This report presents uranium and other elemental data resulting from the Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Dubois NTMS quadrangle in Idaho and Montana. Totals of 1024 water samples and 1600 sediment samples were collected from 1669 locations in the Dubois quadrangle. Water samples were taken at streams, springs, and wells; sediment samples were collected from streams and springs.

Introduction: During the year 1952-1953, research on the Boulder batholith program was largely devoted to basic mineralogy studies of the "siliceous reef" and, to the extent possible at that time, the "base metal" deposits.

Introduction: This preliminary report is an attempt to correlate all of the available information having a bearing on the geology of the uraniferous deposits and to set forth such theories and recommendations as may be deduced at this stage.

From introduction: This report describes the program of research on mineralogy and petrography of certain uraniferous vein deposits in the Boulder batholith of western Montana.

Abstract: The Free Enterprise property is located in the Boulder mining district, Jefferson County, Montana. Secondary uranium minerals occur here in small irregular concentrations in and adjacent to a narrow silicified fracture zone in quartz monzonite.

Abstract: A low-level airborne radioactivity survey of parts of Beaverhead and Madison Counties in southwestern Montana was undertaken from June 6 to October 14, 1955. Flying centered around the Ruby Range-Sweetwater Basin area and concentrated on the Precambrian metamorphic complex and Tertiary lake-bed sediments. No commercial uranium deposits were discovered, and no extensions were found of the few known small occurrences. Five areas of high background detected through the survey were investigated on the ground.

From introduction: This is one of a series of three reports on airborne radioactivity surveys in the United States. The reports contain the 185 airborne anomaly maps issued by the U. S. Atomic Energy Commission as a result of the AEC's aerial surveying program conducted from March 1952 to June 1956; two ground reconnaissance maps of Utah also are included. Most of the reconnaissance was done in the western United States.

Abstract: An airborne radiometric survey of parts of the east flank of the Big Horn Mountains was begun on June 23, and completed on August 27, 1952. An area of approximately 250 square miles was covered, and only two anomalies were found in the entire area. Flight lines were arranged in accordance with the geology of the area, particular attention being given to formations the stratigraphic equivalents of which are known to be uranium bearing in other areas. Two additional zones of radioactivity were found by ground investigation, but assays from both the ground and the airborne discoveries showed no economic uranium deposits.

From abstract: Between mid-May and late June 1976, 3409 water and water-transported sediment samples were collected from 1781 locations spread over an approximate 17 000 kilometer area of northwestern Montana. All of the samples were analyzed for total uranium at the LASL, using standardized procedures and rigorous quality controls--the waters by fluorometry and the sediment (and those waters with >10 parts per billion uranium) by delayed-neutron counting methods.

The objective of the study was to evaluate the favorability for potential uranium resources in Tertiary and related strata. Past studies indicate that the Tertiary basins in southwestern Montana are worthy of further investigation because (1) several basins contain a thick sequence of continental sedimentary rocks, (2) several basins are near possible granitic source rocks that have known uranium occurrences, and (3) some of the Montana basins are geologically similar to basins in Wyoming that are host to important sandstone-type deposits. This study focuses on sedimentary rocks of Tertiary age, but includes some rocks of Late Cretaceous and Pleistocene ages. In some areas only a portion of the total Tertiary sedimentary section could be studied because of poor surface exposures and limited subsurface information.

From introduction: This report presents data gathered in a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) conducted by the Los Alamos Scientific Laboratory (LASL) in southwestern Montana. The HSSR was initiated by the US Department of Energy (DOE) to outline areas favorable for uranium exploration by examining uranium concentrations in natural waters and stream sediments.

From summary: This report contains data collected during a geochemical survey for uranium in the Ashton National Topographic Map Series (NTMS) quadrangle of eastern Idaho, southwestern Montana, and northwestern Wyoming (Fig. 1) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide lydrogeochemical and Stream Sediment Reconnaissance (HSSR).

From summary: This report contains data collected during a geochemical survey for uranium in the Billings National Topographic Map Series (NTMS) quadrangle of south-central Montana (Fig. 1) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

This volume contains information and survey results pertaining specifically to the Cut Bank NTMS 1:250,000-scale Quadrangle, Montana, one of a group of 12 such quadrangles in Arizona, Idaho, Montana, New Mexico, South Dakota, and Washington included in an aerial radiometric and magnetic reconnaissance survey. Information concerning the instrumentation and methods used in data acquisition, processing, and interpretation is presented in Volume 1 of this final report.

From introduction: This volume contains information and survey results pertaining specifically to the Shelby NTMS 1:250,000 scale Quadrangle, Montana, one of a group of 12 such quadrangles in Arizona, Idaho, Montana, New Mexico, South Dakota, and Washington included in an aerial radiometric and magnetic reconnaissance survey. General information concerning the instrumentation and methods used in data acquisition, processing, and interpretation is presented in Volume 1 of this final report.

From introduction: This volume contains information and survey results pertaining specifically to the Havre NTMS 1:250,000 scale Quadrangle, Montana, one of a group of 12 such quadrangles in Arizona, Idaho, Montana, New Mexico, South Dakota, and Washington included in an aerial radiometric and magnetic reconnaissance survey. General information concerning the instrumentation and methods used in data acquisition, processing, and interpretation is presented in Volume 1 of this final report.

From introduction: This volume contains information and survey results pertaining specifically to the Lewistown NTMS 1:250,000 scale Quadrangle, Montana, one of a group of 12 such quadrangles in Arizona, Idaho, Montana, New Mexico, South Dakota, and Washington included in an aerial radiometric and magnetic reconnaissance survey. General information concerning the instrumentation and methods used in data acquisition, processing, and interpretation is presented in Volume 1 of this final report.

From introduction: This volume contains information and survey results pertaining specifically to the Choteau NTMS 1:250,000 scale Quadrangle, Montana, one of a group of 12 such quadrangles in Arizona, Idaho, Montana, New Mexico, South Dakota, and Washington included in an aerial radiometric and magnetic reconnaissance survey. General information concerning the instrumentation and methods used in data acquisition, processing, and interpretation is presented in Volume 1 of this final report.

Appendix containing tables to accompany a report on aerial radiometric and magnetic reconnaissance survey of the Havre Quadrangle.

Appendix containing tables to accompany a report on aerial radiometric and magnetic reconnaissance survey of the Shelby Quadrangle.

Appendix containing tables to accompany a report on aerial radiometric and magnetic reconnaissance survey of the Lewistown Quadrangle.

This report contains aerial gamma-ray and magnetic survey maps of the Choteau Quadrangle.

Appendix containing single-record and averaged-record data listings to accompany a report on aerial radiometric and magnetic reconnaissance of the Ritzville Quadrangle.

Appendix containing tables to accompany a report on aerial radiometric and magnetic reconnaissance survey of the Cut Bank Quadrangle.