砂岩型铀矿含矿砂体与围岩波阻抗差异初探——以哈达图矿区钻井岩心为例  

Preliminary Study on the Difference of Impedance Between Ore-bearing Sandstone and Wall Rock in Sandstone-type Uranium deposit:A Case Study of Well Core Samples in Hadatu Deposit

作　　者：李子伟[1] 吴曲波[1] 曹成寅[1] LI Ziwei;WU Qubo;CAO Chengyin(Beijing Research Institute of Uranium Geology,Beijing 100029,China)

机构地区：[1]核工业北京地质研究院,北京100029

出　　处：《铀矿地质》2020年第5期424-431,共8页Uranium Geology

基　　金：预先研究项目(编号:3210402);中核集团龙灿工程(二期)科研项目“二连基地砂岩型铀矿物化探三维探测技术研究”(编号:物LCEQ02)联合资助。

摘　　要：地震勘探方法在砂岩型铀矿勘查中能够有效解决地层、构造和砂体展布等地质问题,利用地震方法精细识别含矿砂体是很重要的一个研究方向,而含矿砂体与围岩的波阻抗差异是开展地震勘探技术研究的基础,因此在砂岩型铀矿地震勘探技术研究中,非常有必要了解砂岩型铀矿含矿砂体与围岩的波阻抗参数差异。笔者基于哈达图矿区的钻井岩心,利用合成制样方法制作了铀矿围岩样品和矿心样品,采用超声脉冲透射法测量了样品的纵横波速度,计算了围岩样品与矿心样品的纵横波阻抗参数,并进行了初步分析。结果表明:矿心样品的密度、纵横波速度和纵横波阻抗值均大于围岩样品,阻抗交汇图上能较好的区分围岩样品与矿心样品,说明能够通过波阻抗参数的差异区分含矿砂体与围岩,可以为砂岩型铀矿的地震勘探研究提供依据。Seismic exploration method can effectively solve geological problems such as the identification of sedimentary formation,structure and sand body distribution in the exploration of sandstone-type uranium deposit.The impedance difference between the ore-bearing sand body and the wall rock is the basis for seismic exploration,therefore,it is very important to understand the difference.Based on the drilling core samples in Qiharigetu depression of Erlian Basin,this paper studied the impedance difference of ore-bearing sand body and the wall rock using synthetic sample preparation methods.The elastic parameters of the sample were measured by ultrasonic pulse transmission,and calculated the P-wave impedance and S-wave impedance.Preliminary analysis of the measurement results showed that the density,P-wave velocity,S-wave velocity,P-wave impedance and S-wave impedance of the ore-bearing sandstone samples are greater than those of the wall rock samples,and the impedance cross-plot result can better distinguish the wall rock samples and core samples.This conclusion provided a basis for seismic exploration research of sandstone-type uranium.

关 键 词：砂岩型铀矿 含矿砂体 围岩 合成制样 波阻抗差异 

分 类 号：P619.14[天文地球—矿床学] P631.41[天文地球—地质学]