Locations and areas of Colorado cities, towns, municipal perimeters, and FIPS codes from the Colorado Department of Transportation (CDOT).

This map layer represents point locations of cities and towns from the Geographic Names Information System (GNIS).

This web map created by the Colorado Governor's Office of Information Technology GIS team, serves as a basemap specific to the state of Colorado. The basemap includes general layers such as counties, municipalities, roads, waterbodies, state parks, national forests, national wilderness areas, and trails.Layers:Layer descriptions and sources can be found below. Layers have been modified to only represent features within Colorado and are not up to date. Layers last updated February 23, 2023. Colorado State Extent: Description: “This layer provides generalized boundaries for the 50 States and the District of Columbia.” Notes: This layer was filtered to only include the State of ColoradoSource: Esri Living Atlas USA States Generalized Boundaries Feature LayerState Wildlife Areas:Description: “This data was created by the CPW GIS Unit. Property boundaries are created by dissolving CDOWParcels by the property name, and property type and appending State Park boundaries designated as having public access. All parcel data correspond to legal transactions made by the CPW Real Estate Unit. The boundaries of the CDOW Parcels were digitized using metes and bounds, BLM's GCDB dataset, the PLSS dataset (where the GCDB dataset was unavailable) and using existing digital data on the boundaries.” Notes: The state wildlife areas layer in this basemap is filtered from the CPW Managed Properties (public access only) layer from this feature layer hosted in ArcGIS Online Source: Colorado Parks and Wildlife CPW Admin Data Feature LayerMunicipal Boundaries:Description: "Boundaries data from the State Demography Office of Colorado Municipalities provided by the Department of Local Affairs (DOLA)"Source: Colorado Information Marketplace Municipal Boundaries in ColoradoCounties:Description: “This layer presents the USA 2020 Census County (or County Equivalent) boundaries of the United States in the 50 states and the District of Columbia. It is updated annually as County (or County Equivalent) boundaries change. The geography is sources from US Census Bureau 2020 TIGER FGDB (National Sub-State) and edited using TIGER Hydrology to add a detailed coastline for cartographic purposes. Geography last updated May 2022.” Notes: This layer was filtered to only include counties in the State of ColoradoSource: Esri USA Census Counties Feature LayerInterstates:Description: Authoritative data from the Colorado Department of Transportation representing Highways Notes: Interstates are filtered by route sign from this CDOT Highways layer Source: Colorado Department of Transportation Highways REST EndpointU.S. Highways:Description: Authoritative data from the Colorado Department of Transportation representing Highways Notes: U.S. Highways are filtered by route sign from this CDOT Highways layer Source: Colorado Department of Transportation Highways REST EndpointState Highways:Description: Authoritative data from the Colorado Department of Transportation representing Highways Notes: State Highways are filtered by route sign from this CDOT Highways layer Source: Colorado Department of Transportation Highways REST EndpointMajor Roads:Description: Authoritative data from the Colorado Department of Transportation representing major roads Source: Colorado Department of Transportation Major Roads REST EndpointLocal Roads:Description: Authoritative data from the Colorado Department of Transportation representing local roads Source: Colorado Department of Transportation Local Roads REST EndpointRail Lines:Description: Authoritative data from the Colorado Department of Transportation representing rail lines Source: Colorado Department of Transportation Rail Lines REST EndpointCOTREX Trails:Description: “The Colorado Trail System, now titled the Colorado Trail Explorer (COTREX), endeavors to map every trail in the state of Colorado. Currently their are nearly 40,000 miles of trails mapped. Trails come from a variety of sources (USFS, BLM, local parks & recreation departments, local governments). Responsibility for accuracy of the data rests with the source.These data were last updated on 2/5/2019” Source: Colorado Parks and Wildlife CPW Admin Data Feature LayerNHD Waterbodies:Description: “The National Hydrography Dataset Plus (NHDplus) maps the lakes, ponds, streams, rivers and other surface waters of the United States. Created by the US EPA Office of Water and the US Geological Survey, the NHDPlus provides mean annual and monthly flow estimates for rivers and streams. Additional attributes provide connections between features facilitating complicated analyses.”Notes: This layer was filtered to only include waterbodies in the State of ColoradoSource: National Hydrography Dataset Plus Version 2.1 Feature LayerNHD Flowlines:Description: “The National Hydrography Dataset Plus (NHDplus) maps the lakes, ponds, streams, rivers and other surface waters of the United States. Created by the US EPA Office of Water and the US Geological Survey, the NHDPlus provides mean annual and monthly flow estimates for rivers and streams. Additional attributes provide connections between features facilitating complicated analyses.”Notes: This layer was filtered to only include flowline features in the State of ColoradoSource: National Hydrography Dataset Plus Version 2.1 Feature LayerState Parks:Description: “This data was created by the CPW GIS Unit. Property boundaries are created by dissolving CDOWParcels by the property name, and property type and appending State Park boundaries designated as having public access. All parcel data correspond to legal transactions made by the CPW Real Estate Unit. The boundaries of the CDOW Parcels were digitized using metes and bounds, BLM's GCDB dataset, the PLSS dataset (where the GCDB dataset was unavailable) and using existing digital data on the boundaries.” Notes: The state parks layer in this basemap is filtered from the CPW Managed Properties (public access only) layer from this feature layer Source: Colorado Parks and Wildlife CPW Admin Data Feature LayerDenver Parks:Description: "This dataset should be used as a reference to locate parks, golf courses, and recreation centers managed by the Department of Parks and Recreation in the City and County of Denver. Data is based on parcel ownership and does not include other areas maintained by the department such as medians and parkways. The data should be used for planning and design purposes and cartographic purposes only."Source: City and County of Denver Parks REST EndpointNational Wilderness Areas:Description: “A parcel of Forest Service land congressionally designated as wilderness such as National Wilderness Area.”Notes: This layer was filtered to only include National Wilderness Areas in the State of ColoradoSource: United States Department of Agriculture National Wilderness Areas REST EndpointNational Forests: Description: “A depiction of the boundaries encompassing the National Forest System (NFS) lands within the original proclaimed National Forests, along with subsequent Executive Orders, Proclamations, Public Laws, Public Land Orders, Secretary of Agriculture Orders, and Secretary of Interior Orders creating modifications thereto, along with lands added to the NFS which have taken on the status of 'reserved from the public domain' under the General Exchange Act. The following area types are included: National Forest, Experimental Area, Experimental Forest, Experimental Range, Land Utilization Project, National Grassland, Purchase Unit, and Special Management Area.”Notes: This layer was filtered to only include National Forests in the State of ColoradoSource: United States Department of Agriculture Original Proclaimed National Forests REST Endpoint

Created and managed by the Department of Local Affairs (DOLA) at the State of Colorado, this data shows all the local municipalities within the state. Attribution includes information regarding the municipality name, description, order number, etc.For more information on municipalities in the State of Colorado, visit the DOLA website here.

Census ZIP Code Tabulation Areas This feature layer, utilizing National Geospatial Data Asset (NGDA) data from the U.S. Census Bureau (USCB), displays ZIP Code Tabulation Areas in the United States. Per the USCB, “ZIP Code Tabulation Areas (ZCTAs) are approximate area representations of U.S. Postal Service (USPS) ZIP Code service areas that the Census Bureau creates to present statistical data for each decennial census. Data users should not use ZCTAs to identify the official USPS ZIP Code for mail delivery. The USPS makes periodic changes to ZIP Codes to support more efficient mail delivery.” Tabulation Area: 90210 Data currency: This cached Esri federal service is checked weekly for updates from its enterprise federal source (ZIP Code Tabulation Areas) and will support mapping, analysis, data exports and OGC API – Feature access.NGDAID: 58 (Series Information for 2020 Census 5-Digit ZIP Code Tabulation Area (ZCTA5) National TIGER/Line Shapefiles, Current)OGC API Features Link: (Census ZIP Code Tabulation Areas - OGC Features) copy this link to embed it in OGC Compliant viewersFor more information, please visit: ZIP Code Tabulation Areas (ZCTAs)For feedback please contact: Esri_US_Federal_Data@esri.comThumbnail source: Esri BasemapsNGDA Data Set This data set is part of the NGDA Governmental Units, and Administrative and Statistical Boundaries Theme Community. Per the Federal Geospatial Data Committee (FGDC), this theme is defined as the “boundaries that delineate geographic areas for uses such as governance and the general provision of services (e.g., states, American Indian reservations, counties, cities, towns, etc.), administration and/or for a specific purpose (e.g., congressional districts, school districts, fire districts, Alaska Native Regional Corporations, etc.), and/or provision of statistical data (census tracts, census blocks, metropolitan and micropolitan statistical areas, etc.). Boundaries for these various types of geographic areas are either defined through a documented legal description or through criteria and guidelines. Other boundaries may include international limits, those of federal land ownership, the extent of administrative regions for various federal agencies, as well as the jurisdictional offshore limits of U.S. sovereignty. Boundaries associated solely with natural resources and/or cultural entities are excluded from this theme and are included in the appropriate subject themes.” For other NGDA Content: Esri Federal Datasets

These data provide an accurate high-resolution shoreline compiled from imagery of COLORADO RIVER TO BAY CITY, TX . This vector shoreline data is based on an office interpretation of imagery that may be suitable as a geographic information system (GIS) data layer. This metadata describes information for both the line and point shapefiles. The NGS attribution scheme 'Coastal Cartographic Object...

Vector polygon map data of property parcels from Denver, Colorado containing 231,961 features.

Property parcel GIS map data consists of detailed information about individual land parcels, including their boundaries, ownership details, and geographic coordinates.

Property parcel data can be used to analyze and visualize land-related information for purposes such as real estate assessment, urban planning, or environmental management.

Available for viewing and sharing as a map in a Koordinates map viewer. This data is also available for export to DWG for CAD, PDF, KML, CSV, and GIS data formats, including Shapefile, MapInfo, and Geodatabase.

A layer depicting cities boundaries in Adams County, Colorado. The city boundaries are derived from the Zoning layer. Updated Monthly.

Urban Trees in the City of Boulder, Colorado Tree Inventory. Most of the trees are managed by the Urban Forestry Division within the Department of Parks and Recreation. A data dictionary with descriptions of the fields included in the dataset can be downloaded here. This document contains field names and aliases, detailed descriptions of fields, a list of values and units for each field, and previous field names where relevant. This document should be used in conjunction with the Public Trees open dataset.

The City of Fort Collins GIS Online Mapping tool (FCMaps) provide current, timely and local geographic information in an easy to use viewer. FCMaps is mobile friendly and will work well on tablets and smartphones as well as a desktop browser.

Here you will find locations of ground control points in NAD83 stateplane coordinates.

This Unoccupied Aerial Vehicle (UAV) survey was flown to provide geology field camp students with a high-resolution orthomosaic, Digital Elevation Model (DEM), and Point Cloud of the entrance to the Grape Creek mapping area. The area shows monocline of Cretaceous beds dipping to the Southeast in the Frontal Range.

Detailed road map of Weld County. The map includes roads, city limits, water features, and state/federal lands. This is a PDF map that is regularly updated.Tables included on the map are also available as stand-alone PDFs. See the County Road Cross Reference and Road/Street Cross Reference tables. Accessibility and ADA Information

The City of Fort Collins GIS Online Mapping tool (FCMaps) provide current, timely and local geographic information in an easy to use viewer. FCMaps is mobile friendly and will work well on tablets and smartphones as well as a desktop browser.

Here you will find locations of Transfort bus stops, including those that are ADA compliant.

The dataset was generated to describe historical land-use and land-cover (LULC)for the northern Colorado urban Front Range (which includes the cities of Boulder, Fort Collins, Greeley, and Denver) for an area covering approximately 1,023,660 hectares. The Front Range urban landscape is diverse and interspersed with highly productive agriculture as well as natural land cover types including evergreen forest in the Rocky Mountain foothills and Great Plains grassland. To understand the dynamics of urban growth, raster maps were created at a 1-meter resolution for each of four time steps, nominally 1937, 1957, 1977, and 1997. In total, 8 to 38 LULC classes were identified using manual interpretation techniques, aerial photographs, historical maps, and other available information. The maps provide high resolution spatial data for understanding the historical progression of urbanization and will allow further analysis of the effects of urban growth on social and ecological systems.

Neighborhoods of the City of Aurora, Colorado. The City of Aurora, Colorado sits in three different counties: Adams County, Arapahoe County, and Douglas County and lies just east of the City and County of Denver. The city's population was estimated at 381,000 on July 1, 2019.

A digital raster graphic (DRG) is a scanned image of a U.S.Geological Survey (USGS) topographic map. The scanned image includes all map collar information. The image inside the map neatline is georeferenced to the surface of Earth. The DRG can be used to collect, review, and revise other digital data especially digital line graphs (DLG). When the DRG is combined with other digital products, such as digital orthophoto quadrangles (DOQ) or digital elevation models (DEM), the resulting image provides additional visual information for the extraction and revision of base cartographic information. The USGS is producing DRGs of the 1:24,000-, 1:25,000-, 1:63,360-(Alaska), 1:100,000-, and 1:250,000-scale topographic map series. NOTE: This EML metadata file does not contain important geospatial data processing information. Before using any NWT LTER geospatial data read the arcgis metadata XML file in either ISO or FGDC compliant format, using ArcGIS software (ArcCatalog > description), or by viewing the .xml file provided with the geospatial dataset.

City boundary for Longmont Colorado

Background Despite the infrequency of storms, the City of Colorado Springs Streets Division must be prepared for minor and major snowstorms from September through May. The City's Streets Division is responsible for approximately 6,480 lane miles of roadway, extending over a 202 square mile area. While average annual snowfall stands at 42 inches, snow can pile up quickly, at varying rates throughout the City. Elevation and wind can compound accumulation, causing an immediate impact on the City's mobility. Hence, the need for safe and passable streets is a priority for the Streets Division.Route TypePrimary Routes, which are multi-lane roads with large volumes of traffic or hospital access, are treated first. Once the primary routes are passable, snow crews move on to Secondary Routes, which includes school access and collector streets that serve as the main connections between neighborhoods and primary roads. If there is continuous snowfall, the Primary Routes may have to be plowed more than once, which will delay the response on secondary streets.Street Treatments The City uses three materials on City streets. The first material is called "anti-skid" and is used on most snow routes. Anti-skid can contain up to 20 percent salt, and is used to aid in vehicle traction. The second material is used on many of the City's thoroughfares and is called "IceSlicer." This material is a de-icer and will lower the freezing temperature of water. IceSlicer will work down to around 10 degrees. The third material is “APEX” and is a liquid. It is applied to the roadway before a storm or right as snow begins to fall. It is intended to help stop the bond of snow/ice to the roadway and aids in clean-up after the storms conclusion.For more information about the City of Colorado Springs Street Division, please click hereState and County Roads All State and County roads are maintained by their own staff. For information on snow removal on State or County roads, call: CDOT winter road conditions, (303) 639-1111 CDOT road maintenance office (Colorado Springs), (719) 634-2323 or (719) 576-1868 El Paso County Department of Transportation office, (719) 520-6460 Contact information City of Colorado Springs Streets Division, (719) 385-5934 24-Hour Answering Service, (719) 278-8352 Streets Division automated snow hotline, (719) 385-SNOW National Weather Service Forecast information for Colorado Springs, (303) 573-6846 What to Know for Snow City information - WinterStormsFor more information please check out the Snow Plow Information site HERE

ArcGIS 3D scene layer created from the city of Boulder's 2013 LiDAR multipatch building data. For 3D buildings outside the city of Boulder, please see OpenStreetMap 3D Buildings.

This data release includes Al-26/Be-10 cosmogenic nuclide concentrations and burial isochron ages for three locations in central Colorado, USA, with preferred burial ages ranging from ~2 Ma to 600 ka, that provide constraints on geologic mapping and chronostratigraphic correlations of Pleistocene Colorado Rocky Mountain (CRM)-Great Plains deposits. This new dataset helps to validate original identification and characterization of the deposits by renowned work of early to late 20th century geologists. In addition, this dataset is critical for any models of geomorphic development of modern Colorado Rocky Mountain (CRM)-Great Plains depositional systems, including analyses of regional relationships involving the Malta Gravel, Nussbaum Alluvium, Rocky Flats Alluvium, Verdos Alluvium, and Slocum Alluvium (Scott, 1960; Tweto, 1961; Epis and others, 1976, 1980). Paired with cosmogenic analyses for the Nussbaum Alluvium at Baculite Mesa (1.30 ± 0.08 Ma) (Odom and others, 2024) and a glacial advance of the Laurentide icesheet of Balco and Rovey (2010) at 1.31 ± 0.13 Ma, this dataset provides the chronologic constraints for onset of Pleistocene Rocky Mountain river incision and Great Plains river entrenchment for the South Platte and Arkansas Rivers, and the establishment of the current river positions. Three classic localities of previously mapped and described deposits were sampled in the field for cosmogenic nuclide analysis. A summary of the characteristics of these sites is as follows: (1) The Central City gravel is a 160 meter-thick (525 feet), matrix-supported, pebble to boulder gravel with a silty sand matrix, nonstratified to crude stratification, and no distinct clast imbrication (Kellogg and others, 2008) lying within the CRM Front Range foothills along Clear Creek at an elevation of approximately 2,430 m/7,960 ft asl. It was originally identified as the first Pleistocene glacial deposit emanating from ice caps developed on the Continental Divide across the CRM Front Range (Spurr and others, 1908; Atwood and Atwood, 1938). More recent work has placed this deposit as a Neogene/Miocene gravel associated with the Ogalalla Formation on the Great Plains (Kellogg and others, 2008), and disregarded its glacial origin and designation as till by the initial investigators. Seven samples of cobbles and clayey, silty sand matrix were measured for an Al-26/Be-10 burial isochron. Two samples, 17-CO-047-CEN and 18-CO-002-CEN, featured depressed Al-26/Be-10 ratios indicative of prior burial and were excluded from further calculations. The final burial isochron for this site yielded a burial age of 1.44 ± 0.26 Ma (1σ analytical uncertainty). (2) The Pliocene-early Pleistocene, Malta Gravel (Tweto, 1961; McCalpin and others, 2012; Ruleman and others, 2018) is a reddish-brown to yellow-red, angular to subangular, pebble to cobble gravel with a silty sand matrix exposed in a railroad cut ~5 km/3.1 mi west of Leadville, Colorado at the headwaters of the Arkansas River (McCalpin and others, 2012). It was originally defined as an early-middle Pleistocene glaciofluvial deposit (Tweto, 1961), but was more recently identified as non-glacial in origin and possibly within the uppermost section of the Neogene Dry Union Formation (McCalpin and others, 2012; Kellogg and others, 2017). Twelve samples of sand and cobbles were collected for analyses approximately 5 meters (16.4 feet) below the deposit surface and below a heavily oxidized pedogenic horizon overlain by pre-Bull Lake glaciofluvial deposits of early or middle Pleistocene age. One sample, 17-CO-039-LV-Ac, featured a depressed Al-26/Be-10 ratio and was excluded from further calculations. The final burial isochron for this site yielded a burial age of 1.97 ± 0.04 Ma (1σ analytical uncertainty). (3) Lava Creek B ash location in the central upper Arkansas River valley, north of Buena Vista, CO is a heavily oxidized, fluvially reworked tephra within a faulted and fractured outcrop of clayey, silty sand deposits, overlain by pre-Bull Lake glacial deposits of middle Pleistocene age (Scott, 1975; Kellogg and others, 2017). The ash lies within the uppermost Dry Union Formation (Kellogg and others, 2013). Probable seismogenic sand dikes are pervasive throughout the exposure. Twelve samples for analyses were collected approximately 9 meters (29.5 feet) below the surface and 40 centimeters (15.8 inches below the basal Lava Creek B ash layer within a silty sand and pebble gravel. One sample, 17-CO-032-BV-A, featured a depressed Al-26/Be-10 ratio indicative of prior burial and was excluded from further calculations. All other samples had nearly identical mean Be-10 concentrations clustering between 601,000-651,000 atoms/gram (at/g) and Al-26 concentrations clustering between 2,913,000-3,429,000 at/g. These overlapping concentrations precluded a burial isochron calculation and necessitated minimum/maximum burial dating. The mean minimum burial age was ~570 ka and mean maximum burial age was ~690 ka, overlapping with the preferred sanidine 40Ar/39Ar isochron date of 631.3 ± 4.3 ka for the Lava Creek B ash (Matthews and others, 2015). These new ages provide a middle Pleistocene age for the minimum age of the Dry Union Formation, and chronostratigraphic correlation to the uppermost Dry Union Formation with the uppermost Santa Fe Group within the San Luis Valley (Ruleman and others, 2021). References: Atwood, W.W., and Atwood, W.W., 1938, Opening of the Pleistocene in the Rocky Mountains of the United States, The Journal of Geology, v. 46, no. 3, p. 239–247, https://www.jstor.org/stable/30081297 Balco, Greg, and Rovey, C.W., 2010, Absolute chronology for major Pleistocene advances of the Laurentide Ice Sheet, Geology, v. 38, no. 9, p. 795–798, doi: https://doi.org/10.1130/G30946.1 Epis, R.C., Scott, G.R., Taylor, R.B., and Chapin, C.E. 1976, Cenozoic volcanic, tectonic, and geomorphic features of central Colorado, Professional Contributions of the Colorado School of Mines No. 8, p. 323-338. Epis, R.C., Scott, G.R., Taylor, R.B., and Chapin, C.E., 1980, Summary of Cenozoic geomorphic, volcanic, and tectonic features of central Colorado and adjoining areas, in Kent, H.C., Porter, K.W., eds., Colorado Geology: Denver Colo., Rocky Mountain Association of Geologists, p. 135-156. Kellogg, K.S., Shroba, R.R., Bryant, Bruce, and Premo, W.R., 2008, Geologic map of the Denver West 30’ x 60’ quadrangle, north-central Colorado: U.S. Geological Survey Scientific Investigations Map 3000, scale 1:100,000, 48-p. pamphlet.Kellogg, K.S., Lee, Keenan, Premo, W.R., and Cosca, M.A., 2013, Geologic map of the Harvard Lakes 7.5' quadrangle, Park and Chaffee Counties, Colorado: U.S. Geological Survey Scientific Investigations Map 3267, 22 p., scale 1;24,000, https://dx.doi.org/10.3133/sim3267. Kellogg, K.S., Lee, Keenan, Premo, W.R., and Cosca, M.A., 2013, Geologic map of the Harvard Lakes 7.5' quadrangle, Park and Chaffee Counties, Colorado: U.S. Geological Survey Scientific Investigations Map 3267, 22 p., scale 1;24,000, https://dx.doi.org/10.3133/sim3267. Kellogg, K.S., Shroba, R.R., Ruleman, C.A., Bohannon, R.G., McIntosh, W. C., Premo, W.R., Cosca, M.A., Moscati, R.J., and Brandt, T.R., 2017, Geologic map of the upper Arkansas River valley region, north-central Colorado: U.S. Geological Survey Scientific Investigations Map 3382, pamphlet 70 p., 2 sheets, scale 1:50,000, https://doi.org/10.3133/sim3382. Matthews, N.E., Vazquez, J.A., and Calvert, A.T., 2015, Age of the Lava Creek supereruption and magma chamber assembly at Yellowstone based on 40Ar/39Ar and U-Pb dating of sanidine and zircon crystals, Geochemistry, Geophysics, and Geosystems, v. 16, no. 8, p. 2508-2528, https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015GC005881. McCalpin, J.P., Funk, Jonathan, and Mendel, David, 2012, Leadville South Quadrangle Geologic Map, Lake County, Colorado, Colorado Geological Survey Open-File Report 12-06, 54 p., 2 plates, 1:24,000 scale. Odom, W.E., Ruleman, C.A., Sterne, E.J., O'Keeffe, M.K., and Morgan, M.L., 2024, Cosmogenic Al-26/Be-10 Isochron Burial Data for the Nussbaum Gravel at Baculite Mesa, CO: U.S. Geological Survey data release, https://doi.org/10.5066/P1B2MCHG. Ruleman, C.A., Brandt, T.R., Caffee, M.W., and Goehring, B.M., 2018, Geologic map of the Leadville North 7.5’ quadrangle, Eagle and Lake Counties, Colorado: U.S. Geological Survey Scientific Investigations Map 3400, 1:24,000, https://doi.org/10.3133/sim3400. Ruleman, C.A., and Brandt, T.R., 2021, Surficial geology of the northern San Luis Valley, Saguache, Fremont, Custer, Alamosa, Rio Grande, Conejos, and Costilla Counties, Colorado: U.S. Geological Survey Scientific Investigations Map 3475, 2 sheets, scale 1:75,000, https://doi.org/10.3133/sim3475. Scott, G.R., 1960, Subdivision of the Quaternary Alluvium East of the Front Range Near Denver, Colorado, Bulletin of the Geological Society of America, v. 71, p. 1541-1544. Scott, G.R., 1975, Reconnaissance geologic map of the Buena Vista quadrangle, Chaffee and Park Counties, Colorado, U.S. Geological Survey Miscellaneous Field Studies Map MF-657, 1:62,500 scale. Spurr, J.E., Garrey, G.H., and Ball, S.H., 1908, Economic Geology of the Georgetown Quadrangle, Together with the Empire District, U.S. Geological Survey Professional Paper 63, 507 p., 4 plates. Tweto, Ogden, 1961, Late Cenozoic events of the Leadville district and upper Arkansas Valley, Colorado, Geological Survey Research 1961, short papers in the geologic and hydrologic sciences Articles 1-146, U.S. Geological Survey Professional Paper, 424-B, p. B133-B135.