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CORE PHOTOGRAPH Crystalline Basement Rocks

Red ball iconMANSON IMPACT STRUCTURE

Core  

CORE PHOTOGRAPH

Crystalline Basement Rocks

2-A core, 357 feet

Augen gneiss with granite migmatite. This rock was lifted up about 5 km from its pre-impact position and is now near the center of the central peak. The macroscopic appearance of this rock was not changed by the impact, however, microscopically nearly every quartz grain shows planar deformation features and other evidence of impact (photomicrograph). The auge are cored by chromite grains that have been impact-fractured.

core is NX (1 7/8" diameter)

     
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