FREDA SANDSTONE
Below is an outcrop photo of
the Freda Sandstone at its type locality - the town of Freda, Michigan.
The Freda is the top unit in the upper Mesoproterozoic Oronto Group.
Below the Freda is fine-grained siliciclastics of the Nonesuch Shale and
coarse-grained siliciclastics (+ some basalt lava flows) of the Copper Harbor
Conglomerate. The Freda itself is dominated by reddish fluvial arkosic
sandstones.
Stratigraphy & Age: Freda Sandstone, upper
Oronto Group, upper Mesoproterozoic, ~1.07-1.08 billion years.
Freda Sandstone - lakeshore cliff outcrop
at Freda, southern shore of Lake Superior, Houghton County, UP of Michigan, USA
(see
map).
Freda Sandstone (field of view ~5.3 cm
across) - a fluvial arkosic sandstone. The orangish specks are K-feldspar
sand grains.