Oconto County contains very diverse bedrock. The southeastern portion consists of a section of Cambrian and Ordovician sedimentary rocks dipping monoclinally gently to the east, off the Wisconsin arch. The Cambrian rocks are mostly clastic sandstones, which the Ordovician rocks carbonate dominated. The northwestern portion contains diverse Proterozoic metamorphic and igneous rocks. Some are granites, meta-volcanic and meta-sedimentary rocks deformed during the 1.80 – 1.85 billion year old Penokean Orogeny. The Penokean orogeny was a continent-continent collision, with the rocks seen in the county being ocean crust and island arc materials caught up in the collision. Excellent examples can be seen in outcrop in the Mountain area. Quartzite outcrops at McCaslin Mountain, and can yield nice quartz crystals. Much of the Precambrian in the County is part of the anorogenic 1.4 billion year old Wolf river Batholith. Thick glacial drift, lakes and forests make outcrops scarce, but these deposits can yield interesting glacially transported rocks and minerals.
Mineral ListMineral list contains entries from the region specified including sub-localities
28 entries listed. 19 valid minerals.
Localities in this Region
The above list contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.
This page is currently not sponsored. To sponsor this page click here.
|Fade toolbar when not in focus||Fix toolbar to bottom of page|
|Hide Social Media Links|
|Slideshow frame delay||seconds|