Would you like to know the location of active mines in your State and how they are spatially related to geologic and geophysical data? Need to know the location of geologic faults or unconsolidated sediments? This information and much more can be found on the Mineral Resources On-Line Spatial Data Web site (http://mrdata.usgs.gov/). This Internet-based system allows interested customers anywhere in the world to download accurate, up-to-date mineral-resource-related data at any time. Decisionmakers and public policy regulators will find this information particularly useful as it is relevant to resource sustainability, land stewardship, environmental assessment, the economy, and public health. All data in the system are spatially located (i.e., referenced to geographic locations) so that people with Internet access and a modern Web browser can easily produce maps with the overlays they choose for any region in the world.
Datasets available on the web site include geologic and lithologic maps; gravity, magnetic, radiometric, and derivative geophysical maps; mineral-resources data; geochemical data; and a selection of base-map layers depicting land-use, hydrography, topography, and cultural features.
The overall goal of the data-delivery project is to provide comprehensive coverage of the United States, State by State, with consistent, seamless, and complete digital datasets necessary for regional- and national-scale research and land-planning activities. The spatial data delivery system is being developed in cooperation with other Federal and State agencies.
How does the system work?
The Web-based access system includes a limited Geographic Information System (GIS) that is displayed within a Web browser window. The system is platform independent; it can work with any operating system on any hardware. The application allows flexible, interactive map creation and display and downloading of data from the Mineral Resources Program's major databases.
How do I prepare a map?
The public-access Web site (http://mrdata.usgs.gov/) allows map preparation using the following functions:
- Direct browsing of the data in a spatial context
- Interactive, on-screen, user-controlled map creation
- Interactive query and subset selection
- Tabular display of selected portions of datasets
- Download of user-defined maps as print/plot files
- Download of publicly available datasets for offline processing
Figure 1 is a map that was generated using the Mineral Resources On-Line Spatial Data Web site to find geologic information about a specific location in central Colorado. The "screen capture" in figure 1 shows menu selections that were made and the resulting map that was produced.
Figure 1 - Geologic map of central Colorado generated using the USGS Mineral Resources On-Line Spatial Data Web site, http://mrdata.usgs.gov/. Users are able to determine individual map units. The unit Yp, in the central part of the map, represents rocks of the Pike's Peak batholith. Larger version of figure 1.
To create the map in figure 1, use the following steps:
- Select the State of Colorado from the Web site home page, (http://mrdata.usgs.gov/).
- Select data layers to be displayed on the map. Select information (layers) of interest you from the left column by clicking on the boxes. Selected boxes have red check marks. Layers selected in this example include: map of United States, active mines and mineral plants, major cities, county outlines, geology from the Geologic Map of Colorado (Tweto, 1979), and major faults from the Geologic Map of the United States (King and Beikman, 1974).
- Select central Colorado as the study area using the "zoom-in" feature (magnifier with plus sign). Please note that "Map Display Help," at the bottom of the window, has explanations of the various tools available in this GIS.
- Click on "Colorado geology" to make it the active layer and select the "identify" function ("i" button) to display more information about a specific feature on the geologic map.
- Select a polygon from the geologic map to display the name of the map unit (Yp, in the example). This opens the "Identify Results" window in figure 1.
- Request the legend for the Colorado geology layer by clicking on the blue box with the question mark next to Colorado geology in the left column of the main window. This opens a window that contains the legend for the geologic map. The results show that map unit Yp represents rocks of Pike's Peak batholith.
Figure 2 shows a plot of an on-screen map and its legend. The on-screen map included the following data layers: geology, major faults, counties, cities, sample locations of igneous rocks including geochemical analyses, locations of mineral occurrences from mineral databases, and locations of active mines and mineral plants. After creating the desired map on-screen and selecting the "print" function, the title of the map and optional features were chosen in the "Layout Options" window (fig. 3).
Figure 2 - Geologic map and legend of the mineral deposits of the northern part of the Pike's Peak batholith in central Colorado was generated from the USGS Mineral Resources On-Line Spatial Data Web site. Larger version of figure 2.
Figure 3 - Window of layout options used to generate map and legend in figure 2.
For the map in figure 2, two pages were created, one for the map and another for the map legend. The map legend identifies only those features on layers that appear within the map outline defined by the user.
These examples briefly describe a few of the many features and data sets currently available on the Web site. Please return to the Web site often to take advantage of new features and new and updated data sets.
King, P.B., and Beikman, H.M., 1974, Geologic Map of United States: U.S. Geological Survey, 2 plates, scale 1:2,500,000.
Tweto, Ogden, 1979, Geologic Map of Colorado: U.S. Geological Survey, Special Geologic Map, scale 1:500,000.
For more information, contact
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