Mafic intrusions including pyroxenite, peridotite, gabbro, and lamprophyre

Mafic intrusions including pyroxenite, peridotite, gabbro, and lamprophyre. Defined largely by magnetic signature. One intrusion in Morrison County is ~1,791 Ma, and lithologically similar intrusions cut the Foley Granite (~1,774 Ma).
State Minnesota
Name Mafic intrusions including pyroxenite, peridotite, gabbro, and lamprophyre
Geologic age Paleoproterozoic
Lithologic constituents
Comments Part of the Geon 17 post-tectonic (post-Penokean orogeny) intrusions related to the Yavapai orogeny.
References

Jirsa, Mark A., Boerboom, Terrence J., Chandler, Val W., Mossler, John H., Runkel, Anthony C., and Setterholm, Dale R., 2011, S-21 Geologic Map of Minnesota-Bedrock Geology; Minnesota Geological Survey, State Map Series S-21. Scale 1:500,000.

NGMDB product
Counties Aitkin - Benton - Big Stone - Brown - Cass - Chippewa - Crow Wing - Douglas - Isanti - Kanabec - Kandiyohi - Lac qui Parle - McLeod - Meeker - Mille Lacs - Morrison - Murray - Nicollet - Otter Tail - Pine - Pope - Redwood - Renville - Sherburne - Sibley - Stearns - Stevens - Swift - Todd - Traverse - Wadena - Wright - Yellow Medicine