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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 …

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

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 …

Surficial Lineaments And Their Structural Implications In The Williston Basin, Kirth 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 …

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 …

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.

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 …

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 …