Statistical Analysis of Geochemical Data from Glacier Bay National Monument, Alaska
Johnson BR. 1978. Statistical Analysis of Geochemical Data from Glacier Bay National Monument, Alaska. U.S. Geological Survey (USGS) Open-File Report. USGS Open-File Report: 78-495. United States Geological Survey. Reston, VA
The U.S. Geological Survey collected both bedrock and stream-sediment samples in Glacier Bay National Monument during the 1966, 1975, 1976, and 1977 field seasons. The 1975 through 1977 samples were collected as part of a joint Geological Survey - U.S. Bureau of Mines mineral-resource appraisal (Brew and others, 1978). Some stream-sediment samples collected in 1966, as part of an earlier Survey project (MacKevett and others, 1971), were reanalyzed with the later samples and are included in the data set. Johnson and others (1978) found that analytical variation was a large portion of the total variation in a geochemical sampling program of a similar area to the southeast. For this reason, duplicate samples were collected at all stream-sediment sites in Glacier Bay beginning in 1975. Analytical values were averaged for each site prior to statistical analysis Therefore, stream-sediment locations illustrated in this report represent site means, although sites collected in 1966 are based on single samples. At least one bedrock sample was collected for geochemical analysis at each geologic station. Approximately one station per square kilometer of outcrop was collected in the western third of the monument. Bedrock sample density thins rapidly to the east, averaging approximately one station per fifty square kilometers along the eastern boundary. Each distinct lithology at a site was sampled and particular care was taken to sample all rocks with visible alteration, staining, or ore minerals. For this reason, the total bedrock sample population is considered somewhat biased toward samples high in metals of economic interest. Since multiple rock samples at one site may represent differing lithologies, site means were not generated for bedrock samples.
- Type
- Published Report
- Authors
- Johnson, B.
- Date of Issue
- 1978
- Publisher
- United States Geological Survey
- Units
- GLBA , HIST
- Keywords
- AK, Alaska, Analysis, Data, ehistory, geochem. maps, Geochemistry, Geology, Glacier Bay National Park, Glacier Bay National Park and Preserve, GLBA, History, Map, Monographic, Report, Serial, Southeastern Alaska, Statistical Analysis, Statistics, Surveys, United States, USGS, Western U.S.