DIGITAL DATABASE FOR THE QUATERNARY GEOLOGIC MAP OF THE GLASGOW 1 X 2 QUADRANGLE, MONTANA OPEN-FILE REPORT 2012-1217 By David S. Fullerton, Roger B. Colton, and Charles A. Bush 2012 Open-file Report 2012-1217 ABSTRACT The Glasgow quadrangle encompasses approximately 16,084 km2 (6,210 mi2). The northern boundary is the Montana/Saskatchewan (U.S./Canada) boundary. The quadrangle is in the Northern Plains physiographic province and it includes the Boundary Plateau, Peerless Plateau, and Larb Hills. The primary river is the Milk River. The map units are surficial deposits and materials, not landforms. Deposits that comprise some constructional landforms (for example, ground-moraine deposits, end-moraine deposits, and stagnation-moraine deposits, all composed of till) are distinguished for purposes of reconstruction of glacial history. Surficial deposits and materials are assigned to 23 map units on the basis of genesis, age, lithology or composition, texture or particle size, and other physical, chemical, and engineering characteristics. It is not a map of soils that are recognized in pedology or agronomy. Rather, it is a generalized map of soils recognized in engineering geology, or of substrata or parent materials in which pedologic or agronomic soils are formed. Glaciotectonic (ice-thrust) structures and deposits are mapped separately, represented by a symbol. The surficial deposits are glacial, ice-contact, glaciofluvial, alluvial, lacustrine, eolian, colluvial, and mass-movement deposits. Residuum, a surficial material, also is mapped. Till of late Wisconsin age is represented by three map units. Till of Illinoian age is also represented locally but is widespread in the subsurface. This map was prepared to serve as a database for compilation of a Quaternary geologic map of the United States and Canada (scale 1:1,000,000). Letter symbols for the map units are those used for the same units in the Quaternary Geologic Atlas of the United States map series. DISCLAIMERS This database, identified as OFR 2012-1217, has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty, expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute such warranty. The U.S.Geological Survey shall not be held liable for improper or incorrect use of the data described and/or contained herein. Any use of trade, product or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain,it also contains copyrighted material as noted in the text. Permission to reproduce copyrighted items for other than personal use must be secured from the copyright owner. CONTACT INFORMATION Charles A. Bush U.S. Geological Survey (303) 236-4723 cbush@usgs.gov CONTENTS README.txt OF12_1217_508.pdf glasgow.txt (metadata) The following ARC/INFO files are included in glasgowGIS.zip: gis data: Glasgow_geology.gdb glasgow_geo_ply feature class includes polygons that are map units and open water Explanation of fields: UNIT--Refers to the type of polygon and is either the map unit symbol, Lake or River. DESCRIPTION--A description of the deposits and materials that make up the map units; blank where not applicable. See map.pdf for full unit descriptions. AGE--Refers to the age of the map unit and is one of the following: HOLOCENE AND LATE WISCONSIN; HOLOCENE, LATE PLEISTOCENE AND MIDDLE PLEISTOCENE; HOLOCENE AND PLEISTOCENE; QUATERNARY AND TERTIARY; LATE WISCONSIN; ILLINOIAN; PRE-QUATERNARY; or blank where not applicable. (See table below.) glasgow_geo_line Explanation of fields: DESCRIPTION--Refers to the type of arc and is one of the following: Contact, Shoreline, or Map Boundary glasgow_glac_line Explanation of fields: DESCRIPTION describes the feature represented by the line and contains one of the following: LIMIT OF LATE WISCONSIN GLACIATION; LIMIT OF LATE WISCONSIN GLACIATION-Inferred; LIMIT OF ILLINOIAN GLACIATION; LIMIT OF ILLINOIAN GLACIATION-Inferred; LIMIT OF A GLACIAL READVANCE, OR POSITION OF A SIGNIFICANT STILLSTAND OF AN ICE MARGIN; LIMIT OF A GLACIAL READVANCE, OR POSITION OF A SIGNIFICANT STILLSTAND OF AN ICE MARGIN-Inferred; MINOR MORAINES; SOUTHEAST LIMIT OF RESIDUAL ERRATIC GLACIAL BOULDERS ON DISSECTED BEDROCK SURFACES; COVERED BY DISINTEGRATION RESIDUUM; ICE-MOLDED OR ICE-SCOURED LANDFORM-Linear drumlin, rock drumlin, or fluting; ESKER; BURIED BEDROCK VALLEYS OF THE ANCESTRAL MISSOURI AND MUSSELSHELL RIVERS glasgow_point is a point feature class indicating the locations of important stratigraphic sections Explanation of fields: DESCRIPTION describes the location of IMPORTANT STRATIGRAPHIC SECTIONS and contains one of the following: IMPORTANT STRATIGRAPHIC SECTION-No. 1, Loring section; IMPORTANT STRATIGRAPHIC SECTION-No. 2, Anderson Ranch section; IMPORTANT STRATIGRAPHIC SECTION-No. 3, Glasgow Air Force Base site glasgow_geo_ply_ Frequency - frequency table glasgow_geo_ply_ Frequency1 - frequency table glasgow_geo_ply_ Frequency2 - frequency table glasgow_geo_ply_ Frequency3 - frequency table glasgow_glac_line_ Frequency - frequency table glasgow_glac_line_ Frequency1 - frequency table glasgowAV geo_net_arc.shp (.dbf/.prj/.sbn/.sbx/shp./.shp.xml/.shx) geo_net_polygon.shp (.dbf/.prj/.sbn/.sbx/shp./.shp.xml/.shx) gal_lin_arc.shp (.dbf/.prj/.sbn/.sbx/shp./.shp.xml/.shx) sect_pntn_point.shp (.dbf/.prj/.sbn/.sbx/shp./shp./.shp.xml/.shx) INSTRUCTIONS AND DOCUMENTATION FOR U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 2012-1217 To access the data: The data files can be downloaded via the web from: http://pubs.usgs.gov/ofr/2012/1217/ The main product is a Portable Document Format (.pdf) map, which requires Adobe Acrobat for viewing. Acrobat software runs on a variety of systems, and is available for download free of charge from Adobe at http://www.adobe.com.