<?xml version="1.0" encoding="utf-8"?>
<metadata>
  <idinfo>
    <citation>
      <citeinfo>
        <origin>Oregon Department of Geology and Mineral Industries</origin>
        <pubdate>2026</pubdate>
        <title>Assay Point Locations by Public Land Survey System, Oregon.</title>
        <geoform>vector 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. This data set represents center points of: 1) the GIS Version of the Public Land Survey System including both rectangular and non-rectangular surveys; 2) County shapefile centroid; and 3) the BLM OR jurisdictional and cartographic state perimeter for Oregon. Assay points are located by township-range-section grid where samples were in surveyed areas at the time of collection and by county and/or State of Oregon for samples obtained from unsurveyed areas. 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>
    <spdom>
      <bounding>
        <westbc>-124.797466</westbc>
        <eastbc>-116.779583</eastbc>
        <northbc>46.228266</northbc>
        <southbc>41.924093</southbc>
      </bounding>
    </spdom>
    <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>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>The PLSS code was created and consists of the township and range down to the quarter-quarter section. No duplicates were found.</attraccr>
    </attracc>
    <logic>To make sure each record successfully and correctly joined to a PLSS point using the PLSS code, multiple iterations of joining tests were undertaken. After one join test, the PLSS code for the records that did not match to a point would be modified, so that in the next test, they would potentially join successfully. This was continued until all records matched with a point location. Next, the PLSS points dataset that matched at least one record was checked for duplicate points and/or points with duplicate PLSS codes. The duplicate points were then removed.</logic>
    <complete>This feature class only contains center points for PLSS, county, or the state of Oregon locations related to Assay Returns records.</complete>
    <posacc>
      <horizpa>
        <horizpar>PLSS center points are derived from the most recent published digital second division survey for the state of Oregon at the time of this project. Manual of Surveying Instructions for public land surveys have changed and evolved through the course of time. Therefore, actual location of assay center points may not exactly match the surveyed location at the time of collection and/or submission of samples.</horizpar>
      </horizpa>
    </posacc>
    <lineage>
      <srcinfo>
        <srccite>
          <citeinfo>
            <origin>Bureau of Land Management</origin>
            <pubdate>20240118</pubdate>
            <title>BLM OR Cadastral PLSS Second Division Polygon</title>
            <edition>Final</edition>
            <geoform>vector digital data</geoform>
            <pubinfo>
              <publish>Bureau of Land Management</publish>
            </pubinfo>
            <othercit>Bureau of Land Management (BLM), Oregon State Office</othercit>
            <onlink>https://gbp-blm-egis.hub.arcgis.com/maps/7359fe7bc21447cc9a854617721a9c55</onlink>
          </citeinfo>
        </srccite>
        <typesrc>online</typesrc>
        <srctime>
          <timeinfo>
            <sngdate>
              <caldate>20240124</caldate>
            </sngdate>
          </timeinfo>
          <srccurr>download</srccurr>
        </srctime>
        <srccitea>PLSS</srccitea>
      </srcinfo>
      <srcinfo>
        <srccite>
          <citeinfo>
            <origin>Bureau of Land Management</origin>
            <pubdate>20130130</pubdate>
            <title>BLM OR Oregon Washington State Boundary Polygon</title>
            <geoform>vector digital data</geoform>
            <pubinfo>
              <publish>Bureau of Land Management</publish>
            </pubinfo>
            <othercit>BLM (Bureau of Land Management), CFF (Cartographic Feature File), DLG (Digital Line Graph), DNR (Washington Department of Natural Resources), DRG (Digital Raster Graphic), FIPS (Federal Information Processing Standard), GCD (Geographic Coordinate Database layer), GCDB (Geographic Coordinate Data Base), HYD (WODDB Hydrologic Features layer), LLI (Landlines layer), USFS (U.S. Forest Service), USGS (U.S. Geological Survey), WODDB (Western Oregon Digital Data Base). The POCA layer is an integrated set of geographic- referencing data covering the state of Washington. It is derived from land surveys, DNR orthophotos, USGS 7.5' quadrangles, and DNR tract books.</othercit>
            <onlink>https://gbp-blm-egis.hub.arcgis.com/maps/7359fe7bc21447cc9a854617721a9c55</onlink>
          </citeinfo>
        </srccite>
        <typesrc>online</typesrc>
        <srctime>
          <timeinfo>
            <sngdate>
              <caldate>20130130</caldate>
            </sngdate>
          </timeinfo>
          <srccurr>publication</srccurr>
        </srctime>
        <srccitea>Oregon State</srccitea>
      </srcinfo>
      <srcinfo>
        <srccite>
          <citeinfo>
            <origin>Bureau of Land Management</origin>
            <pubdate>20150601</pubdate>
            <title>BLM OR County Boundaries Polygon</title>
            <geoform>vector digital data</geoform>
            <pubinfo>
              <publish>Bureau of Land Management</publish>
            </pubinfo>
            <othercit>Oregon BLM</othercit>
          </citeinfo>
        </srccite>
        <typesrc>online</typesrc>
        <srctime>
          <timeinfo>
            <sngdate>
              <caldate>20150601</caldate>
            </sngdate>
          </timeinfo>
          <srccurr>publication</srccurr>
        </srctime>
        <srccitea>Oregon County</srccitea>
      </srcinfo>
      <procstep>
        <procdesc>The PLSS data was the most-detailed location information on each assay PDF, the BLM OR Cadastral PLSS Second Division polygon dataset was downloaded from the BLM Geospatial Business Platform and used to designate assay point locations. The cadastral dataset was converted from polygons to points (centroids within) and a PLSS code was created within a field in the point attribute table. This field consists of the township and range down to the quarter-quarter section. This PLSS code format was replicated in the assay table using each assays PLSS location information. The code information was used as a primary key for relating the cadastral point locations to the assay table records. </procdesc>
        <srcused>PLSS; Oregon County; Oregon State</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>
  <spdoinfo>
    <direct>Vector</direct>
  </spdoinfo>
  <spref>
    <horizsys>
      <planar>
        <mapproj>
          <mapprojn>NAD_1983_HARN_Oregon_Statewide_Lambert_Feet_Intl</mapprojn>
          <lambertc>
            <stdparll>43.0</stdparll>
            <stdparll>45.5</stdparll>
            <feast>1312335.958005249</feast>
          </lambertc>
        </mapproj>
        <planci>
          <plandu>Foot</plandu>
        </planci>
      </planar>
      <geodetic>
        <horizdn>D North American 1983 HARN</horizdn>
        <ellips>GRS 1980</ellips>
        <semiaxis>6378137.0</semiaxis>
        <denflat>298.257222101</denflat>
      </geodetic>
    </horizsys>
  </spref>
  <eainfo>
    <detailed>
      <enttyp>
        <enttypl>AssayPointLocations</enttypl>
      </enttyp>
      <attr>
        <attrlabl>PLSS_ID</attrlabl>
        <attrdef>Primary key. Values are listed as Township Range Section Quarter Quarter as available otherwise County or State. Example: T37S R09W 09 SENW</attrdef>
        <attrdefs>Oregon Department of Geology and Mineral Industries</attrdefs>
      </attr>
    </detailed>
    <overview>
      <eaover>This data set represents center points of: 1) the GIS Version of the Public Land Survey System including both rectangular and non-rectangular surveys; 2) County shapefile centroid; and 3) the BLM OR jurisdictional and cartographic state perimeter for Oregon. Assay points are located by township-range-section grid where samples were in surveyed areas at the time of collection and by county and/or State of Oregon for samples obtained from unsurveyed areas.</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>
