<descriptor thcode="62"><thesaurus thcode="62" name="Coastal and Marine Ecological Classification Standard" scope="Categories of ecosystems for coastal, estuarine, and marine environments." creator="FGDC" rights="public domain" date="2017-05-10" codetype="alpha" prefix="cmecs" uri="https://www2.usgs.gov/science/CMECS" tblname="cmecs" root_code="root" contact="pschweitzer"><category><term thcode="25" code="16" name="hierarchical" parent="11" scope="Substantive broader-narrower relationships exist among the terms."/><term thcode="25" code="16" name="hierarchical" parent="11" scope="Substantive broader-narrower relationships exist among the terms."/></category><altlabel><altlabel>CMECS</altlabel><altlabel>CMECS</altlabel><altlabel>Coastal and Marine Ecological Classification Standard (CMECS)</altlabel><altlabel>Coastal and Marine Ecological Classification Standard (CMECS)</altlabel></altlabel></thesaurus><term thcode="62" code="GC-206" name="Halo" parent="GC-199" scope="Geoform Type: The zone of low-relief, generally bare, sand surrounding Patch Coral Reefs. Halos are often formed by the action of grazing herbivores in the adjacent patch reef itself."/><bt><term thcode="62" code="GC-199" name="Shallow/Mesophotic Coral Reef" parent="GC-184" scope="Geoform: Light-dependent coral reefs that occur within the photic zone (the mesophotic reefs occur in the lower part of this zone at depths of 30 - 150 meters). (http://www.mesophotic.org)."/><term thcode="62" code="GC-184" name="Biogenic" parent="GC-C052" scope="Geoform Origin: Biogenic geoforms are physical features and landforms that were created by the action of living organisms (bioherms). ..."/><term thcode="62" code="GC-C052" name="Geoform (levels 1 and 2 subcomponents)" parent="GC-C005"/><term thcode="62" code="GC-C005" name="Geoform" parent="root"/><term thcode="62" code="root" name="CMECS" scope="Coastal and Marine Ecological Classification Standard: Category terms encompassing waters from the head of tide or inland incursion of ocean salinity to the splash zone of the coasts to the deepest portions of the oceans and the deep waters of the Great Lakes."/></bt></descriptor>