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Crystalline-Clast Breccia with Sandy Matrix

Red ball iconMANSON IMPACT STRUCTURE

Core

CORE PHOTOGRAPH

Crystalline-Clast Breccia
with Sandy Matrix

M-1 core, 287 feet

 

Salmon colored grain is feldspar from pegmatite, light clasts are gneiss, dark gray clasts are hornblende gneiss. The matrix is finely brecciated crystalline rock clasts and mineral grains from disaggregated crystalline rock (photomicrograph). This unit may represent the impact -brecciated floor of the transient crater, and was lifted up with the central peak core is NX (1 7/8" diameter)  
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