Steven Dutch, Professor Emeritus, Natural and Applied Sciences, University of Wisconsin - Green Bay
NW 1/4 Sec 34, T23 N, R 6 E
Large outcrops of Archean granitic and tonalitic gneiss downriver from the dam just north of Biron. Access is from public parking at the north end of the dam. |
|
View of the dam | |
The main outcrop area | |
Left and below: Looking east from the outcrop area to the dam.
Below: looking along the contact between light granitic gneiss and darker tonalitic gneiss. |
|
Close-up of foliated granitic gneiss | |
Close-up of foliated tonalite | |
Contact between granitic and tonalitic gneiss | |
Contact between granitic and tonalitic gneiss | |
Two ages of dikes in tonalite gneiss. | |
Banded tonalitic gneiss | |
Mafic dike cutting through granitic gneiss. | |
Differential weathering of granitic gneiss and tonalitic gneiss (darker and more weathered). | |
Differential weathering of granitic gneiss and tonalitic gneiss (darker and more weathered). | |
Chemical weathering along joint plane in tonalitic gneiss |
Return to Geology of Wisconsin Index
Return to Geologic Localities Index
Return to Professor Dutch's Home Page
Created 3 May 2005, Last Update 15 Jan 2020