Browse Items (1125 total)

Western Minerals GC OCR.pdf
OCR PDF of supplemental information for the Grand Canyon collection.

http://dl.dropbox.com/u/66399955/GC-1.JPG
Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-1A.JPG
Both cross polarized and plain polarized images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-2.JPG
Part of the The Granite Gorge Metamorphic Suite, this is usually considered a metavolcanic, and its mineralogy is dominated by quartz and mica.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-3.JPG
This sample is mis-labeled as a pegmatite. It is really a porphyritic dike material that cuts through the Zoroaster Granite. The phenocrysts are hornblende.

http://dl.dropbox.com/u/66399955/GC-4.JPG
Sandstone shows metamorphic overprinting with triple junctions between quartz grains common.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-5.JPG
Mottled lithology of the Muav Limestone.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-6.JPG
Green clay lithology of the Bright Angel Shale.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-7.JPG
Red siltstone lithology of the Bright Angel Shale.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-8.JPG
Limestone containing fossils of the alga, Girvanella.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-9.JPG
A silty-shale where the clasts are dominated by quartz. Sample collected from an area typified by interbedded limestones and shale.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-10.JPG
Oblitic and Crinoidal Lithology.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-11.JPG
Fine-grained limestone with occasional fossil remains.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-12.JPG
Collected from the Redwall Formation, this is a highly silicious sample defined in the suite's documentation as chert, but the sample lacks the nano-crystalline appearance of a traditional chert. It appears to be more of a slightly metamorphosed…

http://dl.dropbox.com/u/66399955/GC-13.JPG
Though listed as a limestone, this sample is best described as a conglomerate with calcite present in the matrix. This sample was collected from a bed of conglomerate lithology just below contact with Supai formation.

Both thin section images…

http://dl.dropbox.com/u/66399955/GC-14.JPG
A classic red-bed sample typical of the sandstones from the Supai Formation.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-15.JPG
Classic red-bed sample from the Supai Formation with silt-sized grains of mostly quartz. Some grains are semi-rounded.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-16.JPG
A ferruginous sample.

Both thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-17.JPG
A buff-colored siltstone/sandstone. The grains are angular and are quartz-dominated.

Thin section images were taken at a 400x magnification.

http://dl.dropbox.com/u/66399955/GC-18.JPG
A sample from the gamma member of the Toroweap Formation. It is an orangish-brown sample.
Both thin section images were taken at a 400x magnification.