<?xml version="1.0" encoding="utf-8"?>
<metadata>
  <idinfo>
    <citation>
      <citeinfo>
        <origin>Oregon Department of Geology and Mineral Industries</origin>
        <pubdate>2026</pubdate>
        <title>County Mine Records, Oregon.</title>
        <geoform>tabular digital data</geoform>
        <serinfo>
          <sername>Oregon Department of Geology and Mineral Industries Digital Data</sername>
          <issue>MILO-4</issue>
        </serinfo>
        <pubinfo>
          <pubplace>Portland, Oregon, USA</pubplace>
          <publish>Oregon Department of Geology and Mineral Industries</publish>
        </pubinfo>
        <onlink>https://www.oregon.gov/dogami/pages/default.aspx</onlink>
        <lworkcit>
          <citeinfo>
            <origin>Oregon Department of Geology and Mineral Industries</origin>
            <pubdate>2026</pubdate>
            <title>Mineral Information Layer for Oregon-Release 4 (MILO-4)</title>
            <edition>Release 4</edition>
            <serinfo>
              <sername>Oregon Department of Geology and Mineral Industries Digital Data</sername>
              <issue>MILO-4</issue>
            </serinfo>
            <pubinfo>
              <pubplace>Portland, Oregon, USA</pubplace>
              <publish>Oregon Department of Geology and Mineral Industries</publish>
            </pubinfo>
            <onlink>https://www.oregon.gov/dogami/pages/default.aspx</onlink>
          </citeinfo>
        </lworkcit>
      </citeinfo>
    </citation>
    <descript>
      <abstract>The Mineral Information Layer for Oregon-Release 4 (MILO-Release 4) is a geospatial database that stores and manages information regarding Oregon's mineral occurrences, prospects, and mines; it is the primary way in which the State extracts, researches, and displays its available historical mining and mineral resource information. The County Mine Records table houses the hyperlinks to mining records and reports in Adobe Portable Document Format (PDF), relates them with specific mine sites, and provides document title and mining district when available. Understand that recreation in or around inactive mine sites is extremely dangerous, and can result in serious injury or death. Stay out and stay alive!</abstract>
      <purpose>The purpose of this MILO-Release 4 is for use as reference material supporting local- to statewide-scale mineral resource and environmental assessments. These data provide a searchable catalogue with links to supporting digital documentation that allows users to extract, research, and display historical mining and mineral resource information.</purpose>
    </descript>
    <timeperd>
      <timeinfo>
        <sngdate>
          <caldate>08/01/1991-08/31/2024</caldate>
        </sngdate>
      </timeinfo>
    </timeperd>
    <status>
      <progress>Planned</progress>
      <update>Biennial</update>
    </status>
    <keywords>
      <theme>
        <themekt>ISO 19115 Topic Category</themekt>
        <themekey>geoscientificinformation</themekey>
      </theme>
      <theme>
        <themekt>Oregon Geospatial Enterprise Office Metadata Keyword Thesaurus</themekt>
        <themekey>stone</themekey>
        <themekey>metallic mineral</themekey>
        <themekey>industrial mineral</themekey>
        <themekey>mineral resource</themekey>
        <themekey>zeolite</themekey>
        <themekey>sand and gravel</themekey>
      </theme>
      <theme>
        <themekt>USGS Thesaurus</themekt>
        <themekey>geospatial datasets</themekey>
        <themekey>hazards</themekey>
        <themekey>hazard preparedness</themekey>
        <themekey>scientific interpretation</themekey>
        <themekey>time series datasets</themekey>
      </theme>
      <theme>
        <themekt>Custom</themekt>
        <themekey>MILO (Mineral Information Layer for Oregon)</themekey>
        <themekey>Mine</themekey>
        <themekey>Mineral fuel</themekey>
        <themekey>Aggregate</themekey>
        <themekey>Gemstone</themekey>
        <themekey>Borrow Pit</themekey>
        <themekey>Prospect</themekey>
        <themekey>Quarry</themekey>
        <themekey>Gravel Pit</themekey>
        <themekey>Mineral Occurrence</themekey>
      </theme>
      <place>
        <placekt>Oregon Geospatial Enterprise Office Metadata Keyword Thesaurus</placekt>
        <placekey>United States</placekey>
        <placekey>North America</placekey>
        <placekey>Oregon</placekey>
        <placekey>Baker</placekey>
        <placekey>Benton</placekey>
        <placekey>Clackamas</placekey>
        <placekey>Clatsop</placekey>
        <placekey>Columbia</placekey>
        <placekey>Coos</placekey>
        <placekey>Crook</placekey>
        <placekey>Curry</placekey>
        <placekey>Deschutes</placekey>
        <placekey>Douglas</placekey>
        <placekey>Gilliam</placekey>
        <placekey>Grant</placekey>
        <placekey>Harney</placekey>
        <placekey>Hood River</placekey>
        <placekey>Jackson</placekey>
        <placekey>Jefferson</placekey>
        <placekey>Josephine</placekey>
        <placekey>Klamath</placekey>
        <placekey>Lake</placekey>
        <placekey>Lane</placekey>
        <placekey>Lincoln</placekey>
        <placekey>Linn</placekey>
        <placekey>Malheur</placekey>
        <placekey>Marion</placekey>
        <placekey>Morrow</placekey>
        <placekey>Multnomah</placekey>
        <placekey>Polk</placekey>
        <placekey>Sherman</placekey>
        <placekey>Tillamook</placekey>
        <placekey>Umatilla</placekey>
        <placekey>Union</placekey>
        <placekey>Wallowa</placekey>
        <placekey>Wasco</placekey>
        <placekey>Washington</placekey>
        <placekey>Wheeler</placekey>
        <placekey>Yamhill</placekey>
      </place>
    </keywords>
    <accconst>None</accconst>
    <useconst>REPORT DATA: This product is for informational purposes and may not have been prepared for or be suitable for legal, engineering, or surveying purposes. Users of this information should review or consult the primary data and information sources to ascertain the usability of the information. This publication cannot substitute for site-specific investigations by qualified practitioners. Site-specific data may give results that differ from the results shown in the publication. See the accompanying text report for more details on the limitations of the methods and data used to prepare this publication.</useconst>
    <ptcontac>
      <cntinfo>
        <cntorgp>
          <cntorg>Oregon Department of Geology and Mineral Industries </cntorg>
        </cntorgp>
        <cntaddr>
          <addrtype>mailing and physical address</addrtype>
          <address>800 NE Oregon Street Suite 965</address>
          <city>Portland</city>
          <state>Oregon</state>
          <postal>97232</postal>
          <country>USA</country>
        </cntaddr>
        <cntvoice>1 971 673 1555</cntvoice>
        <cntfax>1 971 673 1562</cntfax>
        <cntemail>dogami-info@dogami.oregon.gov</cntemail>
        <cntinst>When contacting DOGAMI about this data set, please reference the data set title or other identifying information in your correspondence. DOGAMI publications can be downloaded from https://www.oregon.gov/dogami/pages/default.aspx</cntinst>
      </cntinfo>
      <cntinfo>
        <cntperp>
          <cntper>Carlie J.M. Azzopardi</cntper>
          <cntorg>Oregon Department of Geology and Mineral Industries</cntorg>
        </cntperp>
      </cntinfo>
    </ptcontac>
    <datacred>This update and release of MILO-4 was supported through a grant from the National Geological and Geophysical Data Preservation Program (NGGDPP) under cooperative agreement number G23AP00218-01 (2023). Additional funds were provided by the State of Oregon.</datacred>
    <secinfo>
      <secclass>Unclassified</secclass>
    </secinfo>
  </idinfo>
  <dataqual>
    <attracc>
      <attraccr>Attribute accuracy is tested by manual comparison of the source and hard copy scans. However some PDF's contain pieces of documentation that are not related to the specific mine listed in the title and other PDF's contain documentation on multiple mines and mine synonyms. Fixing these errors was beyond the scope of this project and no attempt has been made to fix these errors. The detail level (e.g. Title) of the source material and interpretation procedures for capturing that source affect the quality of the data. Not all fields contain applicable attribute and are filled in as "unknown". Field checking of the data was not performed.</attraccr>
    </attracc>
    <logic>Due to the many to many relationship some CountyMineRecords_ID's may be repeated, and/or some MILO points may be repeated. However no duplicated features exist although individual features may share some of the same attribute(s), but have differences in unique identifiers. Although the data were collected and reported by numerous people, the descriptions provided follow a consistent structure or terminology though the content may vary widely.</logic>
    <complete>Not all fields are attributed in the data set. These data are scans of the literature originally found in DOGAMI published and unpublished hardcopy holdings, though some documents may not have been included, the coverage is statewide. The tabular data are presented in the form of rows representing the relationship of the maps, letters, news clippings, photographs, or reports to a specific MILO point. </complete>
    <lineage>
      <srcinfo>
        <srccite>
          <citeinfo>
            <origin>Oregon Department of Geology and Mineral Industries</origin>
            <pubdate>2020</pubdate>
            <title>Mineral Information Layer for Oregon, Release 3 [MILO-3]</title>
            <edition>Release 3</edition>
            <geoform>vector digital data</geoform>
            <serinfo>
              <sername>Oregon Department of Geology and Mineral Industries Digital Data</sername>
              <issue>MILO-3</issue>
            </serinfo>
            <pubinfo>
              <pubplace>Portland, Oregon</pubplace>
              <publish>Oregon Department of Geology and Mineral Industries</publish>
            </pubinfo>
            <othercit>McClaughry, J.D., Niewendorp, C.A., Franczyk, J. J., Duda, C. J. M., and Madin, I. P., 2020, Mineral Information Layer for Oregon, release 3 [MILO-3]: Oregon Department of Geology and Mineral Industries Digital Data Series MILO-3, Esri geodatabase. Superseded by DOGAMI MILO, release 4.</othercit>
            <onlink>https://pubs.oregon.gov/dogami/dds/p-MILO-3.htm</onlink>
          </citeinfo>
        </srccite>
        <typesrc>online</typesrc>
        <srctime>
          <timeinfo>
            <sngdate>
              <caldate>2020</caldate>
            </sngdate>
          </timeinfo>
          <srccurr>publication</srccurr>
        </srctime>
        <srccitea>MILO3</srccitea>
      </srcinfo>
      <srcinfo>
        <srccite>
          <citeinfo>
            <origin>Oregon Department of Geology and Mineral Industries</origin>
            <pubdate>20111215</pubdate>
            <title>Mining Records - Index</title>
            <geoform>tabular digital data</geoform>
            <pubinfo>
              <pubplace>Portland, Oregon</pubplace>
              <publish>Oregon Department of Geology and Mineral Industries</publish>
            </pubinfo>
            <othercit>Grey literature.</othercit>
            <onlink>https://www.oregon.gov/dogami/milo/Pages/index-miningrecords.aspx</onlink>
          </citeinfo>
        </srccite>
        <typesrc>online</typesrc>
        <srctime>
          <timeinfo>
            <sngdate>
              <caldate>20111215</caldate>
            </sngdate>
          </timeinfo>
          <srccurr>online</srccurr>
        </srctime>
        <srccitea>County records</srccitea>
      </srcinfo>
      <procstep>
        <procdesc>DOGAMI updated MILO's file structure in the MILO-3 update to adhere to the Geologic Map Schema (GeMS), designed by the U.S. Geological Survey. The schema can be found here (https://ngmdb.usgs.gov/Info/standards/GeMS/).
The subject field in the historical mining records table was compared to the SiteName in the MILO attribute table using the Fuzzy Lookup Add-In for Microsoft Excel. The Fuzzy Lookup Add-In was developed by Microsoft Research and performs fuzzy matching of textural data in Microsoft Excel. It was used to fuzzy join similar rows between two different tables. The matching process is susceptible to a wide variety of errors, including spelling inconsistencies, abbreviations, synonyms, and added/missing data. For instance, it might detect that the rows Mr. Andrew Hill, Hill, Andrew R. and Andy Hill all refer to the same underlying entity, returning a similar score along with each match. A very large portion of the MILO mine points in the MILO attribute table were not identified with a specific SiteName. For example, prospect, gravel pit, and other generic descriptions were not considered. Therefore, in preparation for Fuzzy Lookup, a modified list of 11,203 MILO mine sites, with specific a specific SiteName, was generated. The process of Fuzzy Lookup, considering the modified list of 11,203 MILO mine sites, generated 14,074 matches that had a similarity score of 75 percent or greater and a limitation of 20 matches of MILO mine points to each historical mining record. The modified list was then trimmed down to 4,695 likely matches where the mining record county matched the county that the MILO mine point fell within. This final step was done to avoid mismatches, where mine names matched, but where records referred to similarly named mines were in different parts of the state.
A combination of visual inspections was used to match historical mining records and MILO mine points using Esri ArcMap and Adobe Bridge. Specific features examined to assign possible matches as good, neutral, or bad match were mine name, document name, districts, Public Land Survey System (PLSS) location, and commodity. This examination included looking at the MILO mine points spatially in Esri ArcMap, looking in the attribute tables for matching information in Esri ArcMap, and viewing documents in Adobe Bridge to get identifying information from the actual document. Additionally, appropriate MILO mine point IDs were manually added as a good match when verifying nearby MILO mine points. After the first pass, all neutral assigned matches were given a second look and assigned either as a good or bad match. </procdesc>
        <srcused>County records</srcused>
        <proccont>
          <cntinfo>
            <cntorgp>
              <cntorg>Oregon Department of Geology and Mineral Industries</cntorg>
            </cntorgp>
            <cntaddr>
              <addrtype>mailing and physical address</addrtype>
              <address>800 NE Oregon Street Suite 965</address>
              <city>Portland</city>
              <state>Oregon</state>
              <postal>97232</postal>
              <country>USA</country>
            </cntaddr>
            <cntvoice>1 971 673 1555</cntvoice>
            <cntfax>1 971 673 1562</cntfax>
            <cntemail>dogami-info@dogami.oregon.gov</cntemail>
            <cntinst>When contacting DOGAMI about this data set, please reference the data set title or other identifying information in your correspondence. DOGAMI publications can be downloaded from https://www.oregon.gov/dogami/pages/default.aspx</cntinst>
          </cntinfo>
        </proccont>
      </procstep>
    </lineage>
  </dataqual>
  <eainfo>
    <detailed>
      <enttyp>
        <enttypl>CountyMineRecords</enttypl>
      </enttyp>
      <attr>
        <attrlabl>CountyMineRecords_ID</attrlabl>
        <attrdef>Primary key. Values =HD_0001, HD_0002, HD_0003, etc. Values may be repeated in the data set.</attrdef>
        <attrdefs>Oregon Department of Geology and Mineral Industries</attrdefs>
      </attr>
      <attr>
        <attrlabl>District</attrlabl>
        <attrdef>Mining district the county mine record was assigned. Some districts are formal, but most are informal.</attrdef>
        <attrdefs>Oregon Department of Geology and Mineral Industries</attrdefs>
      </attr>
      <attr>
        <attrlabl>DocumentName</attrlabl>
        <attrdef>Title assigned to the scanned document.</attrdef>
        <attrdefs>Oregon Department of Geology and Mineral Industries</attrdefs>
      </attr>
      <attr>
        <attrlabl>Hyperlink</attrlabl>
        <attrdef>Hyperlink to the online document.</attrdef>
        <attrdefs>Oregon Department of Geology and Mineral Industries</attrdefs>
      </attr>
    </detailed>
    <overview>
      <eaover>The County Mine Records table houses the hyperlinks to mining records and reports in Adobe Portable Document Format (PDF), relates them with specific mine sites, and provides document title and mining district when available.</eaover>
    </overview>
  </eainfo>
  <distinfo>
    <distrib>
      <cntinfo>
        <cntorgp>
          <cntorg>Oregon Department of Geology and Mineral Industries</cntorg>
        </cntorgp>
        <cntaddr>
          <addrtype>mailing and physical address</addrtype>
          <address>800 NE Oregon Street Suite 965</address>
          <city>Portland</city>
          <state>Oregon</state>
          <postal>97232</postal>
          <country>USA</country>
        </cntaddr>
        <cntvoice>1 971 673 1555</cntvoice>
        <cntfax>1 971 673 1562</cntfax>
        <cntemail>dogami-info@dogami.oregon.gov</cntemail>
        <cntinst>When contacting DOGAMI about this data set, please reference the data set title or other identifying information in your correspondence. DOGAMI publications can be downloaded from https://www.oregon.gov/dogami/pages/default.aspx</cntinst>
      </cntinfo>
    </distrib>
    <distliab>Although these data have been processed successfully on a computer system at the Oregon Department of Geology and Mineral Industries, no warranty expressed or implied is made by DOGAMI regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty.</distliab>
    <stdorder>
      <digform>
        <digtinfo>
          <formname>"GDB" Esri File Geodatabase</formname>
        </digtinfo>
      </digform>
    </stdorder>
    <availabl>
      <timeinfo>
        <sngdate>
          <caldate>08/01/1991-08/31/2024</caldate>
        </sngdate>
      </timeinfo>
    </availabl>
  </distinfo>
  <metainfo>
    <metd>2024-08-31 00:00:00</metd>
    <metc>
      <cntinfo>
        <cntorgp>
          <cntorg>Oregon Department of Geology and Mineral Industries</cntorg>
        </cntorgp>
        <cntaddr>
          <addrtype>mailing and physical address</addrtype>
          <address>800 NE Oregon Street Suite 965</address>
          <city>Portland</city>
          <state>Oregon</state>
          <postal>97232</postal>
          <country>USA</country>
        </cntaddr>
        <cntvoice>1 971 673 1555</cntvoice>
        <cntfax>1 971 673 1562</cntfax>
        <cntemail>dogami-info@dogami.oregon.gov</cntemail>
        <cntinst>When contacting DOGAMI about this data set, please reference the data set title or other identifying information in your correspondence. DOGAMI publications can be downloaded from https://www.oregon.gov/dogami/pages/default.aspx</cntinst>
      </cntinfo>
    </metc>
    <metstdn>Oregon Department of Geology and Mineral Industries Metadata Standard</metstdn>
    <metstdv>1.4</metstdv>
    <metac>None</metac>
    <metuc>None</metuc>
    <metsi>
      <metscs>None</metscs>
      <metsc>None</metsc>
      <metshd>None</metshd>
    </metsi>
  </metainfo>
</metadata>
