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Impact-Shocked Quartz Grain

Red ball iconMANSON IMPACT STRUCTURE

Impact Shocked Quartz Grain  

PHOTOMICROGRAPH

Crystalline Basement Rocks

Impact-Shocked Quartz Grain

2-A Core--646 feet


Fine, dark lines are planar deformation features (multiple intersecting sets of these features as seen here are considered definitive evidence of impact origin). Broader, irregular dark lines are conjugate fracture sets. The brown mottling is "toasting," common to shocked quartz at Manson.

--field 3.2 x 2.1 mm
--plane-polarized light

 
   
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