<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31412368</termId><termName>sapropel</termName><termType>PT</termType><termNote><![CDATA[ A nitrogen-rich, combustible, sludge-like black sedimentary deposit that occurs as a result of the decomposition of microorganisms in anaerobic conditions on the bottoms of lakes and seas. Compressed into hard rock, sapropel becomes oil shale or sapropelic coal. ]]></termNote><termCreatedDate>2026-03-30 20:50:52</termCreatedDate><relation><relationType>UF</relationType><termId>31412369</termId><termName>sapropels</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31375558</termId><termName>sediment</termName><termType>PT</termType></relation><relation><relationType>RT</relationType><termId>31438530</termId><termName>shale</termName><termType>PT</termType></relation></term>  </Zthes>