<?xml version="1.0" encoding="utf-8"?><mads xmlns="http://www.loc.gov/mads/" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mads/
mads.xsd"><authority><topic authority="http://AATesaurus.cultura.gencat.cat/aat/getty_en">geological formations</topic></authority><related type="narrower"><topic>speleothems</topic></related><related type="broader"><topic>geological concepts</topic></related><variant type="other"><topic>formations</topic></variant><variant type="other"><topic>geologic formations</topic></variant><variant type="other"><topic>geological formation</topic></variant><variant type="other"><topic>stratigraphic formations</topic></variant> <note xml:lang="en"><![CDATA[ In geology, the fundamental units of lithostratigraphy comprising distinctive assemblages, layers, or units of rock in an area, characterized as being of homogeneous origin and appearance. The designation and limits of a given geological formation may vary, depending upon the criteria imposed by the cataloging body. ]]></note></mads>