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T. R. Brandt

Publications and source records attributed to T. R. Brandt.

4 recordsLinked to original sources

Generalized surficial geologic map of the Pueblo 1° x 2° quadrangle, Colorado

Fifty-three types of surficial geologic deposits and residual materials of Quaternary age are described in a pamphlet and located on a map of the greater Pueblo area, in part of the Front Range, in the Wet and Sangre de Cristo Mountains, and on the plains east of Colorado Springs and Pueblo. Deposits formed by landslides, wind, and glaciers, as well as colluvium, residuum, alluvium, and others are described in terms of predominant grain size, mineral or rock composition (e.g., gypsiferous, calcareous, granitic, andesitic), thickness, and other physical characteristics. Origins and ages of the deposits and geologic hazards related to them are noted. Many lines drawn between units on our map were placed by generalizing contacts on published maps. However, in 1997-1999 we mapped new boundaries as well. The map was projected to the UTM projection. This large map area extends from near Salida (on the west edge), eastward about 107 mi (172 km), and from Antero Reservoir and Woodland Park on the north edge to near Colorado City at the south edge (68 mi; 109 km).

Colorado

Surficial geologic map of the greater Omaha area, Nebraska and Iowa

Geologic mapping, in support of the USGS Omaha-Kansas City Geologic Mapping Project, shows the spatial distribution of artificial-fill, alluvial, eolian, and glacial deposits and bedrock in and near Omaha, Nebraska. Artificial fill deposits are mapped chiefly beneath commercial structures, segments of interstate highways and other major highways, railroad tracks, airport runways, and military facilities, and in landfills and earth fills. Alluvial deposits are mapped beneath flood plains, in stream terraces, and on hill slopes. They include flood-plain and stream-channel alluvium, sheetwash alluvium, and undivided sheetwash alluvium and stream alluvium. Wind-deposited loess forms sheets that mantle inter-stream areas and late Wisconsin terrace alluvium. Peoria Loess is younger of the two loess sheets and covers much of the inter-stream area in the map area. Loveland Loess is older and is exposed in a few small areas in the eastern part of the map area. Glacial deposits are chiefly heterogeneous, ice-deposited, clayey material (till) and minor interstratified stream-deposited sand and gravel. Except for small outcrops, glacial deposits are covered by eolian and alluvial deposits throughout most of the map area. Bedrock is locally exposed in natural exposures along the major streams and in quarries. It consists of Dakota Sandstone and chiefly limestone and shale of the Lansing and Kansas City Groups. Sand and gravel in flood plain and stream-channel alluvium in the Platte River valley are used mainly for concrete aggregate. Limestone of the Lansing and Kansas City Groups is used for road-surfacing material, rip rap, and fill material.

Iowa, Nebraska

Generalized surficial geologic map of the Denver 1° x 2° quadrangle, Colorado

Thirty-nine types of surficial geologic deposits and residual materials of Quaternary age are described and mapped in the greater Denver area, in part of the Front Range, and in the piedmont and plains east of Denver, Boulder, and Castle Rock. Descriptions appear in the pamphlet that accompanies the map. Landslide deposits, colluvium, residuum, alluvium, and other deposits or materials are described in terms of predominant grain size, mineral or rock composition (e.g., gypsiferous, calcareous, granitic, andesitic), thickness of deposits, and other physical characteristics. Origins and ages of the deposits and geologic hazards related to them are noted. Many lines between geologic units on our map were placed by generalizing contacts on published maps. However, in 1997-1999 we mapped new boundaries, as well. The map was projected to the UTM projection. This large map area extends from the Continental Divide near Winter Park and Fairplay (on the west edge), eastward about 107 mi (172 km); and extends from Boulder on the north edge to Woodland Park at the south edge (68 mi; 109 km).

Colorado

Digital geologic map database of the Payette National Forest and vicinity, Idaho

The geology of the Payette National Forest and vicinity, Idaho (Fig. 1), was mapped and compiled by Karen Lund between 1992 and 1996. The geologic data for the digital map are from original mapping as well as compilation by Lund of numerous sources of published and unpublished geologic maps that are cited in the section 'Bibliography of Geologic Map Sources.' The geology was compiled onto 1:100,000-scale topographic base maps for input into a geographic information system (GIS). The digital geologic map database can be queried in many ways to produce a variety of geologic maps. Digital base map data files are not included: they may be obtained from a variety of commercial and government sources. This database is not meant to be used or displayed at any scale larger than 1:100,000 (e.g., 1:62,500 or 1:24,000). This open-file report describes the geologic units and the methods used to convert the geologic map data into a digital format and documents the file structures. We wish to thank Gregory N. Green of the U.S. Geological Survey for reviewing the digital GIS files.

Idaho