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Research about Park County, Colorado

Source-linked reports with geographic coverage including Park County, Colorado.

10 recordsLinked to original sources
USGS2023

Living with wildfire in Park County, Colorado 2021 data report

Wildfire affects many types of communities and is a particular concern for communities in the wildland urban interface (WUI), such as those of Park County, Colorado. The core intent of this project was to provide evidence to support the Platte Canyon Fire Protection District (PCFPD) and Fire Adapted Bailey in their wildfire mitigation and education programming. This report describes wildfire risk data collected in fall 2020 and pairs it with social data collected in the fall and winter of 2020-2021, in order to better understand residents’ knowledge, experiences, and perceptions about wildfire risk in the communities of the Burland Ranchettes Homeowners Association (HOA) area and surrounding neighborhoods. This greater understanding will help PCFPD focus its programs and outreach and ultimately promote increased mitigation and reduced wildfire risk in Park County.

Colorado↗
USGS2019

Geologic map of the Hartsel Quadrangle, Park County, Colorado

The Hartsel quadrangle sits nearly in the center of the complex South Park Laramide structural basin. Generally, the basin can be described as an asymmetrical down-faulted feature, dipping to the east. It is bounded by two northwest-trending uplifts: the Sawatch uplift to the west and the Front Range uplift to the east. The west-verging Elkhorn thrust, which places Proterozoic intrusive and metamorphic rocks within the Front Range uplift over Phanerozoic sediments in the basin, passes just east of the quadrangle. Seismic data and deep oil and gas well logs indicate that a series of imbricate thrust faults extend west, and in front of, the Elk horn thrust fault. The Hartsel uplift is a westward-jutting structural salient of the Front Range uplift that brings Proterozoic rocks farther into the basin south of the town of Hartsel. The quadrangle also spans the late Paleozoic boundary between the central Colorado trough (DeVoto, 1972) to the west and Frontrangia (Mallory, 1958) to the east. The Neogene Rio Grande rift system lies to the west of South Park Basin in the upper Arkansas River valley. Examples of Neogene extension can be found throughout South Park, as described by Stark and others (1949), De Voto (1971), and Ruleman and others (2011). In addition, there is evidence of ongoing local deformation related to dissolution and possible collapse of Paleozoic evaporite deposits across much of the west side of the basin (Kirkham and others, 2012).

Colorado↗
USGS2015

Monitoring-well installation, slug testing, and groundwater quality for selected sites in South Park, Park County, Colorado, 2013

During May–June, 2013, the U.S. Geological Survey, in cooperation with Park County, Colorado, drilled and installed four groundwater monitoring wells in areas identified as needing new wells to provide adequate spatial coverage for monitoring water quality in the South Park basin. Lithologic logs and well-construction reports were prepared for each well, and wells were developed after drilling to remove mud and foreign material to provide for good hydraulic connection between the well and aquifer. Slug tests were performed to estimate hydraulic-conductivity values for aquifer materials in the screened interval of each well, and groundwater samples were collected from each well for analysis of major inorganic constituents, trace metals, nutrients, dissolved organic carbon, volatile organic compounds, ethane, methane, and radon. Documentation of lithologic logs, well construction, well development, slug testing, and groundwater sampling are presented in this report.

Colorado↗
USGS2008

Ground- and surface-water chemistry of Handcart Gulch, Park County, Colorado, 2003-2006

As part of a multidisciplinary project to determine the processes that control ground-water chemistry and flow in mineralized alpine environments, ground- and surface-water samples from Handcart Gulch, Colorado were collected for analysis of inorganic solutes and water and dissolved sulfate stable isotopes in selected samples. The primary aim of this study was to document variations in ground-water chemistry in Handcart Gulch and to identify changes in water chemistry along the receiving stream of Handcart Gulch. Water analyses are reported for ground-water samples collected from 12 wells in Handcart Gulch, Colorado. Samples were collected between August 2003 and October 2005. Water analyses for surface-water samples are reported for 50 samples collected from Handcart Gulch and its inflows during a low-flow tracer injection on August 6, 2003. In addition, water analyses are reported for three other Handcart Gulch stream samples collected in September 2005 and March 2006. Reported analyses include field parameters (pH, specific conductance, temperature, dissolved oxygen, and Eh), major and trace constituents, oxygen and hydrogen isotopic composition of water and oxygen and sulfur isotopic composition of dissolved sulfate. Ground-water samples from this study are Ca-SO4 type and range in pH from 2.5 to 6.8. Most of the samples (75 percent) have pH values between 3.3 and 4.3. Surface water samples are also Ca-SO4 type and have a narrower range in pH (2.7?4.0). Ground- and surface-water samples vary from relatively dilute (specific conductance of 68 ?S/cm) to concentrated (specific conductance of 2,000 ?S/cm).

Colorado↗
USGS1995

Photogeologic map showing distribution of sinkholes south of Fairplay, Park County, Colorado — A possible geologic hazard

A large group of at least 50, and perhaps significantly more, sinkholes partially surrounds Black Mountain 6-10 mi south Fairplay in South Park, Park County, Colorado. The sinkholes occur in bedrock in the evaporite facies of the Middle Pennsylvania Minturn Formation, and in Quaternary soil, alluvium, and glacial outwash gravels that overlie the evaporite beds. Sinkholes range in size from small depressions a few feet across to large holes several hundred feet across. Measured sinkholes range in size from about 25 ft in diameter and 2 ft deep to about 235 ft in diameter and 25 ft deep. In places, several sinkholes have coalesced to form depressions as much as 750 ft long and 400 ft wide. One large cluster of small craters is about 1,8000 ft long and 600 ft wide. As reported to us by a resident rancher, one small sinkhole collapsed about 10 years ago. The area of sinkholes extends into land now under development for residences, and the sinkholes thus pose a potential hazard that needs to be considered in future development. Also, they might jeopardize existing farmland, structures, ans roads (including U.S. Highway 285), as well as projected roads and airstrips. This report is not a comprehensive evaluation of the distribution and origin of the sinkholes; its intent is to call attention to their presence and to encourage further study. Many by not all of the sinkholes were visited; the geologic map is based mainly on the interpretation of aerial photographs by D.R. Shawe.

Colorado↗
USGS1952

Results of diamond drilling and geologic investigation of the Shirley May (Garo) uranium deposit, Park County, Colorado

The Shirley May (Garo) uranium deposit near Garo, Park County, Colo., consists of tyuyamunite and carnotite that occur as disseminations and as fracture fillings in three beds of medium- to coarse-grained sandstone. The sandstones are in the Maroon formation of Permian age. This deposit was explored by means of 12 core-drill holes, totalling 2,003 feet. The deposit is on the northeast flank of the Garo anticline, a local structure that probably is related to Tertiary tectonic movement. In the vicinity of the deposit the sedimentary rocks strike northwest and dip steeply. They are cut by numerous northerly-trending faults that have horizontal displacements of as much as 1,000 feet. The ore minerals tyuyamunite, carnotite, volborthite, calciovolborthite, malachite, azurite, chalcocite(?) , and an unidentified yellow to dark-red vanadium oxide are restricted to a complexly faulted area. The ore body that has yielded most of the uranium ore is in the uppermost ore-bearing sandstone (bed no. 1) and is stratigraphically 50 and 150 feet above the ore horizons in sandstones nos. 2 and 3, respectively. The uranium content of samples from the mine workings ranges from 0. 001 to 0. 48 percent uranium; dump samples contain as much as 2.39 percent uranium. A total of 40 tons of uranium ore, averaging 1.0 percent uranium, was produced in 1919.

Colorado↗
USGS1951

Garo uranium deposits, Park County, Colorado

The uranium deposits, three-fourths of a mile south of Garo, Park County, Colo., were mined over 30 years ago for radium ore. The old workings are now abandoned and inaccessible. Forty tons of ore that contained 1.0 percent uranium are reported to have been mined from two light-gray sandstone beds that are stratigraphically about 100 feet apart. The minerals reported to occur in these sandstones are carnotite, malachite, azurite, calciovolborthite, and volborthite. The deposits are in close proximity to a radioactive cherty limestone which is one foot thick, that contains as much as 0.01 percent uranium. The uranium in the carnotite and the uranium in the chert may be genetically related. Mr. ¥. H. Gaddis of Hartsel, Colo., has recently attempted to reopen some of the workings, but as of April 1951 this operation had not revealed any significant new data. Future prospecting should be initiated in the two sandstone beds that have been mineralized. The chert can be used as a marker bed in correlating the sandstones from one exposure to another.

Colorado↗