Brokaw
Steven Dutch, Natural and Applied Sciences, University
of Wisconsin - Green Bay
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NW 1/4 SW 1/4 Sec. 3 T29N R7E The Brokaw exit on Highway 51 exposes Proterozoic metaconglomerate and graywacke on both sides of the highway. This stretch of the Wisconsin River is in a pre-Pleistocene incised bedrock valley. This unit is probably what Laberge and Weis (1968) called the Marshall Hill Conglomerate. |
West Side of Highway 51
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Left: location of southbound on-ramp. |
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Left: metagraywacke |
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Left: metaconglomerate. |
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| Above: bedded metagraywacke | Below: metaconglomerate |
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East Side of Highway 51
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Left: location of northbound off-ramp. Below: general appearance of outcrops. Weathered joint surfaces reveal sedimentary features better than fresh surfaces. |
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Left and above: interbedded graywacke and metaconglomerate. Below: spectacular cross-bedding. |
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Left: Metaconglomerate lens between cross-bedded graywacke. |
Reference
Laberge, G. L. and Weis, L. W., 1968; A Greenstone Belt in Central Wisconsin? 32nd Annual Tri-State Geological Field Conference Guidebook. Stop 7, pp. 20-23.
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Created 4 May 2005, Last Update 17 Apr 2007
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