探地雷达在沙漠研究中的应用综述

Application of Ground Penetrating Radar to Desert Research

沙丘层序的建立一直是风沙地貌与沙漠第四纪地质研究中的一个难点问题,而揭示沙丘沉积构造是解决该问题的基础和关键。探地雷达(GPR)是近年兴起的探测沙丘沉积构造的较新和较有效的手段,因风成沙沉积具有均一性好、低电导性、低含水性及低密度性等特点,使GPR在沙丘探测中得到良好的探测效果。借助GPR可研究:(1)一般沙丘的构造和层序、高大沙丘的浅层构造与层序、横向沙山的较完整层序等;(2)沙丘历史时期的移动方向和速率、沙丘的发育过程;(3)沙丘与沙漠的环境变化过程;(4)沙丘和沙漠的水文信息等。在应用过程中,需要注意沙丘含水量、电磁波频率选择、杂波干扰、波速理论值与实际偏差、数据处理和图像解译等方面的问题。目前,GPR在沙漠研究中尚未普及,本文旨在通过综述其在沙漠研究中的进展和存在问题,以期促进GPR在沙丘发育过程和沙漠演化过程研究中的应用。

It is a difficult problem for Aeolian Geomorphology and Quaternary Geology on desert research to construct dune strata sequence, while revealing dunes＂ sedimentary structure is the foundation and key of solving the problem. Ground Penetrating Radar（GPR） is an relatively new and effective instrument to detect dunes＂ sedimentary structure in recent years, because aeolian sedimentary is characterized by good homoge- nicity, low conduction, low water content and low density, which makes GPR do a good job in dune detec- ting. Some research could be conducted by GPR as follow： （1） sedimentary structure and strata sequence of small dunes, shallow sedimentary structure and strata sequence of huge dunes, and complete strata sequence of transverse mage-dunes; （Z） the direction and velocity of sand dunes migration in history; （3） the envi- ronment change of dunes and desert development. （4） the hydrology of dunes and desert. In application, we need to notice dunes＇ water content, frequency determination of GPR, noise interference, the difference of velocity between theoretical and factual value, data processing and interpretation of GPR image. At present, GPR is not widely used on desert research. By summarizing research progress and problems of GPR on des- ert research, it is hoped to promote its application in the research of dune and desert.