Nonesuch Shale

Nonesuch Shale

The Nonesuch Shale is a Proterozoic geologic formation that outcrops in Michigan and Wisconsin, United States, but has been found by drill holes to extend in the subsurface as far southwest as Iowa.

The Nonesuch is a lacustrine sequence of shale, siltstone, and sandstone, 150 to 210 m thick, that conformably overlies the alluvial Copper Harbor Conglomerate and is conformably overlain by the fluvial Freda Sandstone.[1] Together, the Copper Harbor, Nonesuch, and Freda make up the Oronto Group.[2] The Nonesuch is Middle Proterozoic, with an estimated age of approximately 1.1 billion years. It was deposited in the Midcontinent Rift.[3] The Nonesuch beds contain common organic carbon and pyrite.


Natural resources

The Nonesuch Formation has been a major source of copper, and is considered a prospective source of petroleum.


Copper was discovered in the Nonesuch in the 1800s, but early mining efforts, such as those at the Nonesuch Mine in Ontonagon County, Michigan, failed because of the difficulty of recovering the fine grains of native copper.

The Copper Range Company opened the White Pine mine in Ontonagon County, Michigan, in 1955. The principal ore minerals were chalcocite and native copper.[4] The underground mine produced copper from the Nonesuch Shale until it closed in 1995.


The Nonesuch Shale has sufficient organic carbon content (greater than 0.5%) to be considered a potential sourcebed for petroleum. Oil identified as Precambrian has been found seeping into the White Pine copper mine in Michigan.[5] Exploration wells have been drilled to Nonesuch-equivalent sediments in the rift basin in Michigan, Wisconsin, and Iowa, but no petroleum deposits have been discovered.


  1. ^ William C. Kelly and Gail K. Nishioka, "Precambrian oil inclusions in late veins and the role of hydrocarbons in copper mineralization at White Pine," Geology, May 1985, p.334-337.
  2. ^ Scott W. Imbus and others, "Organic geochemistry and sedimentology of middle Proterozoic Nonesuch Formation - hydrocarbon source rock assessment of a lacustrine rift deposit," in Lacustrine Basin Exploration, Tulsa, Okla.: American Association of Petroleum Geologists, p.197-208
  3. ^ Albert B Dickas, “Midcontinent rift system: Precambrian hydrocarbon target,” Oil and Gas Journal, 15 October 1984, p.151-159.
  4. ^ Walter S. White and James C. Wright, "Sulfide-mineral zoning in the basal Nonesuch Shale, northern Michigan," Economic Geology, November 1966, p.1171-1190.
  5. ^ J.A. Seglund, “Midcontinent Rift continues to show promise as petroleum prospect,” Oil and Gas Journal, 15 May 1989, p.55-58.

See also

External links

Iowa Geological Survey: Exploring the Midcontinent Rift, PDF file, retrieved 27 December 2008.

Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Nonesuch Mine — Nonesuch stamp mill foundation remains. Ruins of equipment used in th …   Wikipedia

  • Copper mining in Michigan — While it originated thousands of years earlier, copper mining in Michigan became an important industry in the 19th and early 20th centuries. Its rise marked the start of copper mining as a major industry in the United States. Contents 1 Geology 2 …   Wikipedia

  • Oronto Group — The Oronto group is a thick group of arkose sandstone and shale located beneath the Bayfield Group in northern Wisconsin,[1] and believed to extend into Minnesota.[2] Because it is almost entirely red in color and highly tilted, it is considered… …   Wikipedia

  • Midcontinent Rift System — Geological map of North America showing (in white) the Midcontinent Rift, here labeled Keweenawan Rift. Lake Superior occupies the apex of the rift. The Midcontinent Rift System (MRS) or Keweenawan Rift is a 2,000 km (1,200 mi) long… …   Wikipedia

  • Copper Range Company — This article is about the former US mining company. There is a current Australian company named Copper Range Limited. Cuprite on dendritic native copper, Champion Mine. Size 6.6 x 3.8 x 3.2 cm …   Wikipedia

  • performing arts — arts or skills that require public performance, as acting, singing, or dancing. [1945 50] * * * ▪ 2009 Introduction Music Classical.       The last vestiges of the Cold War seemed to thaw for a moment on Feb. 26, 2008, when the unfamiliar strains …   Universalium

  • furniture — furnitureless, adj. /ferr ni cheuhr/, n. 1. the movable articles, as tables, chairs, desks or cabinets, required for use or ornament in a house, office, or the like. 2. fittings, apparatus, or necessary accessories for something. 3. equipment for …   Universalium

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”