<descriptor thcode="2"><thesaurus thcode="2" name="USGS Thesaurus" scope="Topics and methods of scientific study carried out by USGS, with product types, scientific disciplines, geologic time, and types of institutional structure and activities.  Broad and shallow, used to help people find scientific information." creator="U.S. Geological Survey" rights="Public domain" edition="2.0" date="2020-01-09" codetype="number" prefix="topic" uri="https://www2.usgs.gov/science/USGSThesaurus" tblname="term" nonpref="nonpref" relterm="relterm" root_code="1" contact="pschweitzer"><category><term thcode="25" code="29" name="distinct labels" parent="26" scope="Preferred labels (descriptor texts) are distinct within the thesaurus. A concept can be specified either by its unique identifier (code) or by the text of its descriptor."/><term thcode="25" code="16" name="hierarchical" parent="11" scope="Substantive broader-narrower relationships exist among the terms."/><term thcode="25" code="13" name="transitive" parent="12" scope="Narrower terms have an &quot;is a&quot; relationship with their broader terms, and generally can be described as part-of, type-of, or instance-of the broader term."/><term thcode="25" code="21" name="disciplines" parent="2" scope="Broad categories of human inquiry or activity, such as scientific disciplines."/><term thcode="25" code="20" name="methods" parent="2" scope="Actions taken to obtain or analyze information"/><term thcode="25" code="19" name="organizational functions" parent="2" scope="Things that organizations do, typically including various types of programs, projects, and services."/><term thcode="25" code="7" name="temporal" parent="2" scope="Terms indicate periods of time, such as chronostratigraphic units, named historical periods or intervals surrounding known historical events, or seasons."/><term thcode="25" code="5" name="theme" parent="2" scope="Terms indicate domains of human concern, such as scientific discipline, societal problems, or characteristics of earth, space, oceans, and living things."/><term thcode="25" code="29" name="distinct labels" parent="26" scope="Preferred labels (descriptor texts) are distinct within the thesaurus. A concept can be specified either by its unique identifier (code) or by the text of its descriptor."/><term thcode="25" code="16" name="hierarchical" parent="11" scope="Substantive broader-narrower relationships exist among the terms."/><term thcode="25" code="13" name="transitive" parent="12" scope="Narrower terms have an &quot;is a&quot; relationship with their broader terms, and generally can be described as part-of, type-of, or instance-of the broader term."/><term thcode="25" code="21" name="disciplines" parent="2" scope="Broad categories of human inquiry or activity, such as scientific disciplines."/><term thcode="25" code="20" name="methods" parent="2" scope="Actions taken to obtain or analyze information"/><term thcode="25" code="19" name="organizational functions" parent="2" scope="Things that organizations do, typically including various types of programs, projects, and services."/><term thcode="25" code="7" name="temporal" parent="2" scope="Terms indicate periods of time, such as chronostratigraphic units, named historical periods or intervals surrounding known historical events, or seasons."/><term thcode="25" code="5" name="theme" parent="2" scope="Terms indicate domains of human concern, such as scientific discipline, societal problems, or characteristics of earth, space, oceans, and living things."/></category><altlabel><altlabel>USGSThesaurus</altlabel><altlabel>USGSThesaurus</altlabel></altlabel></thesaurus><term thcode="2" code="798" name="nonmetallic mineral resources" parent="745" scope="Useful mineral deposits that are not metals.  Includes materials used for construction, decoration, fuel, and industrial purposes."/><uf><usefor name="industrial mineral resources"/><usefor name="industrial minerals"/></uf><bt><term thcode="2" code="745" name="mineral resources" parent="777" scope="Natural occurrences of useful inorganic elements or compounds."/><term thcode="2" code="777" name="natural resources" parent="1174" scope="Stocks of anything naturally occurring that have a beneficial use for man including economic, nutritional, recreational, aesthetic, and other benefits."/><term thcode="2" code="1174" name="topics" parent="1" scope="Themes, subjects, and concerns for which USGS information resources are relevant."/><term thcode="2" code="1" name="Categories" scope="Thematic terms for categorizing information resources.  This thesaurus is intended to support finding and understanding scientific information."/></bt><nt><term thcode="2" code="2302" name="barite" parent="798" scope="Mineral commodity barium sulfate used in many applications where a high-density non-metallic subsance is needed, such as drilling mud and medical technology."/><term thcode="2" code="132" name="building stone resources" parent="798" scope="Deposits of rocks used in construction, including crushed stone and dimension stone. Dimension stone includes limestone and granite, quarried in large blocks, and shaped in cubes, panels and other forms."/><term thcode="2" code="2303" name="fluorite" parent="798" scope="Mineral comodity calcium fluoride used in industrial applications and to produce hydrofluoric acid."/><term thcode="2" code="429" name="gem resources" parent="798" scope="Deposits of rare minerals prized for their color, durability, sparkle, and clarity when cut and polished and used as ornaments or jewelry."/><term thcode="2" code="2304" name="graphite" parent="798" scope="Mineral commodity composed of carbon arranged in sheet structures used in many ways, most recently in battery technology."/></nt><rt><term thcode="2" code="164" name="clay deposits" parent="1199" scope="Fine-grained sedimentary soil deposits, containing hydrated silicas of aluminum, that are plastic and sticky when wet and harden when heated."/><term thcode="2" code="312" name="economic geology" parent="464" scope="Scientific study of the formation, location, and use of marketable geologic materials including fuels, metals, minerals, and water."/><term thcode="2" code="500" name="gravel deposits" parent="1199" scope="Alluvial accumulations of small unconsolidated rock fragments, such as pebbles and cobbles, used in construction as fill, ground cover, or aggregate for concrete."/><term thcode="2" code="724" name="metallic mineral resources" parent="745" scope="Resources from which ductile, malleable, opaque,and reflective metals that are also good heat and electricity conductors can be extracted."/><term thcode="2" code="1011" name="sand deposits" parent="1199" scope="Deposits of loose particles of rock or mineral (sediment) that range in size from 0.0625-2.0 millimeters in diameter."/></rt></descriptor>