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S.S. Agard

Publications and source records attributed to S.S. Agard.

6 recordsLinked to original sources
USGS1991

Quaternary history of some southern and central Rocky Mountain basins

This chapter summarizes the current state of late Cenozoic stratigraphic knowledge in some Rocky Mountain basins (here defined as the structurally low portions of major drainage basins) that have been studied in detail since Scott’s (1965) summary on the nonglacial history of the southern and middle Rocky Mountains. The Quaternary history of few of these basins has been studied as intensively as that of the surrounding mountain ranges, despite the wealth of fluvial and other types of deposits present in the basins and the potential for dating them. The areas discussed here include the Bighorn Basin in Wyoming and Montana, the Laramie Basin and part of the Sweetwater River Basin in Wyoming, the Yampa River Basin in Colorado, and the Uinta Basin in Utah (Fig. 1). Small parts of the Great Plains and Colorado Plateau physiographic provinces are included in this discussion. Correlations of deposits within and among some of the areas can now be made more confidently than in 1965 because of detailed mapping and the discovery of many more localities with dated volcanic ashes.

Colorado, Wyoming, Montana↗
USGS1984

Defining geologic Hazards for natural resources management using tree-ring analysis

Landslides, avalanches, floods, and other geologic hazards impair natural resources management by jeopardizing public safety, damaging or restricting resource utilization, and necessitating expenditures for corrective measures The negative impact of geologic hazard events can be reduced by tailoring resources management to hazard potential of an area This requires assessment of where and how frequently the events occur National forests and other managed wildlands often lack monitoring or historical records to compute frequency of hazard occurrence Tree-ring analysis, based on internal growth response to external events such as tilting and abrasion, can provide frequency data Two examples of the use of tree-ring analysis to date landslide activity illustrate advantages and limitations of the technique An example from the Fishlake National Forest in central Utah illustrates assessment for planning purposes An example from the Sierra National Forest in east-central California shows assessment applied to project design Many geologic hazards in addition to landslides are suited to tree-ring analysis to establish frequency of occurrence Hazard reduction efforts in natural resources management could be enhanced by careful application of tree-ring analysis ?? 1984 Springer-Verlag New York Inc.

Environmental Geology and Water Sciences↗