Nonesuch Shale facts for kids

Quick facts for kids Nonesuch Shale Stratigraphic range: Proterozoic
Native copper replaces cross-bedded sedimentary rocks of the Nonesuch Shale, White Pine mine, Upper Peninsula of Michigan
Type	Formation
Unit of	Oronto Group
Underlies	Freda Sandstone
Overlies	Copper Harbor Conglomerate
Location
Region	Michigan
Country	United States

The Nonesuch Shale is a special type of rock layer found underground. It's a Proterozoic geologic formation, which means it formed a very, very long time ago. You can see parts of it in Michigan and Wisconsin, United States. But scientists have found it stretches far underground, even reaching Iowa.

The Nonesuch Shale is made up of layers of shale, siltstone, and sandstone. These rocks formed in a large, ancient lake. It's about 150 to 210 meters thick. This rock layer sits on top of the Copper Harbor Conglomerate, which formed from river deposits. The Freda Sandstone, which also formed from river deposits, sits on top of the Nonesuch Shale. These three rock layers – Copper Harbor, Nonesuch, and Freda – together form something called the Oronto Group. The Nonesuch Shale is about 1.1 billion years old! It formed inside a huge crack in the Earth's crust called the Midcontinent Rift. The rocks in the Nonesuch Shale often contain organic carbon and pyrite, which is also known as "fool's gold."

Natural Resources in Nonesuch Shale

The Nonesuch Formation is important because it has been a big source of copper. People also think it might contain petroleum, which is another name for oil.

Copper Mining in the Nonesuch Shale

People first found copper in the Nonesuch Shale in the 1800s. Early attempts to mine it, like at the Nonesuch Mine in Ontonagon County, Michigan, didn't work very well. This was because the tiny pieces of native copper were hard to get out of the rock.

Later, the Copper Range Company opened the White Pine mine in Ontonagon County, Michigan, in 1955. This mine was very successful. The main copper minerals found there were chalcocite and native copper. This underground mine produced copper from the Nonesuch Shale for many years until it closed in 1995.

Oil Potential in the Nonesuch Shale

The Nonesuch Shale has enough organic carbon to be a possible source for petroleum. This means it could have formed oil. Scientists have even found oil from the Precambrian era (a very old time period) seeping into the White Pine copper mine in Michigan.

Exploration wells have been drilled to find Nonesuch-like rocks in Michigan, Wisconsin, and Iowa. However, no large amounts of oil or gas have been found yet.

Images for kids

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  Potholes in Nonesuch shale, Presque Isle River, Porcupine Mountains State Park, Upper Peninsula of Michigan