<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31352114</termId><termName>undersea troughs</termName><termType>PT</termType><termNote><![CDATA[ Depressions on the sea floor with characteristically flat bottoms and steep sides; usually more shallow than undersea trenches. ]]></termNote><termCreatedDate>2026-03-30 20:35:01</termCreatedDate><relation><relationType>UF</relationType><termId>31352115</termId><termName>troughs, undersea</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31352116</termId><termName>undersea trough</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31324173</termId><termName>undersea landforms</termName><termType>PT</termType></relation></term>  </Zthes>