<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31317547</termId><termName>seismic reflection surveying</termName><termType>PT</termType><termNote><![CDATA[ Seismic reflection surveying is a form of geophysical surveying based on the principle that acoustic energy imparted into the earth by an impact source (such as a sledgehammer or explosives) will bounce, or "reflect," off subsurface interfaces. Seismographs and acoustic sensors ("geophones") record the reflections. Reflection seismic techniques study the arrival times, amplitude, and shape of the reflected waves. ]]></termNote><termCreatedDate>2026-03-30 20:25:30</termCreatedDate><relation><relationType>UF</relationType><termId>31317548</termId><termName>surveying, seismic reflection</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31304569</termId><termName>surveying</termName><termType>PT</termType></relation><relation><relationType>RT</relationType><termId>31436626</termId><termName>seismology</termName><termType>PT</termType></relation></term>  </Zthes>