1,721,103 research outputs found
Fun in a Kansas salt mine
Full text linkMost people probably do not know that salt deposits hundreds of feet thick lie buried beneath large parts of western Kansas, western Oklahoma and a small part of the northeastern Texas Panhandle. Native Americans and early European explorers found that where the salt deposits came near the land surface (for, example north of Hutchinson, Kansas) salt is dissolved by ground water and increases the salinity of rivers, streams, springs and ponds. This salty water was used as a salt source by these peoples. The Hutchinson Salt, a 275 million-year-old Middle Permian deposit, was discovered in an exploratory drill hole in 1887. The Carey Salt Company began mining the purer, lower part of the 325-foot-thick salt beneath South Hutchinson in 1923. The Hutchinson Salt Company purchased the mine in 1990 and currently processes between 500,000 and 750,000 tons of salt per year, mostly sold for use as rock salt and cattle supplements. Mining continues today, north of a large mined out area leased long-term to Strataca: Kansas Underground Salt Museum and to Underground Vaults and Storage, Inc., which uses its 1,665,000 ft2 of leased space to store such things as documents, films, art works and other items under constant humidity of 40% and temperatures ranging from 68-73° F. Strataca has year-round tours of parts of the abandoned mine as well as a gift shop and a museum featuring mining history and equipment as well as artifacts from and information about the UV&S stored items. Open dates, times and tour costs can be found at the Strataca web site. The tour, my third salt mine so far, was a lot of fun and may be the experience of a lifetime for many people who have never previously been in a mine. My group of geologists had a four-hour tour and got to see many things that the public does not. As we prepared to walk back to the lifts to take us back to the surface, we were passed by many families with children off on a Sunday afternoon adventure. The kids were having a lot of fun. One caution -- the tour is not for the claustrophobic
River Potholes: Modern and Ancient
Full text linkA river pothole is a cylindrical, bowl-shaped, or irregular hollow that is usually deeper than wide. It is formed in the rocky bed of a stream by either the grinding action of sediment whirled around by stream eddies or the force of fast flowing water. Potholes usually have spirally grooved surfaces. Their widths and depths range from a few inches to many feet. Potholes on the floor of the Susquehanna River near Columbia, Pennsylvania, for example, are large enough to hold objects the size of a small car.
Potholes generally are formed in fairly homogeneous rock by streams that at least periodically have high discharges. Long grooves running parallel or nearly parallel to the stream flow are often carved into the bedrock floor of the channel and may lead from one pothole to another. A wonderful example of these related features occurs on the channel floor of the Niobrara River at Norden Bridge in north-central Nebraska. As the river continues to erode its channel the shapes and sizes of the grooves and potholes change.
Another fantastic example of pothole development occurs at Boiling Pots Park on the southwest outskirts of Hilo, Hawaii. Here a stream has carved a valley through several sheets of hardened lava rock or basalt. The stream plunges over successively exposed layers of this basalt, each of which are up to 20 feet thick. A pothole or series of potholes in each layer of rock crossed by the stream produces a series of circular pools that at times of low water are arranged like a string of beads
Great Plains geology -- A personal journey
Full text linkFrom graduate school in 1962 to now, I achieved my goals and became a geologist and professor, travelling and doing research in the Great Plains and western Central Lowland physiographic provinces, and looking at geology in exotic places like the UK, China, Australia and New Zealand. Fast forward to 2013. I had enough experience and expertise on Great Plains geology by then that I was asked to write a short book of about 35,000 words on the geology of the Great Plains by the director of the Center for Great Plains Studies at the University of Nebraska, Dr Richard Edwards. After visiting and studying sites in Alberta and Saskatchewan in Canada, and in south-western Texas that I had not previously studied, I started working on the book now titled Great Plains Geology that is reviewed in this issue of Deposits on ,.the page opposite. I may be wrong, but I think that few people from the UK have much of a mental image of the Great Plains or know its boundaries. Certainly, that is true of most of our citizens in the USA. The area of land included in the Great Plains has been much debated since the late 1800s, when the physiographic region was defined and its area probably drawn for the first time on a map by the second director of the US Geological Survey, John Wesley Powell (Fig. 1; 1895). Powell only included the part of the Great Plains in the US on his map, but wrote that the place extended north into the Canadian prairie provinces of Alberta and Saskatchewan, and south into a small part of northern Mexico. I have included descriptions of some sites in those areas of the Great Plains in my book
Ecoregions of Nebraska and Kansas
Full text linkEcoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources; they are designed to serve as a spatial framework for the research, assessment, management, and monitoring of ecosystems and ecosystem components. Ecoregions are directly applicable to the immediate needs of state agencies, including the development of biological criteria and water quality standards, and the establishment of management goals for nonpoint-source pollution. They are also relevant to integrated ecosystem management, an ultimate goal of most federal and state resource management agencies. The approach used to compile this map is based on the premise that ecological regions can be identified through the analysis of the patterns of biotic and abiotic phenomena that reflect differences in ecosystem quality and integrity (Wiken, 1986; Omernik, 1987, 1995). These phenomena include geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another regardless of the hierarchical level. A Roman numeral hierarchical scheme has been adopted for different levels of ecological regions. Level I and level II divide the North American continent into 15 and 52 regions, respectively (Commission for Environmental Cooperation Working Group 1997). At level III, the continental United States contains 104 regions (United States Environmental Protection Agency [US EPA], 2000). However, depending on the objectives of a particular project, ecoregions may be aggregated within levels of the hierarchy for data analysis and interpretation. Explanations of the methods used to define the US EPA’s ecoregions are given in Omernik (1995), Griffith and others (1994), and Gallant and others (1989).
Albers equal area projection; Standard parallels 38° N and 42° N
PRINCIPAL AUTHORS: Shannen S. Chapman (Dynamac Corporation), James M. Omernik (US EPA), Jerry A. Freeouf (USFS), Donald G. Huggins (KBS), James R. McCauley (KGS), Craig C. Freeman (KBS), Gerry Steinauer (NGPC), Robert T. Angelo (KDHE), and Richard L. Schlepp (USDA, NRCS). COLLABORATORS AND CONTRIBUTORS: Steven R. Walker (NDEQ), Kenneth R. Bazata (NDEQ), Sharon W. Waltman (USDA, NRCS-National Soil Survey Center [NSSC]), William J. Waltman (USDA, NRCS-NSSC), Roger Kanable (USDA, NRCS), Steven C. Schainost (NGPC), Craig Engelhard (USDA, NRCS), James W. Merchant (Center for Advanced Land Management Information Technologies [CALMIT], University of Nebraska, Lincoln [UNL]), Virginia L. McGuire (USGS), Chris Mammoliti (KDWP), James L. Stubbendieck (UNL), David A. Mortensen (UNL), Thomas Wardle (Nebraska Forest Service), David T. Lewis (UNL), Robert F. Diffendal Jr. (Nebraska Conservation and Survey Division-Nebraska Geological Survey) and Jeffrey A. Comstock (OAO Corporation). This project was partially supported by funds from the U.S. Environmental Protection Agency’s Office of Water, Biological Criteria Program.
Reverse side and supplementary 1-page versions are attached
Geomorphic and Structural Features of the Alliance 1º × 2º Quadrangle, Western Nebraska, Discernible from Synthetic-Aperture Radar Imagery and Digital Shaded-Relief Maps
No full textThe digital shaded-relief map of the United States and the synthetic-aperture radar map of the Alliance Nebraska 1º x 2º area prepared by the U.S. Geological Survey (USGS) in the former case and for the USGS in the latter show oriented landforms and lineaments in northwest Nebraska. Parallel and subparallel hills and valleys developed on different geologic materials ranging from shales through sandstones to loess and eolian sand appear to be wind erosional features subsequently modified by running water. The long axes of these hills and valleys generally trend between N40 W and N50 W. Similar features also occur across major areas of the Great Plains from Montana southeast at least to Kansas. Most of the lineaments are in two sets, one trending northeast, the other northwest. There are some east-west and north-south trending lineaments in the western part of the quadrangle, some circular features in the northwest, and some chevronlike lineaments in the north-central part. Some lineaments appear to coincide wholly or in part with known faults in western Nebraska or with extensions of faults in east-central Wyoming into northwest Nebraska. All other lineaments are probably reflections of either jointing or, more likely, of faulting. Additional field work will be needed to verify which of these two, if either, is responsible for any particular lineament
Geometries and General Features of Some Cenozoic Valleys and Valley Fills, Western Nebraska
Full text linkPortions of Tertiary and Quaternary valleys and valley fills have been exhumed by recent stream erosion at many sites in western Nebraska. Paleovalleys vary from narrow, steep-sided, high gradient tributary gullies less than 0.1 km wide to broad, flat-floored valleys produced by lateral erosion. Segments of valley floors may be nearly smooth in the case of a Quaternary example, or may be very irregular with potholes and other deep scour features. Paleovalley sides, when exposed, are often steeply sloping, and approaching or possibly going beyond the vertical where the valleys have been eroded into the Brule Formation. Paleovalleys range in straightness from those that are nearly straight to those with broadly meandering forms. Both single and seemingly anastomosing paleovalleys occur in the area. Paleovalley fills, including channel fills, vary in composition from alluvial deposits derived completely from local sources to sediments eroded by streams heading in the Rocky Mountains or carried by winds from volcanic sources in the Rocky Mountains or areas farther west. Fills deposited along valley sides include blocks of rock up to one meter or more in intermediate diameter moved only a few meters downslope from their sources
Redington Quadrangle, Nebraska—Banner and Morrill Counties, 7.5 Minute Series (Topographic)
Full text linkRedington Quadrangle, Nebraska—Banner and Morrill Counties
7.5 minute series (topographic), scale 1:24000
103°15\u27 to 103°22\u2730
41°30\u27 to 41°37\u2730
Twb, Qalc, Toa, IW, Tamch, Lower Whitney, Upper Whitney
April 5, 198
Gully, Scour Hole, and Pothole Development at the Base of the Gering Formation (Miocene?), Southeastern Banner County, Nebraska
Full text linkSeveral sediment-filled paleovalleys belonging to the Arikaree Group of Miocene (?) age occur in southeastern Banner County, Nebraska. One gully and a main paleovalley exhibit, respectively, erosional features like those in modern gullies in the area and like those on the bedrock floors of modern straight streams carrying an appreciable sediment load. Scour holes and a pothole on the valley floor of the main paleovalley are similar to those produced experimentally on the bed of a straight stream
Deuel County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 25
Full text linkIn 1930, the Conservation and Survey Division (CSD) of the University of Nebraska and the United States Geological Survey began a program of cooperative groundwater studies in Nebraska. Since then test drilling by use of rotary drilling equipment has been an integral part of that program. This report contains logs of all the test holes drilled in the county under the program as well as those drilled by the Conservation and Survey Division with financial assistance from other government agencies.
The map in this report shows the location of all test holes drilled in the county since 1942.
Present techniques of test-hole logging and sampling include use of drilling mud suitable to drilling conditions, timing by stopwatch of the drilling of each 5-foot increment of depth, and removal of all cuttings from the test hole at intervals of 5 feet or less. During the drilling of the hole, cuttings from each interval are examined immediately; samples representing each 5-foot interval and each recognizable change in material are retained. After samples are washed, they are described lithologically and the color is evaluated by comparison with standard color charts. The samples then are dried, stored, and cataloged. All samples are processed and kept on open file in the offices of Conservation and Survey Division, 113 Nebraska Hall, University of Nebraska-Lincoln, 68588-0517.
Beginning in September 1951, some of the test holes have been logged electrically. Geophysical logs (e-logs) often can be used to determine formation boundaries more precisely than by field sampling, especially where differences in rock types from one formation to another occur at the boundary. Figure 2 is an example of geophysical logs of a test hole from Deuel County with formation boundaries shown. Departures of the curves from the center lines generally indicate that the geologic unit is becoming coarser grained. A notation on each test hole log indicates if geophysical logs are part of the original test hole data in the CSD office in Lincoln.
This publication is one of a series being issued to make more readily available the record of test holes drilled since 1930. The series of publications is made on a county basis and includes, with some exceptions, logs of all test holes drilled in each of the counties. The logs have not been reviewed for conformance with editorial standards and nomenclature. In the case of Deuel County, descriptions of strata done in earlier test hole reports are included with some revised formation information in this report
Nebraska, USA: Wonderful Fossils, Natural History Museums and Public Art Depicting Fossils
Full text linkNebraska is known by vertebrate palaeontologists as the place in North America where there is a very complete Cenozoic geologic record of mammalian evolution over the last thirty-five million years or so. All you have to do is visit any of the many major natural history museums in the USA and in many countries around the world, including the UK, to see fossil skulls, articulated skeletons and large slabs of rock containing bones of fossil mammals from Nebraska to verify this assertion. Nebraska is also the site of Cretaceous rocks containing the oldest known Cretaceous fossil flower and many other parts from fossil plants. It also contains dinosaur footprints and trackways, and skeletons of marine plesiosaurs, mosasaurs and large marine fish, as well as terrestrial and marine invertebrate fossils and marine microfossils. Upper Carboniferous rocks exposed at the surface in parts of southeastern Nebraska have yielded fossil terrestrial plant fossils, marine stromatolites and other marine plant fossils, marine invertebrates, fish and even some fossil bones of amphibians and early reptiles. All in all, Nebraska is a vast storehouse of wonderful fossils that continues today to yield them up to collectors, both professional and amateur. These fossils can be found on both private and public lands, and in state and federal parks and museums
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