龙门山构造带北段岩石物性研究

The physical properties study of the northern section of iongmenshan tectonic belt

在岩矿物性的研究中,为了能有效顺利的开展工作,往往需要了解工作区域内岩石矿物之间的物性差异,包括岩石之间的电性差异、磁性差异、密度差异等。对岩石物理性质的研究不仅是物探工作中地球物理场及地质解译的基础,也是对岩石形成时的地质条件、气候条件等的反映。此次研究发现,龙门山构造带北段岩石物理性质方面有较强的差异,尤其是电阻率、磁化率、密度差异较大,可以进行电法、磁法、重力等方法勘探。了解了该区域的物性特征,可以辅助指导该区域的电法、电磁法、重磁法等勘探方法。在对岩石物性数据采集后,进行统计分析和相关分析,结合研究区的地质特征,分析研究区岩石物性分布情况以及岩石物性的主要影响因素。选择相关剖面与音频大地电磁测深(AMT)结果对比,发现两者近地表电阻率特征具有良好的对应关系,这也验证了岩石物性测试结果的准确性,这为在该区以后的物探测量及地质解释等方面能提供更好的依据。

Before starting many geological work,in order to carry out the work effectively and successfully,we often need to understand the physical differences of rocks and minerals in study area,including the electrical differences、magnetic differences and density differences.The study of physical properties is not only the essential foundation of geophysical field work and geological interpretation,but also reflects geological and weather conditions in which they are formed.This study find that the physical properties of the north section of Longmen mountain tectonic belt have big differences,especially the resistivity、magnetic susceptibility and density.Electrical method,magnetic method,and gravity method can be carried out in the study area.We find the characteristic of physical properties in study area.It can guide electrical method,electromagnetic method,gravity and magnetic exploration method.After acquisition physical data of rocks,combing the geological characteristics of the study area and the results of statistical and correlation analysis to analyze the physical distributions of rocks and the main influencing factors of the study area.Choosing relevant profile and comparing with the result of Audio-frequency Magneto telluric,finding that the near-surface resistivity features have a good correspondence.It also certificates the accuracy of the AMT test results.It can provide better overview for geophysical survey and geological interpretation in the study area.