Minerals:
Biotite
![](home/biotite-unit-cell-200px.jpg)
![biotite crystals-close-up-thumbnail](home/biotite-crystals-200px.jpg)
![](home/morton-gneiss-thin-section-01-XPL-200px.jpg)
Hornblende
![](home/hornblende-hand-sample-closeup-200px.jpg)
![](home/hornblende-in-andesite-thin-section-ppl-200px.jpg)
Anorthosite:
Plagioclase (albite twinning, Carlsbad twinning, pericline twinning, Michel Lévy method), hematite, quartz (undulose extinction), sericite
![](home/2488a-anorthosite-plagioclase-hematite-200px.jpg)
![](home/labradorite-S9647-3-100x-XPL-264deg-200px.jpg)