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Crystalline-Clast Breccia with Melt Matrix Sanidine Grain

Red ball iconMANSON IMPACT STRUCTURE

Sanidine Grain  

PHOTOMICROGRAPH

Crystalline-Clast Breccia
with Melt Matrix

Sanidine Grain

M-1 Core--331 feet

Dark matrix is melt-rock; mottled grain (right) is shocked, partially melted and recrystallized quartz; sanidine grain recrystallized from melted feldspar in the impact melt; similar grains yielded a 74 Ma age for the Manson impact.

field 3.2 x 2.1 mm
cross-polarized light

     
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