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Articles 541 - 570 of 626
Full-Text Articles in Geology
Applied Geology Of The Bismarck-Mandan Area, North Dakota, Gerald H. Groenewold
Applied Geology Of The Bismarck-Mandan Area, North Dakota, Gerald H. Groenewold
Theses and Dissertations
The Bismarck-Mandan area includes about 350 square miles located along both sides of' the Missouri River in south-central North Dakota. The area can be divided into two major physiographic divisions: the broad Missouri River floodplain and the nearly flat uplands which are dissected by minor streams. Geologic units in the area include Upper Cretaceous and lower Tertiary sandstone, siltstone, and shale and Quaternary sand, silt, clay, and gravel.
Expansion of residential areas around the cities of Bismarck and Mandan results in conflicts in land-use between agricultural, urban, and resource development. This study consists of detailed geologic maps and a series …
Geology Of Mclean County, North Dakota, John P. Bluemle
Geology Of Mclean County, North Dakota, John P. Bluemle
Theses and Dissertations
McLean County, in west-central North Dakota on the east side of the Williston Basin, is covered by 8,500 to 13,000 feet of Paleozoic, Mesozoic, and Cenozoic rocks, which dip to the west at low angles. The Tertiary Tongue River and Sentinel Butte Formations are widely exposed in McLean County, and the Tertiary Cannonball Formation is exposed in a few places. Glacial drift, assigned to a new formation, the Coleharbor Formation, occurs throughout the county and reaches a maximum thickness of at least 400 feet in certain preglacial valleys.
The eastern part of McLean County, part of the Missouri Coteau, is …
Gastropoda Of The Fox Hills Formation (Maestrichtian) Of North Dakota, J. Mark Erickson
Gastropoda Of The Fox Hills Formation (Maestrichtian) Of North Dakota, J. Mark Erickson
Theses and Dissertations
The Fox Hills Formation (Maestrichtian, Upper Cretaceous) in North Dakota contains a gastropod fauna of thirty-seven species. Five species, Neritina loganensis n. sp., Piestochilus feldmanni n. sp., Hercorhyncus (Hercorhyncus) hollandi n. sp., Remera? cvancarai n. sp., and Cancellaria siouxensis n. sp. , and genus, Dakotia, are newly described. Twenty-four genera in eighteen families representing four orders and two subclasses of Gastropoda are present. Eleven species in a like number of genera are newly reported from the Fox Hills For mation. Goniocylichna bisculpturata and Euspira rectilabrum occur in common with the gastropod fauna of the Ripley Formation of the Mississippi Embayment, …
Erosion And Sedimentation In Lake Ashtabula, Southeastern North Dakota, Darryll T. Pederson
Erosion And Sedimentation In Lake Ashtabula, Southeastern North Dakota, Darryll T. Pederson
Theses and Dissertations
Erosion along the shore of Lake Ashtabula and nearshore and offshore sedimentation were studied from May 1969 to December 1970. The lake, located in the southeastern part of North Dakota, was formed when the Baldhill Dam stopped the flow of the Sheyenne River in 1950. Maximum depth of the lake is 45 feet in the inundated river channel immediately above the dam. The lake is 27 miles long and ranges in width from 1/3 to 1/2 mile.
Shoreline erosion, measured at stations located at 100-foot intervals around the margins of the lake, was found to be a major source of …
Quantitative Geomorphology And Hydrology Of The Cass River Basin, New Zealand, Frank J. Schulte
Quantitative Geomorphology And Hydrology Of The Cass River Basin, New Zealand, Frank J. Schulte
Theses and Dissertations
The Cass River drainage basin is in the Southern Alps in the central part of the South Island of New Zealand. The Alps are composed of complexly folded greywacke which is still actively rising. The basin has been modified by several glacial advances during Pleistocene time.
The Cass basin has a temperate climate characterized by a steep precipitation gradient. Its vegetation includes plants of the forest grassland, shrubland, swamp, rock, and river-bed associations.
The Cass basin may be divided into four geomorphic areas: bedrock areas, high-angle fans, moderate-angle fans, and a low-angle fan. The bedrock areas consist of fractured greywacke; …
Concretions And Nodules In The Hell Creek Formation, Southwestern North Dakota, Gerald H. Groenwold
Concretions And Nodules In The Hell Creek Formation, Southwestern North Dakota, Gerald H. Groenwold
Theses and Dissertations
The Hell Creek Formation (Upper Cretaceous) in southwestern North Dakota consists of lagoonal and floodplain deposits and contains abundant concretions and nodules. Representative specimens of the concretions and nodules and their corresponding enclosing sediments were analyzed by thin section and by quantitative and qualitative x-ray diffraction methods.
Fourteen types of concretions and three types of nodules, classified according to shape and composition, have thus been defined. Concretionary types include calcareous sandstone lenses, “logs”, and irregular masses; sideritic sandstone lenses and irregular masses; calcareous and sideritic lignitic sandstone lenses; bone-cored rounded masses; coprolite-cored masses; jarosite bodies; pyrite spheres; baritic sandstone lenses; …
The Petroleum Geology Of The Midale Subinterval In North Central North Dakota, Kent A. Johnson
The Petroleum Geology Of The Midale Subinterval In North Central North Dakota, Kent A. Johnson
Theses and Dissertations
The Mississippian Midale subinterval is the basal unit of the Ratcliffe interval of the Madison Group. The Midale subinterval, an important petroleum producing unit in North Dakota, is a dolomitized limestone which is approximately 40 feet thick. A detailed study of 17 oil fields in north central North Dakota was conducted to determine the petroleum geology of the Midale subinterval. The study was done with the use of 563 mechanical well logs and core samples from 10 wells.
The anhydrite and dolomite units of the Rival subinterval, which underlie the Midale, and the Ratcliffe interval, which over lies the Midale, …
Groundwater Flow, Hydrochemistry, And Uranium Deposition In The Powder River Basin, Wyoming, J. Ladd Hagmaier
Groundwater Flow, Hydrochemistry, And Uranium Deposition In The Powder River Basin, Wyoming, J. Ladd Hagmaier
Theses and Dissertations
The relation between regional groundwater flow, hydrochemistry, and uranium distribution in the Powder River Basin indicates that uranium was deposited during the Tertiary Period in groundwater recharge areas where the groundwater changed from a sulfate-bicarbonate water to a bicarbonate-rich water.
The regional recharge and discharge areas of present-day groundwater-flow systems have about the same location as the recharge and discharge areas of the Tertiary groundwater-flow systems. The present-day groundwater is recharged in the eastern, western, and especially in the southern margins of the basin and is discharged in the valley of the Powder River, especially in the north. Flow nets …
Origin And Distribution Of Selenium In The Upper Cretaceous Niobrara And Pierre Formations, Northeastern North Dakota, Robert M. Novak
Origin And Distribution Of Selenium In The Upper Cretaceous Niobrara And Pierre Formations, Northeastern North Dakota, Robert M. Novak
Theses and Dissertations
High concentrations of selenium, often as much as 28 ppm, have been found in the bentonitic zones near the contact of the Niobrara and Pierre Formations of Cretaceous age in northeastern North Dakota. A 64-foot section in the Pembina Hills area reveals that the highest selenium content occurs in shale and marlstone beds adjacent to the bentonite beds which, themselves, contain comparatively little selenium. Higher concentrations of selenium were found in the brown shale than in the black, with a small variation in color making a big difference in selenium content.
The selenium content of the shale and marlstone drops …
Molluscan Paleontology Of The Pierre Shale (Upper Cretaceous), Bowman County, North Dakota, Kenneth F. Brinster
Molluscan Paleontology Of The Pierre Shale (Upper Cretaceous), Bowman County, North Dakota, Kenneth F. Brinster
Theses and Dissertations
The Pierre Shale of Campanian and Early Maestrichtian age in Bowman County, southwestern North Dakota, has an abundant molluscan fauna and 51 species are described herein. The 51 species consist of 1 species of scaphopod, 13 species in 11 genera of gastropods, 24 species' in 17 genera of bivalves, and 13 species in 6 genera of cephalopods.
The stratigraphy of the Pierre Shale in Bowman County was not compiled into a composite section because of the homogeneity of the shale, the lack of distinctive lithologic units, and the slumped condition of the shale. However, the biostratigraphic position of the Bowman …
Authigenic Analcite In The Golden Valley Formation Southwestern North Dakota, Marvin J. Furman
Authigenic Analcite In The Golden Valley Formation Southwestern North Dakota, Marvin J. Furman
Theses and Dissertations
Authigenic analcite constitutes up to about 60 percent of a massive, arksosic sandstone exposed on major buttes in the North Dakota Badlands. The analcite constitutes up to about 80 percent of a thin analcimolite bed at the top of the arkose unit. The analcite occurs as spherulites in the interstices of the arkose and as a cement in the analcimolite. Three types of spherulites are recognized: (1) spherulites with an internal radial structure; (2) spherulites with a massive center and a peripheral radial structure; and (3) spherulites lacking an internal radial structure or having a poorly-defined internal structure. The spherulites …
Rates Of Hillslope Lowering In The Badlands Of North Dakota, John R. Tinker Jr.
Rates Of Hillslope Lowering In The Badlands Of North Dakota, John R. Tinker Jr.
Theses and Dissertations
Measurements in a small drainage basin in the Little Missouri Badlands of western North Dakota indicate an average rate of hillslope lowering by slopewash of 0.41 inch per year on the west-facing hillslopes underlain by the Sentinel Butte Formation, 0.14 inch per year on the southwest-facing hillslopes underlain by the Tongue River Formation, and 0.11 inch per year on the northeast-facing hillslopes underlain by the Tongue River Formation. Soil creep occurs mainly on the Tongue River Formation and is mostly restricted to the northeast-facing hillslopes where the average rate of soil creep parallel to the hillslope surface is 0.23 inch …
Paleoenvironmental Reconstruction Of Late Quaternary Lacustrine Sediments (Seibold Site) In Southeastern North Dakota, William B. Bickley Jr.
Paleoenvironmental Reconstruction Of Late Quaternary Lacustrine Sediments (Seibold Site) In Southeastern North Dakota, William B. Bickley Jr.
Theses and Dissertations
The Seibold Site on the Missouri Coteau in northwest Stutsman County, North Dakota, contains a late Quaternary lacustrine deposit with a spectaculary preserved and diverse biota; more than 150 species occur, of which the mollusks and fish are figured and discussed in detail in this study. The stratigraphic sequence, in ascending order, is a follows: 1) pebbly silt; 2) clayey silt; 3) organic mud; 4) calcareous mud; 5) sandy silt and clay; 6) silty sand; and 7) sandy silt and clay.
The stratigraphic sequence and biota suggest a 5-phase history for the area during the last 11,000 years. During phase …
Quaternary Geology Of Rolette County, North Dakota, Dwight E. Deal
Quaternary Geology Of Rolette County, North Dakota, Dwight E. Deal
Theses and Dissertations
Rolette County contains approximately 942 square miles in north central North Dakota (Tps. 159-164 N., Rs. 69-73 W.) adjacent to the Canadian border. It includes the southeastern part of the Turtle Mountains and part of the glacial Lake Souris basin. Basic lithologies recognized in the surface sediments were bedded clay, silt, sand, and gravel; and three types of non-bedded diamicton. These were combined and, with bedding characteristics and organic content, formed 15 practical field mapping units. Geologically significant scarps and hill slopes were also mapped. The data collected is shown at a scale of 1 inch to 2 miles. The …
Groundwater Flow In Part Of The Little Missouri River Basin, North Dakota, Thomas M. Hamilton
Groundwater Flow In Part Of The Little Missouri River Basin, North Dakota, Thomas M. Hamilton
Theses and Dissertations
The Little Missouri valley in western North Dakota is deeply incised into slightly permeable Mesozoic and Cenozoic sediments. An evaluation of the groundwater flow in part of this valley was 'based on the present groundwater flow-system models. Abrupt changes in the hydrochemical facies have been explained relative to a continuous flow system.
The Little Missouri valley ls the discharge area of a regional groundwater flow system; it affects the potential distribution of the flow system for a minimum of 1.000 feet below the valley floor. The discharge area is approximately the same width as the valley floor and has a …
Petrography Of Xenolith Zones In The Black Face-Ames Plutons, Western San Juan Mountains, Colorado, Richard B. Moore
Petrography Of Xenolith Zones In The Black Face-Ames Plutons, Western San Juan Mountains, Colorado, Richard B. Moore
Theses and Dissertations
The middle to late Tertiary Black Face-Ames plutons are irregularly-shaped, intrusive bodies located in the San Miguel Mountains of southwestern Colorado. The Ames pluton is generally a composite sill; the Black Face pluton is an asymmetric laccol1th. The two plutons are probably joined at depth, and together they form a crudely annular outcrop pattern, open toward the west. The principal rock type within the plutons is granodiorite porphyry, although part of the Ames pluton consists of porphyritic rhyodacite.
Two major zones of xenoliths of Precambrian rock occur within the Black Face-Ames plutons; scattered xenoliths are found at widely separated locations. …
Surficial Lineaments And Their Structural Implications In The Williston Basin, A. Kirth Erickson
Surficial Lineaments And Their Structural Implications In The Williston Basin, A. Kirth Erickson
Theses and Dissertations
Lineaments of apparent geostructural origin are observable on air photos of the Williston basin. The pattern formed by these lineaments has the appearance of a broad system of interconnecting wrench faults such as occur on the adjacent Canadian shield. On this basis it is hypothesized that a broad system of left-lateral wrench faults may underlie the Williston basin region and possibly the entire continental foreland structural province.
Structures in the Williston basin are readily adaptable to this interpretation. The Nessen anticline appears to consist of a north-south realignment of a N. 40° E.- trending Precambrian high which was segmented by …
Fort Union (Paleocene) Mollusks From Southern Golden Valley And Southeastern Billings Counties, North Dakota, John J. Delimata
Fort Union (Paleocene) Mollusks From Southern Golden Valley And Southeastern Billings Counties, North Dakota, John J. Delimata
Theses and Dissertations
Nine molluscan species are known to occur in Tongue River Sentinel Butte sediments of parts of Billings, Golden Valley, and Slope Counties in southwestern North Dakota. Tongue River sediments contain all nine of the species which include: two unionids, Plesielliptio priscus (Meek and Hayden) and Rhabdotophorus senec tus (White); one corbulid, Bicorbula mactriformis (Meek and Hayden); and six viviparids, Viviparus retusus (Meek and Hayden), Viviparus trochiformis (Meek and Hayden), Campeloma nebrascensis (Meek and Hayden), Lioplacodes limnaefonnis (Meek and Hayden), Lioplacodes nebrascensis (Meek and Hayden), and Lioplacodes tenuicarinata (Meek and Hayden). Only five of these species (P. priscus, Q. nebrascensis, V. …
The Upper Red River Formation (Ordovician) In Western North Dakota, Harlan K. Friestad
The Upper Red River Formation (Ordovician) In Western North Dakota, Harlan K. Friestad
Theses and Dissertations
The upper Red River Formation in Western North Dakota consists of cyclic sedimentary rocks having four main porosity zones which contain most of the oil and gas found in the formation. It was divided into three distinct units that were traced throughout western North Dakota on mechanical logs. In ascending order these are the P, R, and F intervals which consist of alternating sequences of dolomites, limestones, and anhydrites. Facies changes, occur within the P interval both on a regional and a local scale, typically from dense limestones to porous dolomites.
The Kesson anticline and the basin hinge JJ.ne 1-1ere …
A Study Of Earth Science Teachers And Practices In North Dakota For The Academic Year 1968-1969, Howard C. Reith
A Study Of Earth Science Teachers And Practices In North Dakota For The Academic Year 1968-1969, Howard C. Reith
Theses and Dissertations
In the period between 1961-1964 the North Dakota department of Public Instruction initiated long overdue changes in the science curriculum for the seventh, eighth, and ninth grades of the public schools. Titese involved changes from general science to the life, earth, and physical sciences. During this same period there was a re vitalization of interest in earth science at the national level, with the public school enrollment rising from several thousand to well over one million.
Because of the rapid national growth in earth science enrollment, and the status of earth science in North Dakota, a study to determine the …
A Comparison Of The Late Wisconsinan Molluscan Fauna Of The Missouri Coteau District (North Dakota) With A Modern Alaskan Analogue, Samuel J. Tuthill
A Comparison Of The Late Wisconsinan Molluscan Fauna Of The Missouri Coteau District (North Dakota) With A Modern Alaskan Analogue, Samuel J. Tuthill
Theses and Dissertations
Study of forty fossiliferous sites in late Wisconsinan sediments from the Missouri Coteau district in central North Dakota has defined the molluscan fauna of the period of geologic time between 12,000 and 9,000 C14 years before the present. The fauna includes twenty-eight taxa of nonmarine gastropods and bivalves and is dominated by branchiates. The modern molluscan fauna of the Missouri Coteau district in North Dakota lacks four species which were resident in the late Wisconsinan and contains no unionids, one additional aquatic species, and is strongly dominated by pulmonate gastropods.
The geology of the Missouri Coteau has been interpreted as …
Washboard Moraines In Northeastern North Dakota, Dennis N. Nielsen
Washboard Moraines In Northeastern North Dakota, Dennis N. Nielsen
Theses and Dissertations
The descriptive term 11washboard moraine" has been applied to small transverse till ridges occurring in glaciated regions of North America. Washboard moraines have, in the past, been confused with similar transverse features such as ribbed moraines and De Geer moraines. No previous work had been done on washboard moraines in North Dakota prior to this study. Objectives of this study were to (1) map the distribution of washboard moraines in a selected study area,(2) describe the morphology and composition of washboard moraines, (3) determine the origin !or washboard moraines, and (4) compare data obtained in North Dakota with previously published …
Geologic And Limnologic History Of Glovers Pond, Northwestern New Jersey, J. Mark Erickson
Geologic And Limnologic History Of Glovers Pond, Northwestern New Jersey, J. Mark Erickson
Theses and Dissertations
Glovers Pond is a temperate, dimictic lake, 1.25 miles southwest of the town of Johnsonburg, Blairstown 7.5' Quadrangle, northwestern New Jersey. The Paleozoic Kittatinny, Jacksonburg, and Martinsburg Formations, in fault contact with each other, crop out in the vicinity of the lake. The lake has a maximum depth of 9.5 meters and occupies a glacially modified and dammed fault valley currently being infilled concentrically by .four types of sediment. Basim1ard these are: (1) peat, (2) marl, (3) "transitional", calcareous, organic-rich silt, and (4) gyttja. Glovers Pond is thermally and chemically stratified. The hypolimnion is undersaturated with CaCO3; tl1is prohibits deposition …
The Effects Of Groundwater Seepage On Stream Regimen : A Laboratory Study, Samuel S. Harrison
The Effects Of Groundwater Seepage On Stream Regimen : A Laboratory Study, Samuel S. Harrison
Theses and Dissertations
The effects of' groundwater seepage on the competence, bed rough ness, and water surface slope of small streams were studied in two laboratory fumes. The larger fume is 20 feet long, 3t feet wide, and 18 inches deep; the smaller flume is 12 feet long, 6 inches wide, and 10 inches deep. Both flumes are equipped so that groundwater seepage through the stream bed can be controlled and monitored.
In the absence of bedforms, upward (positive) seepage has little effect on stream competence or transport rate, even when quicksand conditions are reached. The decrease in effective grain density brought about …
The Geology Of The Newburg-South Westhope Oil Fields, Bottineau County, North Dakota, Hussein Marafi
The Geology Of The Newburg-South Westhope Oil Fields, Bottineau County, North Dakota, Hussein Marafi
Theses and Dissertations
The Newburg and South Westhope oil fields of the northeastern part of the Williston Basin are essentially one continuous secondary stratigraphic oil trap as determined by well log studies. The reservoir rocks in the two fields are carbonates present near the top of the Mississippian Ratcliffe interval and sandstone present in the basal unit of the Triassic Spearfish Formation. The two "pays” are separated by the post-Mississippian erosional unconformity which truncated the Ratcliffe beds.
The two fields are marked with depressions formed as a result of the dissolving of deep seated, presumably Devonian, salt beds and complementary gradual subsidence of …
The Postglacial Sedimentology Of Devils Lake, North Dakota, Edward Callender
The Postglacial Sedimentology Of Devils Lake, North Dakota, Edward Callender
Theses and Dissertations
The present sedimentary environment of Devils Lake, a Closed brackish lake in northeastern North Dakota, was investigated, and changes in the Holocene lacustrine environment are interpreted. Sediment samples from Main Bay of Devils Lake were analyzed for their physical, chemical and mineral ogical properties. Analytical data on surface sedimer.t were used to delineate the present sedimentary environment, while data on sediment from three cores were used to reconstruct the Holocene lacustrine history.
The dominant physical processes affecting the surface sediment are wave action and intermittent sediment influx through Big Coulee. The dominant chemical process, precipitation of calcium carbonate, is a …
Stratigraphy And Sedimentology Of The Tongue River Formation (Paleocene), Southeast Golden Valley County, North Dakota, Jack W. Crawford
Stratigraphy And Sedimentology Of The Tongue River Formation (Paleocene), Southeast Golden Valley County, North Dakota, Jack W. Crawford
Theses and Dissertations
The exposed Tertiary rock units in southeast Golden Valley County, North Dakota were measured and described with particular emphasis on the Tongue River Formation. Lithologic samples were collected and analyzed for total carbonate content, particle size, particle roundness, and mineral composition. In the area studied, the Tongue River Formation is 763 feet thick which is considerably thinner than in surrounding areas. The lower member of the Tongue River Formation is 313 feet thick and is composed of yellow-gray, very fine-grained sandstone, siltstone, claystone, shale, and lignite. The overlying Sentinel Butte Member is 450 feet thick and composed of yellow-brown, fine …
The Hell Creek Formation In North Dakota, Charles I. Frye
The Hell Creek Formation In North Dakota, Charles I. Frye
Theses and Dissertations
This paper is a discussion of the surface stratigraphy and petrology of the Hell Creek Formation in North Dakota and eastern Montana. Principal area of study included the Missouri Valley south of Bismarck, North Dakota; the Little Missouri Valley in Slope and Bowman Counties, southwestern North Dakota; the Yellowstone Valley near Glendive, Dawson County, Montana; and the type area of the Hell Creek Formation on Hell Creek and East Hell Creek, Garfield County, Montana on the south shore of the Fort Peck Reservoir.
Two and one-half summers were spent in the field measuring 72 stratigraphic sections, correlating between the measured …
The Surface Morphology Of A Small Drainage Basin In The North Dakota Badlands, J. Ladd Hagmaier
The Surface Morphology Of A Small Drainage Basin In The North Dakota Badlands, J. Ladd Hagmaier
Theses and Dissertations
To describe the surface morphology of a fourth order drainage basin located in the North Dakota Badland,, the writer made quanti tative application• of known descriptive techniques and morphological laws.
The surface configuration is a function of the study area's linear, areal, and relief properties and surface elements. The linear and areal properties are determined from maps showing the drainage basin 's surface geometry, the relief properties are determined from large-scale topographic maps of the area, and the surface elements are determined by direct field measurements of the ground slopes, surface materials, and vegetal coverage.
The surface geometry of the …
The Geology Of The Elliston Area, Western Montana, Thomas R. Walker
The Geology Of The Elliston Area, Western Montana, Thomas R. Walker
Theses and Dissertations
The Elliston area includes four townships located along the continental divide west of Helena, Montana on the northwest margin of the Boulder Batholith and within the Laramide disturbed belt. Strata ranging in age from Precambrian through recent are present, with all but the Ordovician, Silurian, and Triassic System& represented. The sedimentary rocks are mainly marine and continental carbonates, shales, and sandstones typical of a relatively stable shelf. The Precambrian Belt "Series" comprise the oldest rocks. The lower Cretaceous Blackleaf Formation is the youngest pre-Laramide unit. Post-Laramide sediments include fine-grained mid-Tertiary basin fills, terrace gravels, a moraine, and a mantle of …