Missouri State University

Silvermines

The Silvermines Recreation Area in the Mark Twain National Forest exposes the Silvermines Granite, one of the "ring plutons" that formed as felsic magma rose along fractures around the perimeter of the Butler Hill Caldera.  Late-stage mafic dikes cross-cut the Silvermine Granite.  One of these dikes, the infamous "Silvermines Quartz Basalt", contains abundant large xenocrysts of quartz and alkali feldspar, interpreted to have come from the underlying Butler Hill Granite.

 

Photo of geology students at Silver Mines, southeastern MissouriPhoto of geology students at Silver Mines, southeastern Missouri 

Photo of geology student at Silver Mines, southeastern MissouriPhoto of Dr. Moeglin with geology students at Silver Mines, southeastern Missouri