Micrograph of Deformed Quartz Sandstone

Print

This micrograph colorfully illustrates deformed quartz grains in a well-cemented quartz sandstone from the Cambrian Antietam Formation, a prominent geologic unit in the Blue Ridge geologic province.  Many of the individual sand grains are elongated (~horizontal orientation), but not recrystallized.  Photo taken in cross polarized light with the gypsum plate inserted.

Fault Breccia in the Blue Ridge

Photomicrograph of fault breccia in the Antietam Formation, Blue Ridge province. Breccias form when rocks are extensively fractured in fault zones and are cemented together when minerals precipitate in the cracks and fractures. Note the angular fragments (fr) of quartz sandstone in a matrix of fine-grained iron oxide cement (ic). Field of View 4 x 2.7 mm, Cross Polarized Light.

Photomicrograph of fault breccia in the Cambrian Antietam Formation, Blue Ridge province. Breccias form when rocks are extensively fractured in fault zones and are cemented together when minerals precipitate in the cracks and fractures. Note the angular fragments (fr) of quartz sandstone in a matrix of fine-grained iron oxide cement (ic). Field of view 4 […]