|Baldwin Dam on the Sheyenne River in North Dakota. This river contains detrital gold that is weathered from conglomerates that were washed down from the Black Hills of South Dakota|
Saturday, April 16, 2011
Gold Occurrences in North Dakota
Detrital gold has been found in two different occurrences within the state of
. One of these occurrences is in northern North Dakota over 500 miles north of Manitoba that was brought in by the glacier that receipt of about 12,000 years ago. This formed placer deposits that are scattered across the state. The other gold that is found in North Dakota had an entirely different origin coming from conglomerate that was washed down from the Black Hills of South Dakota. It was subsequently eroded, and brought to the surface by the action of the North Dakota where it is now found as cemented gravel. Although the deposits of this sort are most common in the bed of the Sheyenne River it is also found as a cap rock on many of the buttes and ridges found throughout the state. Sheyenne River
Conglomerate and other sedimentary rocks are not especially rare places in which detrital gold is found. This is gold that has weathered out of older crystalline rocks and carried away by the action of running water to be deposited as placer gold in stream gravel that later become cemented in place for me in a fossilized placer deposit. The largest gold deposit on earth, the Witwatersrand of South Africa, is gold in a conglomerate matrix. It is been recently discovered that the source for the gold in this deposit came from outwash in braided stream channels from an ancient mountain range. The geologists who pinpointed the origin of this gold used the half-life of an isotope of iridium that was found with the gold. This also explains why the gold was found in stringers throughout the deposit.
It is common to find uranium associated with this type of deposit as well as rare earth elements (REE). It is older of this type that is mind that
Elliot Lake, for its uranium content. This is one of the largest uranium deposits in Ontario North America.
The first gold rush in
was in an area called glacial North Dakota . This discovery of gold was made about 6 miles north of Lake Souris in Fort Ransom . They are still finding small amounts of placer gold there today. It's like the old saying goes, gold is where you find it. Ransom County