From Purpose and Scope: "The Gillette 1º x 2º Quadrangle, Wyoming, and South Dakota was evaluated to find volumes of rock considered favorable for uranium deposits and which could contain at least at 100 mt tons U3O8 with an average grade of 0.01 percent U3O8 or more. All geologic environments to a depth of 1,500 m (5,000 ft) evaluated through the use of surface investigations and subsurface information."

Results of reconnaissance surveys of the Lewistown quadrangle to determine the likelihood of uranium deposits of the area, and additional information about the location and classification of any deposits.

Discussing occurrences of uranium in the Lewistown Quadrangle

Discussing statistical analyses of the Lewiston Quadrangle

From Introduction: "The Bozeman Quadrangle is south-central Montana was evaluated for geologic environments capable of containing uranium deposits to a depth of 1500 m (5,000 ft.). Most rock types and geographic areas were investigated by surface traverse, and hydrgeochemical data were collected from available well sites."

From Introduction: "The Butte Quadrangle, Montana (Fig. 1), was evaluated to identify geologic environments and delineate areas that exhibit characteristics favorable for the occurrence of uranium deposits. Each environment was categorized as favorable, unfavorable, or evaluated according to criteria established in Mickle and Mathews (eds., 1978)."

This report follows the evaluation of uranium resources in the Ekalaka 1°x 2° Quadrangle, Montana and North and South Dakota to a depth of 1,500 m (5,000 ft) using available subsurface geologic information.

From Introduction: "The Elk City Quadrangle (1º by 2º), Idaho and Montana, was evaluated to identify and delineate geologic environments that exhibit characteristics favorable for the occurrence of uranium deposits."

Results of reconnaissance surveys of the Hamilton quadrangle to determine the likelihood of uranium deposits of the area, and additional information about the location and classification of any deposits.

Discussing occurrences of uranium in the Hamilton Quadrangle

From Purpose and Scope: "The Billings Quadrangle (2º), Montana and Wyoming, was evaluated to identify geologic units and to delineate areas that exhibit characteristics favorable for uranium deposits that could contain at least 100 tons U3O8 in rocks with an average grade of not less than 100 ppm U3O8. Surface and subsurface data were used to evaluate all geologic environments to a depth of 1500 m (5,000 ft)."

From Introduction: "The Sandpoint Quadrangle (Fig. 1) was evaluated to define areas with geologic environments favorable for uranium deposits. Environments were evaluated on the basis of surface investigations because few subsurface data were available."

Results of reconnaissance surveys of the Havre quadrangle to determine the likelihood of uranium deposits of the area, and additional information about the location and classification of any deposits.

Discussing the occurrence of uranium in the Havre Quadrangle

Discussing oil well logs for the Havre Quadrangle

From Introduction: "The Sheridan NTMS 1º by 2º Quadrangle (Fig. 1) in north-central Wyoming was evaluated to identify geologic environments that have characteristics favorable for uranium deposition. Only environments to a depth of 1500 m have been evaluated for this project."

From Introduction: "The Kalispell Quadrangle, in northwestern Montana (Fig. 1), was evaluated to identify geologic environments and delineate areas that exhibit characteristics favorable for uranium deposits. Favorable environments, as determined by surface and subsurface investigations, are those that could contain uranium deposits of at least 100 tons U3O8 at an average grade not less than 100 ppm U3O8."

From Purpose: "The White Sulphur Springs Quadrangle, in west-central Montana between latitude 46º and 47ºN. and longitude 110º and 112ºW. (Fig. 1), was evaluated to identify geologic environments and delineate areas that exhibit characteristics favorable for uranium deposits. Favorable environments, as determined by surface and subsurface investigations, are those that could contain uranium deposits of at least 100 tons U3O8 at an average not less than 100 ppm U3O8."

Abstract: This report lists the machine-readable data files developed for the Madison Limestone and Northern Great Plains Regional Aquifer System Analysis (RASA) projects that are stored on magnetic tape and available from the U.S. Geological Survey. Record format, file content, and size are given for: (1) Drill-stem-test data for Paleozoic and Mesozoic formations; (2) geologic data from the Madison Limestone project; (3) data sets used in the regional simulation model; (4) hydraulic-head data for the Lower and Upper Cretaceous aquifers; and (5) geologic data for Mesozoic formations of the Northern Great Plains.

From introduction: In 1978 the U.S. Geological Survey began a 4-year study of aquifers in the northern Great Plains. The purpose of this map, which is a product of that study, is to show the altitude of the top of the "Dakota sandstone" (drillers' term).

From introduction: In 1978 the U.S. Geological Survey began a 4-year study of aquifers in the northern Great Plains. The purpose of this map, which is a product of that study, is to show the altitude of the top of the Eagle Sandstone.

Introduction: In 1978 the U.S. Geological Survey began a 4-year study of aquifers in the northern Great Plains. The purpose of this map, which is a product of that study, is to show the altitude of the top of the Fox Hills-lower Hell Creek aquifer. Other maps show the total thickness (Feltis, 1982a). cumulative thickness of sandstone (Feltis, 1982b), and potentiometric surface of water (Levings, 1982) of the Fox Hills-lower Hell Creek aquifer. These maps are part of a series that describes the geology and potentiometric surface of selected rock units of Jurassic or younger age in the plains area of Montana.

From introduction: In 1978 the U.S. Geological Survey began a 4-year study of aquifer in the northern Great Plains. The purpose of this map, which is a product of that study, is to show the altitude of the top of the Judith River Formation.

Introduction: In 1978 the U.S. Geological Survey began a 4-year study of aquifers in the northern Great Plains. The purpose of this map, which is a product of that study, is to show the altitude of the top of the Lakota Formation and equivalent rocks. Other maps show the total thickness (Feltis, 1982a), cumulative thickness of sandstone (Feltis, 1982b), and potentiometric surface of water (Levings, 1982) in the Lakota Formation and equivalent rocks. These maps are part of a series that describes the geology and potentiometric surface of selected rock units of Jurassic or younger age in the plains area of Montana.