Physical Sciences and Mathematics Commons^™

Salinity, Radon, And Radon Precursors In The Soils Of Grand Forks County, North Dakota, Kevin L. Solie

Theses and Dissertations

High levels of indoor radon have been observed in many areas of the Red River Valley and particularly in Grand Forks County of North Dakota. Data from the University of North Dakota (UND) Radon Monitoring Facility indicated more than 80% of the dwellings tested had radon levels greater than the United States Environmental Protection Agency (USEPA) action limit of 4 pCi/l. High radon levels may pose a health threat (USEPA, 1986) to valley residents.

A review of existing data indicates that areas of the Red River Valley in North Dakota with elevated soil salinity also exhibit higher equivalent uranium (eU) …

Prey Selectivity By Naticid Gastropods From Tertiary Sediments Of The United States Coastal Plain, Robert N. Sickler

Theses and Dissertations

Previous studies have shown that naticid gastropod predators are highly selective of prey species in accordance with the Kitchell et al. (1981) cost-benefit model. In addition, earlier studies have demonstrated selectivity of drillhole siting and intraspecific prey size. This study focuses on prey selectivity by Oligocene naticid gastropods and is used to test Vermeij's (1987) hypothesis of escalation. The hypothesis of escalation states that biologic hazards have increased during the Phanerozoic and that organisms have either had to adapt to these hazards or face possible extinction (Vermeij, 1987). Naticid predation on molluscan assemblages is one of several examples used to …

Depositional Environments And Paleogeography Of The Winnipeg Group (Ordovician), Williston Basin, North Dakota, Jonathan B. Ellingson

Theses and Dissertations

The Winnipeg Group (Upper Ordovician) unconformably overlies the Deadwood Formation (Cambrian - Lower Ordovician) over most of North Dakota, except in the extreme eastern part, where it lies directly on Precambrian basement rocks. The Winnipeg is conformably overlain by the Red River Formation (Upper Ordovician). The Winnipeg reaches a maximum thickness of 448 feet (136.6 m) in the center of the basin, Williams County. The Winnipeg Group consists of three formations, in ascending order, the Black Island, Icebox, and Roughlock Formations. The Black Island Formation is, herein, formally divided into the Hawkeye Valley and the Garland Members.

The Hawkeye Valley …

Depositional History, Environments Of Deposition, And Hydrocarbon Potential Of The Newcastle Formation (Lower Cretaceous) Of Eastern North Dakota, Gerald G. Mccloskey

Theses and Dissertations

The Newcastle Formation (Albian) in North Dakota is composed primarily of fine grained sandstone, mudstone and shale. This study examined the Newcastle within the eastern two thirds of North Dakota, with the goal of determining the various depositional environments, the depositional history, and the hydrocarbon potential of the unit. A total of 2191 geophysical well logs and 21 lithologic cores were examined. Isopach maps of the Newcastle Formation and the Skull Creek Shale were generated, as was a structural top map of the Mowry Shale.

The depositional history of the unit is directly linked to the regression and subsequent transgression …

The Paleoecologic Significance Of Paleocene Palynomorph Assemblages From The Ludow, Slope, And Cannonball Formations, Southwestern North Dakota, Timothy J. Kroeger

Theses and Dissertations

Paleoenvironment exerted control on the distribution of 133 palynomorph taxa from the Ludlow and Slope Formations and Boyce and Three V Tongues of the Cannonball Formation (Fort Union Group, I Paleocene) of southwestern North Dakota. The strata represent fluvial deltaic systems that prograded eastward into the Cannonball Sea. Depositional environments include distributary channels, crevasse splays, crevasse-splay feeder channels, lignite-producing swamps and/or marshes, lakes, brackish to slightly brackish bays, lake and bay fills, and marshes

Paleoenvironmentally sensitive palynomorph taxa were identified by subjective examination of pollen diagrams and objective analysis using detrended correspondence analysis. Two paleoenvironmentally restricted palynomorph associations were recognized. …