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Juli Fahy

Publications and source records attributed to Juli Fahy.

2 recordsLinked to original sources

Rainfall-Runoff and Erosion Data from the Mancos Shale Formation in the Gunnison Gorge National Conservation Area, Southwestern Colorado, 2003-2006

Data were collected and experiments were conducted from 2003 to 2006 by the U.S. Geological Survey, in cooperation with the Bureau of Land Management, to support research into understanding processes that liberate, disperse, and concentrate erosion byproducts in Mancos Shale landscapes. The study area was the Gunnison Gorge National Conservation Area near Montrose and Delta, Colorado. This report includes data collected from 24, small-plot, rainfall-runoff simulations, 6 hillslope-erosion monitoring plots, 20 hillslope-creep monitoring sites, and 3 precipitation gages. Small-plot rainfall-runoff simulations were performed on paired (undisturbed and disturbed) plots to examine the effect of off-highway vehicle use on runoff and erosion. These data were collected in conjunction with several other studies done by the U.S. Geological Survey in the Gunnison Gorge National Conservation Area. Data collected in companion studies are published in separate open-file reports.

Open-File Report

Results of chemical analyses of soil, shale, and soil/shale extract from the Mancos Shale formation in the Gunnison Gorge National Conservation Area, southwestern Colorado, and at Hanksville, Utah

Results of chemical and some isotopic analyses of soil, shale, and water extracts collected from the surface, trenches, and pits in the Mancos Shale are presented in this report. Most data are for sites on the Gunnison Gorge National Conservation Area (GGNCA) in southwestern Colorado. For comparison, data from a few sites from the Mancos landscape near Hanksville, Utah, are included. Twelve trenches were dug on the GGNCA from which 258 samples for whole-rock (total) analyses and 187 samples for saturation paste extracts were collected. Sixteen of the extract samples were duplicated and subjected to a 1:5 water extraction for comparison. A regional soil survey across the Mancos landscape on the GGNCA generated 253 samples for whole-rock analyses and saturation paste extractions. Seventeen gypsum samples were collected on the GGNCA for sulfur and oxygen isotopic analysis. Sixteen samples were collected from shallow pits in the Mancos Shale near Hanksville, Utah.

Colorado, Utah