Nebraska, USAi

Regional Level Types
Nebraska	State
USA	Country

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Nebraska's surface geology is exclusively unconsolidated sediments or sedimentary bedrock. Bedrock ranges from Pennsylvanian to Cretaceous age in the eastern and central parts of the state, and Cenozoic sediments in the west. Only about 13% of the state's surface is underlain by by shallow or exposed bedrock, and about 70% of that is in the Panhandle. The remaining 30% of the area with shallow or exposed bedrock lies is in the north-central, northeastern, and southeastern fringes, leaving a large area in the middle where bedrock is seldom found, except by deep drilling (Joeckel et al, 2018). During the Pleistocene Epoch, at least two large continental ice sheets covered the eastern part of the area that became Nebraska with glacial till and outwash sediments up to ~ 50 meters thick. In the west-central part of the state, the Sand Hills Region, is made up of wind-shaped sand dunes, and covers nearly 20,000 square miles.

The main literature reference for mineral collectors is Educational Circular No. 2: "Minerals and Gemstones of Nebraska" (available online, see links below). Nebraska’s first State Geologist, Erwin Barbour, summed up the mineral situation as follows: “It must be remembered that the rocks of Nebraska are level, undisturbed sediments which are usually deeply blanketed and concealed from view by sand and soil. There are no mountains, no crystalline rocks, no uplifts, dikes or veins, accordingly there are few minerals throughout this great territory. The common minerals in nature are few in number, simple in composition, and are easily identified and remembered” (Barbour, 1915). Many collectors are not deterred however, and there are some striking specimens of celestine, quartz, calcite and barite that have been found in Pennsylvanian and Permian rocks in the southeast. And in the northwest, various varieties of chalcedony (e.g. agate, opal, petrified wood, and chalcedony pseudomorphs after gypsum) are found in or weathering from Cenozoic rocks. Glacial and alluvial deposits around the state also yield varieties of chalcedony, including Lake Superior and Fairburn-type agates.

Nebraska is rich in fossils, notably Cenozoic vertebrates. Nebraska’s “bone beds” are among the richest in the world, and skeletons of titanotheres, oreodonts, rhinoceroses, horses, hogs, bovines, elephants, camels, deer, and carnivores can be seen in museums in the state and several other major U.S. museums. Nebraska has the most complete record of elephant evolution of any state. Elephant fossils have been found in 90 of Nebraska’s 93 counties.

The State Museum's vertebrate paleontology collection is one of the largest university collections in the United States, with over 1.5 million specimens. The Nebraska fossil record covering the last 35 million years of North American history is especially well documented. (Links below provide information on fossils and the university collections). In addition to the State Museum in Lincoln, excellent exhibits of fossils can be seen at the Ashfall State Historical Park in Antelope County, and the Agate Fossil Beds National Monument in Sioux County.

Nebraska has more river miles that any other state in the U.S. Collecting of agates, jasper, petrified wood, fossils and other alluvial material is a popular pastime all over the state. Sand and gravel are important natural resources occurring in many parts of Nebraska. Principal sources are Recent and Pleistocene deposits associated with streams and their floodplains, and also upland terrace deposits of Pleistocene and Tertiary age. (Burchett, 1971).

Commodity List

This is a list of exploitable or exploited mineral commodities recorded from this region.

Mineral List

Mineral list contains entries from the region specified including sub-localities

81 valid minerals.

Rock Types Recorded

Rock list contains entries from the region specified including sub-localities