Geology and Ground Water: Garden County, Nebraska

All of Garden County is underlain by the Brule Formation. This formation is tightly cemented and yields sufficient water to wells only in areas where the siltstone has been fractured. In most places the Brule Formation forms an impermeable seal that prevents water from moving downward from the overlying aquifers. The Arikaree Group is unimportant as an aquifer in the county, but the younger Ash Hollow Formation is important, particularly beneath the Cheyenne Tableland. Most, if not all, of the domestic and livestock wells on the tableland tap this aquifer. The thickness of the Ash Hollow Formation is 100 feet or less beneath much of the tableland except in the southeastern part of the county in the Ash Hollow Creek area, where it is more than 200 feet thick, and in the southwestern part of the county in the Rush Creek area, where it is more than 300 feet thick. In most of the area of the Cheyenne Tableland, the supply of ground water is adequate for domestic and livestock watering needs but not for irrigation. The Ash Hollow Formation is more than 700 feet thick in the northeastern part of the county beneath the Sandhills and contains an abundant supply of water. It has not been used extensively as a source of water because the overlying younger deposits also contain an abundant supply of water

Geology of the Ogallala/High Plains Regional Aquifer System in Nebraska: Field Trip No. 6

This guide is mostly figures with a reference section containing some of the pertinent literature on the Cenozoic geology we will see over the next four days. We will make all 17 stops if the weather is reasonably good and the roads are passable. On the first day, April 29, we will try to get to stops 1–5, the more distal parts of the Ogallala and younger deposits in Nebraska. On April 30, we will try to visit stops 6–9. Stops 10–15, in areas closer to the sediment sources of the Ogallala and some of the younger units, will be examined on May 1. Stops 16–17 will be made on our return trip to Lincoln. Stop 1. Todd Valley. Our first stop will be north of North Bend, Nebraska, on the surface of the Todd Valley fill to see some of the Quaternary geomorphology of eastern Nebraska and to review some aspects of Quaternary stratigraphy in the eastern part of the state. Stop 2. Ashfall Fossil Beds State Historical Park. This is one of the truly extraordinary mammalian vertebrate fossil localities in North America. Stop 3. Long Pine Formation. Skinner and Hibbard (1972) described the units in this area and originally placed them in the early Pleistocene. The Keirn, Long Pine, Duffy, and Pettijohn formations have subsequently been placed in the Pliocene and are equivalent in age to the Broadwater Formation of western Nebraska. Stop 4. Valentine Formation. This is a short stop to see some of the sands of the Valentine Formation and the Niobrara River valley. Stop 5. Valentine and Ash Hollow formations. Skinner and Johnson (1984) subdivided these formations into a number of members, some of which can be seen exposed in road cuts and natural exposures northeast of the city of Valentine, Nebraska. Stop 6. Snake River Falls. The geologic section exposed here was illustrated and described by Skinner and Johnson. Part of the Caprock Formation of the Ash Hollow forms the resistant ledge over which the Snake River falls. Stop 7. Box Butte Tablelands, Niobrara Valley, and Pine Ridge. Swinehart and others (1985) have described the stratigraphy of this area in general and have placed in the Ogallala Group several units previously included by some workers in the Hemingford Group. Stop 8. Carhenge. Considered folly by some, this piece of folk art by a local resident is intended to resemble the British stone circle, Stonehenge. Entering the North Platte Valley. Stop 9. Duer Ranch. We will walk over parts of the area and see spectacular examples of Ogallala Group gully fills, Ash Hollow Formation sands and gravels filling channels and basal inner channels of the Broadwater Formation (=Long Pine). Stop 10. Multiple volcanic ash deposits in the Ash Hollow Formation south of Broadwater, Nebraska. Diffendal (1984b) and Swinehart and others (1985) published maps showing the distribution of volcanic ash beds in the area. Stop 11. Greenwood Canyon south of Bridgeport, Nebraska. A general stratigraphic section of the rocks exposed in this area was published in Stout and others (1971). Subsequently, Diffendal (1984b) studied the area and, among other things, found multiple volcanic ash beds in the Ash Hollow Formation of the Ogallala Group. Stop 12. Early Quaternary fluvial deposits of Pumpkin Creek valley. If you look once again at figure 4, you will see that I have depicted a tributary to the North Platte River in the general position of Pumpkin Creek valley on the early Pleistocene maps, but have not shown it on the map of Pliocene drainages. This stop is at a gravel pit that yielded fossils of early Pleistocene mammals. Stop 13. Faden and Van Pelt ranches—Ash Hollow Formation valley fills. At Faden Ranch, the basal Ash Hollow Formation fills inner channels like those of the basal Broadwater Formation on Duer Ranch. On the Van Pelt Ranch, we will look at part of one valley fill, tributary gully fills, opal beds, caliches, and other interesting features. Stop 14. Exposures of the typical Kimball south of Kimball, Nebraska. This stop includes the supposed stratigraphically highest parts of the so-called Kimball Formation of the Ogallala. Stop 15. Exposures of the typical Sidney Gravel near Sidney, Nebraska. We will look at compositional differences of this supposed unit, now included in an expanded Ash Hollow Formation. Stop 16. Ash Hollow. Ash Hollow is the type area of the Ash Hollow Formation. Stop 17. Type area of the Ogallala Group. This is the poorest type area of any we have seen. It has no exposed base and the top is erosional

Fun in a Kansas salt mine

Most 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

LETTER FROM THE EDITOR

There I was, happily enjoying retirement, getting to read what I wanted, and come to the office when I wanted. Then in late February 2004, the Director of the Center for Great Plains Studies (CGPS) at the University of Nebraska-Lincoln, Dr. Jim Stubbendieck, called me and asked if I would consider accepting the job of editor of Great Plains Research. I considered the offer and quickly accepted. In the brief time that I have been on the job I have gotten to know some of the staff at the CGPS and have found them to be easy to work with and very helpful. I look forward to continuing to help them to produce the fine journal, Great Plains Research, and to improve its already excellent quality. I encourage all scholars working on studies in the Great Plains to consider submitting their manuscripts to us for possible publication in our journals

Cheyenne County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 17

In 1930, the Conservation and Survey Division (CSD) of the University of Nebraska and the U.S. 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. Also included are logs of test-holes drilled by cooperators with the South Platte Natural Resources District. The maps in this report show the location of all test holes drilled in the county since 1934 (Figure la–e). 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 the 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 Cheyenne 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 Cheyenne County, descriptions of strata done in earlier test-hole reports are included with some revised formation information in this report

Gully, Scour Hole, and Pothole Development at the Base of the Gering Formation (Miocene?), Southeastern Banner County, Nebraska

Several 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

Review of \u3ci\u3eThe Ends of the World: Volcanic Apocalypses, Lethal Oceans, and Our Quest to Understand Earth\u27s Past Mass Extinctions\u3c/i\u3e by Peter Brannen

In his new best-selling book, Peter Brannen, award-winning science writer, takes you on a fascinating trip through the run-up to the endCretaceous extinction event and the K-Pg (Cretaceous/ Paleogene) boundary, formerly called the K -T (Cretaceous/Tertiary) boundary. ... Brannen interviewed many scientists who studied these events and went on field trips with them to major Cretaceous sites and to those where earlier and later extinction events happened. He presents clear explanations of what is known and not known about all of these events in a largely error-free book. Brannen details the other four big extinction events in geologic history: the End-Ordovician (about 443 million years ago); the Late Devonian (374 and 359 million years ago); the really big one, the End-Permian (252 million years ago); and the End-Triassic (201 million years ago). You might think that all these extinctions were triggered by the effects of bolide impacts, but if you did you would be wrong. Some scientists have named the current age the \u27\u27Anthropocene;\u27 which I think, as some others do, began in 1712 CE with the invention of the steam engine. Those scientists think that our impact will be as big on life as the other big extinction events. Let\u27s hope that they are wrong, but please read Peter Brannen\u27s book to get some better idea than you have currently of what has gone on in the past and what is happening today

Gully, Scour Hole, and Pothole Development at the Base of the Gering Formation (Miocene?), Southeastern Banner County, Nebraska

Several 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

Fossils on the Floor in the Nebraska State Capitol: A Coloring and Activities Book

The Nebraska State Capitol is a wonderful place. This building is home to great treasures of art owned by the people of Nebraska. The floor of the Capitol Rotunda has beautiful works of art. Maybe you have seen this art. Small pieces of two kinds of rocks make pictures of people, their tools, the natural resources they used, and pictures of fossil animals and plants. These kinds of pictures are called mosaics [moe ZAY icks]. The animals and plants follow one another in a curved ribbon around the floor. In that ribbon of pictures are many kinds of fossil animals and plants including some of the dinosaurs. This book will tell you some things about these fossils. The story of how the floor was made begins many years ago. In 1927 a famous paleontologist and teacher at the University of Nebraska in Lincoln heard that the new Capitol would have mosaics of fossil animals and plants like ones found in Nebraska and nearby states. That paleontologist was Professor Erwin H. Barbour [bar BORE], the third director of the University of Nebraska State Museum, also called Morrill Hall or Elephant Hall. Professor Barbour was asked to draw pictures of fossil plants and animals for artist Hildreth Meière [HILL dreth mee AIR] to copy. Professor Barbour was also a very talented artist. He drew many large colored pictures of fossil plants and animals and sent them to Miss Meière, who lived in New York City. She used some of these drawings to make some of the mosaic pictures of fossils on the Rotunda floor. People thought that all of Professor Barbour’s drawings were lost. A few years ago some were found and given to the people who work in the State Capitol. Now some of the beautiful pictures that Professor Barbour drew on tissue paper are preserved for the future. He used pastels, color sticks like crayons, to draw the pictures. He drew colored dinosaurs in 1927, long before anyone else thought that these animals had colored skins. Professor Barbour also drew pictures of fossil animals with a pen and black ink

Great Plains geology -- A personal journey

From 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