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 polygonal representation of the Assessment Map Index for the City and County of Denver.

Disclaimer

ACCESS CONSTRAINTS:

None.

USE CONSTRAINTS:

The City and County of Denver is not responsible and shall not be liable to the user for damages of any kind arising out of the use of data or information provided by the City and County of Denver, including the installation of the data or information, its use, or the results obtained from its use.

ANY DATA OR INFORMATION PROVIDED BY THE City and County of Denver IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Data or information provided by the City and County of Denver shall be used and relied upon only at the user's sole risk, and the user agrees to indemnify and hold harmless the City and County of Denver, its officials, officers and employees from any liability arising out of the use of the data/information provided.

NOT FOR ENGINEERING PURPOSES

Infrastructure, such as roads, airports, water and energy transmission and distribution facilities, sewage treatment plants, and many other facilities, is vital to the sustainability and vitality of any populated area. Rehabilitation of existing and development of new infrastructure requires three natural resources: natural aggregate (stone, sand, and gravel), water, and energy http://rockyweb.cr.usgs.gov/frontrange/overview.htm.

The principal goals of the U.S. Geological Survey (USGS) Front Range Infrastructure Resources Project (FRIRP) were to develop information, define tools, and demonstrate ways to: (1) implement a multidisciplinary evaluation of the distribution and quality of a region's infrastructure resources, (2) identify issues that may affect availability of resources, and (3) work with cooperators to provide decision makers with tools to evaluate alternatives to enhance decision-making. Geographic integration of data (geospatial databases) can provide an interactive tool to facilitate decision-making by stakeholders http://rockyweb.cr.usgs.gov/frontrange/overview.htm.

This is a comment on the preliminary Congressional Commission redistricting map. Along with providing feedback on that map, it offers a draft alternative that better meets the criteria of the Colorado Constitution. As background, I participated in redistricting initiatives in South Bend, Indiana, in the mid-1980s and for Indiana legislative seats after the 1990 census. I didn’t engage with redistricting during the rest of my 20-year military career. After retiring, and while serving as Public Trustee for El Paso County, I participated in redistricting efforts at the county and city level. I also stood for El Paso County Clerk in 2010. I have lived in Colorado since 2000. The draft alternative map is created using Dave’s Redistricting App (DRA) and can be found at https://davesredistricting.org/join/346f297c-71d1-4443-9110-b92e3362b105. I used DRA because it was more user-friendly in that it allows selection by precinct and by city or town, while the tool provided by the commission seems to allow only selection by census block (or larger clusters). The two tools also use slightly different population estimates, but this will be resolved when the 2020 data are released in August. These comments acknowledge that any map created using estimated populations will need to change to account for the actual census data.

Description of Draft Alternative

    My process started by

identifying large-scale geographic communities of interest within Colorado: the Western Slope/mountain areas, the Eastern Plains, Colorado Springs/El Paso County, the North Front Range, and Denver Metro. Two smaller geographic communities of interest are Pueblo and the San Luis Valley—neither is nearly large enough to sustain a district and both are somewhat distinct from their neighboring communities of interest. A choice thus must be made about which other communities of interest to group them with. El Paso County is within 0.3% of the optimal population, so it is set as District 5. The true Western Slope is not large enough to sustain a district, even with the obvious addition of Jackson County. Rather than including the San Luis Valley with the Western Slope, the preliminary commission map extends the Western Slope district to include all of Fremont County (even Canon City, Florence, and Penrose), Clear Creek County, and some of northern Boulder County. The draft alternative District 3 instead adds the San Luis Valley, the Upper Arkansas Valley (Lake and Chaffee Counties, and the western part of Fremont County), Park and Teller Counties, and Custer County. The draft alternative District 4 is based on the Eastern Plains. In the south, this includes the rest of Fremont County (including Canon City), Pueblo, and the Lower Arkansas Valley. In the north, this includes all of Weld County, retaining it as an intact political subdivision. This is nearly enough population to form a complete district; it is rounded out by including the easternmost portions of Adams and Arapahoe Counties. All of Elbert County is in this district; none of Douglas County is. The draft alternative District 2 is placed in the North Front Range and includes Larimer, Boulder, Gilpin, and Clear Creek Counties. This is nearly enough population to form a complete district, so it is rounded out by adding Evergreen and the rest of Coal Creek in Jefferson County. The City and County of Denver (and the Arapahoe County enclave municipalities of Glendale and Holly Hills) forms the basis of draft alternative District 1. This is a bit too large to form a district, so small areas are shaved off into neighboring districts: DIA (mostly for compactness), Indian Creek, and part of Marston. This leaves three districts to place in suburban Denver. The draft alternative keeps Douglas County intact, as well as the city of Aurora, except for the part that extends into Douglas County. The map prioritizes the county over the city as a political subdivision. Draft alternative District 6, anchored in Douglas County, extends north into Arapahoe County to include suburbs like Centennial, Littleton, Englewood, Greenwood Village, and Cherry Hills Village. This is not enough population, so the district extends west into southern Jefferson County to include Columbine, Ken Caryl, and Dakota Ridge. The northwestern edge of this district would run along Deer Creek Road, Pleasant Park Road, and Kennedy Gulch Road. Draft alternative District 8, anchored in Aurora, includes the rest of western Arapahoe County and extends north into Adams County to include Commerce City, Brighton (except the part in Weld County), Thornton, and North Washington. In the draft alternative, this district includes a sliver of Northglenn east of Stonehocker Park. While this likely would be resolved when final population totals are released, this division of Northglenn is the most notable division of a city within a single county other than the required division of Denver. Draft alternative District 7 encompasses what is left: The City and County of Broomfield; Westminster, in both Jefferson and Adams Counties; Federal Heights, Sherrelwood, Welby, Twin Lakes, Berkley, and almost all of Northglenn in western Adams County; and Lakewood, Arvada, Golden, Wheat Ridge, Morrison, Indian Hills, Aspen Park, Genesee, and Kittredge in northern Jefferson County. The border with District 2 through the communities in the western portion of Jefferson County would likely be adjusted after final population totals are released.

Comparison of Maps

Precise Population Equality
    The preliminary commission

map has exact population equality. The draft alternative map has a variation of 0.6% (4,239 persons). Given that the maps are based on population estimates, and that I left it at the precinct and municipality level, this aspect of the preliminary map is premature to pinpoint. Once final population data are released, either map would need to be adjusted. It would be simple to tweak district boundaries to achieve any desired level of equality. That said, such precision is a bit of a fallacy: errors in the census data likely exceed the 0.6% in the draft map, the census data will be a year out of date when received, and relative district populations will fluctuate over the next 10 years. Both the “good-faith effort†and “as practicable†language leave room for a bit of variance in service of other goals. The need to “justify any variance†does not mean “no variance will be allowed.†For example, it may be better to maintain unity in a community of interest or political subdivision rather than separate part of it for additional precision. The major sticking point here is likely to be El Paso County: given how close it seems to be to the optimal district size, will it be worth it to divide the county or one of its neighbors to achieve precision? The same question would be likely to apply among the municipalities in Metro Denver.

Contiguity
    The draft alternative map

meets this requirement. The preliminary commission map violates the spirit if not the actual language of this requirement. While its districts are connected by land, the only way to travel to all parts of preliminary Districts 3 and 4 without leaving the districts would be on foot. There is no road connection between the parts of Boulder County that are in District 3 and the rest of that district in Grand County without leaving the district and passing through District 2 in either Gilpin or Larimer Counties. There also is no road connection between some of the southwestern portions of Mineral County and the rest of District 4 without passing through Archuleta or Hinsdale Counties in District 3.

Voting Rights Act
    The preliminary staff

analysis assumes it would be possible to create a majority-minority district; they are correct, it can be done via a noncompact district running from the west side of Denver up to Commerce City and Brighton and down to parts of northeastern Denver and northern Aurora. Such a district would go against criteria for compactness, political subdivisions, and even other definitions of communities of interest. Staff asserts that the election of Democratic candidates in this area suffices for VRA. Appendix B is opaque regarding the actual non-White or Hispanic population in each district, but I presume that if they had created a majority-minority district they would have said so. In the draft alternative map, District 8 (Aurora, Commerce City, Brighton, and Thornton) has a 39.6% minority population and District 1 (Denver) has a 34.9% minority population. The proposals are similar in meeting this criterion.

Communities of Interest
    Staff presented a long list

of communities of interest. While keeping all of these intact would be ideal, drawing a map requires compromises based on geography and population. Many communities of interest overlap with each other, especially at their edges. This difficulty points to a reason to focus on existing subdivisions (county, city, and town boundaries): those boundaries are stable and overlap with shared public policy concerns. The preliminary commission map chooses to group the San Luis Valley, as far upstream as Del Norte and Creede, with Pueblo and the Eastern Plains rather than with the Western Slope/Mountains. To balance the population numbers, the preliminary commission map thus had to reach east in northern and central Colorado. The commission includes Canon City and Florence

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

A polygonal representation of the City and County of Denver's jurisdictional boundary. This datasets also includes all enclaves administered by other jurisdications that are located within the City and County of Denver's boundary.

Creates four districts with rural county constituencies. Only splits counties near the Denver metro area, plus a portion of El Paso next to Woodland Park. Max deviance.My focus was on low deviation numbers, resulting in a few odd boundaries which could be adjusted:* D2 portion of El Paso County could switch to D5, adding ~2600 deviation.* D2 portion east of Brighton could shift west, adding <1000 deviation.* With higher deviation, the D1/D6/D7 boundaries near southwest Denver could more closely match county boundaries.* Moffat County might be better aligned with D3 than D2, but this would add 13,000 deviation. Maybe shift Baca & Las Animas Counties to D6 and extend D2 into southwest Douglas and west Fremont Counties?Plan Information Plan name: North, East, Southwest, Central Description: Creates four districts with rural county constituencies. Only splits counties near the Denver metro area, plus a portion of El Paso next to Woodland Park. Max deviance <1200. Non-Denver municipalities only split at exclaves.Plan Objectives(1) Keep population deviation as low as possible.(2) Only deviate from county boundaries around the Denver metro area, plus US-24 adjacent to Woodland Park.(3) Don't split municipalities or CDPs, except exclaves (to keep districts contiguous) and the edges of Denver (to keep within population target).A variation on this map could relax goal #2 in order to put Moffat in CD-3, Baca & Las Animas in CD-6, and extend CD-2 into western Fremont and southwest Douglas Counties.Area/perimeter ratio for CD-2 could be increased by putting Brighton in CD-4 and the Weld County I-25 corridor in CD-2. Alternatively, Brighton could be in CD-8 if Thornton was split between CD-8 and CD-2.

Denver County, CO has a B wealth grade. Median household income: $92,582. Unemployment rate: 4.6%. Income grows 7.2% yearly.

This digital map shows bedding attitude symbols display over the geographic extent of surficial deposits and rock stratigraphic units (formations) as compiled by Trimble and Machette 1973-1977 and published in 1979 (U.S. Geological Survey Map I-856-H) under the Front Range Urban Corridor Geology Program. Trimble and Machette compiled their geologic map from published geologic maps and unpublished geologic mapping having varied map unit schemes. A convenient feature of the compiled map is its uniform classification of geologic units that mostly matches those of companion maps to the north (USGS I-855-G) and to the south (USGS I-857-F). Published as a color paper map, the Trimble and Machette map was intended for land-use planning in the Front Range Urban Corridor. This map recently (1997-1999), was digitized under the USGS Front Range Infrastructure Resources Project (see cross-reference). In general, the mountainous areas in the west part of the map exhibit various igneous and metamorphic bedrock units of Precambrian age, major faults, and fault brecciation zones at the east margin (5-20 km wide) of the Front Range. The eastern and central parts of the map (Colorado Piedmont) depict a mantle of unconsolidated deposits of Quaternary age and interspersed outcroppings of Cretaceous or Tertiary-Cretaceous sedimentary bedrock. The Quaternary mantle is comprised of eolian deposits (quartz sand and silt), alluvium (gravel, sand, and silt of variable composition), colluvium, and few landslides. At the mountain front, north-trending, dipping Paleozoic and Mesozoic sandstone, shale, and limestone bedrock formations form hogbacks and intervening valleys.

Map of Business improvement districts in Denver, CO.

This dataset is a point feature representing range points within the City and County of Denver. Range points are termini for range lines, which serve as offsets to right-of-way lines and block lines. Range points are typically located below surface streets.

Market Conditions, Affordable Housing Map, and Definitions & Data Notes.Instructions:Hover over graphics for data values Click on graphics to filter other graphicsUse dropdown menus to select multiple criteriaClick page index at bottom center of window to navigate directly to other pages Use the focus mode button in the upper right corner of any visual to view it in full screenResources & References Reports HOST Strategic Plan (2022-2026)2023 Annual Action Plan 2022 Annual Action Plan 2021 Annual Action Plan 2023 Annual Action Plan AddendumDashboards & Maps Five-Year Strategic Planning Efforts - City and County of Denver (denvergov.org)Tracking Vulnerability to Displacement (arcgis.com)Blueprint Denver Key Equity Concepts 2020 (arcgis.com)Neighborhood Dashboards - City and County of Denver (denvergov.org)HOST Website Department of Housing Stability - City and County of Denver (denvergov.org)

Feature Layer: Metro Denver Neighborhood Designations 2020Description: Adams County Health Department gathered these data about census tracts within neighborhood boundaries from the US Census data site. Source: 2020 U.S. CensusType: Polygon and pointGeography: Census tracts within the Metro Denver AreaProcess: Census tract information was downloaded from the US Census data site for 2020, and boundaries were dissolved along neighborhood boundaries for the Metro Denver area. Description provided by Adams County Health Department.

The City Engineering Quarter Section Map Index contains information regarding City Engineering quarter section numbers and Public Land Survey System (PLSS) information for each quarter section in the City and County of Denver, as well as a few of the surrounding section quarters. For each quarter section of the PLSS in the City and County of Denver, the City Engineering (later the City Surveyor's office) developed and maintained a linen sheet depicting subdivision, lot, ordinance, and easement data in that quarter section. Using Broadway and Colfax Avenue as the dividing lines, the CCD is broken into four quadrants, and the quarter sections for each quadrant are numbered beginning with 1. NOTE: Maintenance of these quarter section sheets was discontinued after 1996 due to the development of the CCD GIS.

Disclaimer

ACCESS CONSTRAINTS:

This data set is provided as read-only. Contact the GIS Data Administrator for more information on distribution requirements/restrictions.

USE CONSTRAINTS:

The City and County of Denver is not responsible and shall not be liable to the user for damages of any kind arising out of the use of data or information provided by the City and County of Denver, including the installation of the data or information, its use, or the results obtained from its use.

ANY DATA OR INFORMATION PROVIDED BY THE City and County of Denver IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Data or information provided by the City and County of Denver shall be used and relied upon only at the user's sole risk, and the user agrees to indemnify and hold harmless the City and County of Denver, its officials, officers and employees from any liability arising out of the use of the data/information provided.

NOT FOR ENGINEERING PURPOSES

The locations of 1,879 coal mines and facilities, 8 uranium mines, and 1,965 mines and processing plants for 74 types of nonfuel minerals and materials are shown with symbols on both a large multicolored lithologic map and eight smaller maps. With the exception of certain commodities, such as gold, silver, gemstones, and coal, all mines and plants are shown for which production was reported or estimated in 1997. These localities account for most of the fuel and nonfuel minerals and materials produced in the United States in 1997, other than crushed stone, sand and gravel, and common clay. The poster-size map (Map I-2654) is available for purchase from the U.S. Geological Survey Map Distribution, Box 25286, Federal Center, Denver, CO 80225. Internet versions of the map and seven commodity grouping maps that contain data for nonfuel minerals and materials are available. The information presented in the three data documents represents basic data about the 1,965 mines and processing plants shown on the map. Included in each of the three documents is company name, site name, State, county, commodity, and whether the location is a mine, processing plant, or both for each of the locations shown on the map. The data documents contain the basic data arranged by commodity, State, and county. For locations where multiple commodities are produced (for example, a mine that produces both gold and silver), the commodities are listed alphabetically. The value figure shows estimates of the value of nonfuel minerals produced in the United States in 1997. These estimates are presented in descending order by State.

The data set for the Butler Peak quadrangle has been prepared by the Southern California Areal Mapping Project (SCAMP), a cooperative project sponsored jointly by the U.S. Geological Survey and the California Division of Mines and Geology, as part of an ongoing effort to utilize a Geographical Information System (GIS) format to create a regional digital geologic database for southern California. This regional database is being developed as a contribution to the National Geologic Map Data Base of the National Cooperative Geologic Mapping Program of the USGS. Development of the data set for the Butler Peak quadrangle has also been supported by the U.S. Forest Service, San Bernardino National Forest.

The digital geologic map database for the Butler Peak quadrangle has been created as a general-purpose data set that is applicable to other land-related investigations in the earth and biological sciences. For example, the U.S. Forest Service, San Bernardino National Forest, is using the database as part of a study of an endangered plant species that shows preference for particular rock type environments. The Butler Peak database is not suitable for site-specific geologic evaluations at scales greater than 1:24,000 (1 in = 2,000 ft).

This data set maps and describes the geology of the Butler Peak 7.5' quadrangle, San Bernardino County, California. Created using Environmental Systems Research Institute's ARC/INFO software, the data base consists of the following items: (1) a map coverage showing geologic contacts and units,(2) a scanned topographic base at a scale of 1:24,000, and (3) attribute tables for geologic units (polygons), contacts (arcs), and site-specific data (points). In addition, the data set includes the following graphic and text products: (1) A PostScript graphic plot-file containing the geologic map on a 1:24,000 topographic base accompanied by a Description of Map Units (DMU), a Correlation of Map Units (CMU), and a key to point and line symbols; (2) PDF files of the DMU and CMU, and of this Readme, and (3) this metadata file.

The geologic map data base contains original U.S. Geological Survey data generated by detailed field observation and by interpretation of aerial photographs. The map was created by transferring lines from the aerial photographs to a 1:24,000 mylar orthophoto-quadrangle and then to a base-stable topographic map. This map was then scribed, and a .007 mil, right-reading, black line clear film made by contact photographic processes.The black line was scanned and auto-vectorized by Optronics Specialty Company, Northridge, CA. The non-attributed scan was imported into ARC/INFO, where the database was built. Within the database, geologic contacts are represented as lines (arcs), geologic units as polygons, and site-specific data as points. Polygon, arc, and point attribute tables (.pat, .aat, and .pat, respectively) uniquely identify each geologic datum and link it to other tables (.rel) that provide more detailed geologic information.

This file is a digital polygon representation of the areal extent of abandoned underground coal mines and surface mines in the Boulder-Weld coal field, Denver Basin, Colorado. This file was created as part of the Front Range Infrastructure Resources Project (FRIRP) of the USGS, and provides information pertaining to energy resource issues within the Colorado Front Range urban corridor in and near the Denver metro area. These data contributed to the publication titled as follows: Maps showing the extent of mining, locations of mine shafts, adits, air shafts, and bedrock faults, and thickness of overburden above abandoned coal mines in the Boulder-Weld coal field, Boulder, Weld, and Adams counties, Colorado: U.S. Geological Survey Geologic Investigations Map I-2735, 1:48000-scale.

The zoning boundaries layer is an integral part of the planning and zoning data in the City and County of Denver Geographic Information System. This data is used by the Planning Department in case review, enforcement, and long range planning. GIS data layers are accessed by personnel in most City departments for basic applications such as viewing, querying, and map output production.

Census tracts are small, relatively permanent geographic entities within counties (or the statistical equivalents of counties) delineated by a committee of local data users. Generally, census tracts have between 2,500 and 8,000 residents and boundaries that follow visible features. When first established, census tracts are to be as homogeneous as possible with respect to population characteristics, economic status, and living conditions. (www.census.gov)

This database and accompanying plot files depict the distribution of geologic materials and structures at a regional (1:100,000) scale. The report is intended to provide geologic information for the regional study of materials properties, earthquake shaking, landslide potential, mineral hazards, seismic velocity, and earthquake faults. In addition, the report contains new information and interpretations about the regional geologic history and framework. However, the regional scale of this report does not provide sufficient detail for site development purposes. In addition, this map does not take the place of fault-rupture hazard zones designated by the Oregon State Geologist. Similarly, the database cannot be used to identify or delineate landslides in the region.

This digital map database, largely compiled from new mapping by the authors, represents the general distribution of bedrock and surficial deposits of the Roseburg 30 x 60 minute quadrangle along the southeastern margin of the Oregon Coast Range and its tectonic boundary with Mesozoic terranes of the Klamath Mountains. Together with the accompanying text files as PDF (rb_geol.pdf), it provides current information on the geologic structure and stratigraphy of the area covered. The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The scale of the source maps is 1:24,000, but the Quaternary contacts and structural data have been much simplified for the 1:100,000-scale map and database. The spatial resolution (scale) of the database is 1:100,000 or smaller.