The Terahertz Characterization Of Rock Geological Age And Type

Rock is a stable body composed of various minerals.It is one of the material compositions of the earth's crust and the main component of the earth's lithosphere.It is of great significance to distinguish the rock geological age and lithology type for the exploration and development of resources.In this paper,the terahertz time-domain spectroscopy system was used to distinguish and characterize the rock relative geologic age and the type of rock lithology.Starting from the composition and content of rock,polarizing microscopy and statistical methods are used to assist the analysis.Finally,the mineral content in the mixed system is quantitatively analyzed,and the terahertz characterization method for the relative geological age of rocks is preliminarily established.The main contents and conclusions of this paper are as follows.(1)Terahertz time-domain spectroscopy was used to detect natural rock samples with the same area and lithology.Combining with polarizing microscope and principal component analysis method,it is found that the relative geological age of rocks can be analyzed by using terahertz optical parameters(absorption coefficient,refractive index)and principal component score values,and the terahertz characterization method of relative geological age of rocks is preliminarily established.(2)Terahertz time-domain spectroscopy is used to detect natural rock samples of different lithologies.The content of the sample components is identified by polarized light microscopy.Combined with cluster analysis and principal component analysis,the lithology types of rocks were effectively distinguished.At the same time,the relationship models between terahertz optical parameters and content of rock components were established,which lays a foundation for the terahertz technology in the quantitative analysis of rock components.(3)Taking the composition of sandstone minerals(quartz,potassium feldspar and biotite)as the standard,three minerals are mixed in different kinds and proportions,and the mixed samples were detected by terahertz time-domain spectroscopy system.Basedon the analysis of terahertz spectral characteristics of single mineral,the relationship between the ratio of single minerals in two-and three-component mixtures and the terahertz optical parameters(absorption coefficient)is explored,and the mineral content in the mixed samples is quantitatively characterized.