Denham Formation

Lithic sandstone (reworked saprolite), marble, and mica schist (youngest detrital zircons greater than 2,000 Ma).
State Minnesota
Name Denham Formation
Geologic age Paleoproterozoic
Lithologic constituents
Sedimentary > Clastic > Sandstone (Bed)Lithic sandstone (reworked saprolite)
Metamorphic > Schist > Mica-schist
Metamorphic > Metasedimentary > Metacarbonate > Marble
Comments Part of the Mille Lacs and North Range Groups in the fold-and-thrust belt of the Penokean orogen (twice-deformed). Twice-deformed metasedimentary rocks at the apparent base of the Animikie basin. Part of the Geon 18 intrusions and supracrustal rocks (syn- to late Penokean orogenesis).

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 - Mille Lacs - Pine