直流电阻率法中不同装置的灵敏度探讨

The Discussion on Sensitivity of Different Arrays in DC Resistivity Method

直流电阻率法勘探是根据岩石和矿石导电性的差别,通过研究地下岩、矿石电阻率变化,进行地下介质探查的一种方法。本文介绍了直流电阻率法中灵敏度的基本概念,计算公式及其实际意义。文中以二极装置和三极装置为例,绘制不同电极距下的灵敏度曲线,并且对灵敏度曲线进行比较分析。然后以一个简单地电模型为例,采用软件绘制不同装置下的灵敏度剖面图,对不同装置的灵敏度情况进行简单的比较,简单分析了灵敏度与探测深度的关系。灵敏度信息包含了装置在横向和纵向的分辨率,绘制灵敏度曲线和剖面图有助于人们了解装置对地下介质的探测效果。在文章最后总结了灵敏度的影响因素,并指出在进行野外工作设计时,要综合考虑灵敏度、探测深度、工作效率以及勘探成本,可以根据经验或者理论模型计算来选择适合目标探测区域的装置进行野外数据采集。随着深部找矿的需求日益增加,需要设计更大探测深度、更高效率的装置,以达到勘探目的。

DC resistivity method is one of subsurface exploration methods by study ingchange in resistivity of the underground rocks and mineral which is based on the differ- ence between rocks and minerals conductivity. In this paper, the concept, the formulas and practical meanings of sensitivity are introduced. Taking pole-pole array and dipole pole ar ray as examples, sensitivity curves of different electrode spacing are drawn, and then these sensitivity curves are compared and analyzed. Afterwards, taking simple electrical model as an example, sensitivity sections of different arrays are drawn by software, which are also compared and analyzed. The relations between sensitivity and detection depth is explored in a simple way. Sensitivity information includes the resolutions of arrays in horizontal and vertical directions, and thedetection result of subsurface media can be grasped by drawing curves and sections of sensitivity. At last, factors affecting sensitivity are summarized, and sensitivity, detection depth, efficiency, and exploration costs should be considered when designing field work. Arrays whieh is suitable for target detection areas by previous experiences and calculations of theoretical modelean be ehosen. With the increasing demand for deep prospecting, greater detection depth and more efficient arrays to achieve the purpose of exploration are needed to design.