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Articles 751 - 780 of 830
Full-Text Articles in Earth Sciences
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 …
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, …
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 …
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. …
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 …
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 …
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 …
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 …
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 …
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 …
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 …
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 …
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 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 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 …
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 Newcastle Formation In The Williston Basin Of North Dakota, Mark Reishus
The Newcastle Formation In The Williston Basin Of North Dakota, Mark Reishus
Theses and Dissertations
The Lower Cretaceous Newcastle Formation of the Black Hills has been traced, through the use of well logs, from near the type section in eastern Wyoming into the subsurface of the Williston Basin. In the Basin, the Newcastle Formation is a very fine to medium grained, gray to white, quartzose sandstone, which overlies the Skull Creek Shale and underlies the Mowry Shale. In area where the Newcastle is absent the overlying and underlying shales cannot be separated and here are referred to as “undifferentiated Mowry-Skull Creek”.
Newcastle deposition occurred mainly in the eastern one-third and western quarter of North Dakota. …
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 …
A Stratigraphic And Sedimentologic Analysis Of The Tongue River And Sentinel Butte Formations (Paleocene), Western North Dakota, Chester F. Royse Jr.
A Stratigraphic And Sedimentologic Analysis Of The Tongue River And Sentinel Butte Formations (Paleocene), Western North Dakota, Chester F. Royse Jr.
Theses and Dissertations
The Tongue River-Sentirel Butte contact has been regarded by many workers as a vague color boundary of minor extent within a relatively homogeneous sequence of Paleocene strata. Consequently, the Sentinel Butte has come to be regarded as a subordinate unit of the ”Tongue River Formation. As defined in report, the contact is a distinctive horizon between two discrete lithogenetic units. It characterized by three criteria: a horizon (HT Butte bad) &t the top of the Tongue River sequence; a. basal sandy unit in the Sentinel Butte sequence, and a marked change in color between buff yellow Tongue River sediments below …
Time And Soil Development On Lateral Moraines, Martin River Glacier, South-Central Alaska, John R. Tinker Jr.
Time And Soil Development On Lateral Moraines, Martin River Glacier, South-Central Alaska, John R. Tinker Jr.
Theses and Dissertations
During the summer of 1966, eighteen soil profiles on a series of 21 lateral moraines, were studied to ascertain the relationship of time to soil development. The moraines are located on Charlotte Ridge on the south margin of the Martin River Glacier in south-central Alaska. The elevation of the highest moraine is approximately fifteen hundred feet and is located 800 feet above the present level of the glacier.
To determine the direct effect of time on soil formation, the remaining soil forming factors were kept constant; the soil pits were located so that relief, exposure, and vegetation of the sites …
Ore Controls And Formation Of The Ore-Bearing Structures In The Idarado Mines, San Miguel And Ouray Counties, Colorado, S. R. Sanjines
Ore Controls And Formation Of The Ore-Bearing Structures In The Idarado Mines, San Miguel And Ouray Counties, Colorado, S. R. Sanjines
Theses and Dissertations
Two major ore-bearing veins were studied on two levels in the Idarado mine, on the northwestern flank of the San Juan Mountains of southwestern Colorado. The Argentine vein, striking N. 10°-20° W. and dipping 75°-85° W., and the Cross vein, striking N. 45°-50° W. and dipping 50° W. represent the two systems to which all productive veins of the mine belong. Although not formed simultaneously, all veins represent mid-Tertiary mineralization associated with volcanism that formed the San Juan Mountains. Vein minerals are galena, sphalerite, chalcopyrite, silver (probably as sulfides), and gold in a gangue of pyrite, quartz, calcite and epidote. …
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 …
Hydrogeology Of The Shell Creek Area, Mountrail County, North Dakota, Robert G. Willson
Hydrogeology Of The Shell Creek Area, Mountrail County, North Dakota, Robert G. Willson
Theses and Dissertations
A field study of the geology and hydrology of the Shell Creek area in southeastern Mountrail County, North Dakota, was made during 1966 in order to determine the hydrogeology of the area. Six lithostratigraphic and lithologic units were mapped. Samples were analyzed for grain size and mineralogy. Those units are the Fort Union Group, the “Lostwood” slightly-gravelly loam, the “Lostwood” sand-gravel, the “Lostwood” silt-clay, the “Little-Knife Formation”, and the “Coteau Formation”. Mine average maximum slope and drainage integration units were used to map the morphology of the area.
There are four magnitudes of flow systems observed in the Shell Creek …
Bivalvia And Paleoecology Of The Fox Hills Formation (Upper Cretaceous) Of North Dakota, Rodney M. Feldmann
Bivalvia And Paleoecology Of The Fox Hills Formation (Upper Cretaceous) Of North Dakota, Rodney M. Feldmann
Theses and Dissertations
The bivalve fauna of the Fox Hills Formation, Maestrichtian, of North Dakota was studied in an attempt to modernize the nomenclature of known bivalves, describe new forms, interpret the relationships of members of the formation, and establish the paleoecological setting in which the Fox Hills was deposited.
The Fox Hills Formation crops out in Logan, Emmons, Sioux, Morton, Burleigh, Kidder, Pierce, McHenry, Bottineau, and Bowman counties in North Dakota. It is best exposed along the Missouri River in south-central North Dakota. Traditionally, the formation has been subdivided into four members, all of which are exposed in the type area of …
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 …
Recent Fluvial Geology In Western North Dakota, Thomas M. Hamilton
Recent Fluvial Geology In Western North Dakota, Thomas M. Hamilton
Theses and Dissertations
The thesis here abstracted was written under the direction of Lee Clayton and approved by Walter L. Moore -and John R. Reid as members of the examining connnittee, of which Mr. Clayton was chairman.
In western North Dakota many drainage channels that are incised into valley fill are characterized by steep, unvegetated sides. Many such channels contain actively eroding scarps. The origin of these scarps is most frequently related to increased water velocity causing accelerated erosion on a steepened reach of the valley flat.
The principal mechanism of scarp migration is soilfall which is initiated by undercutting of the scarp …