Identification method of neutral volcanic-andesite

Abstract

The invention relates to an identification method of neutral volcanic-andesite. The identification method comprises the following steps: finding a to-be-detected plagioclase from a rock slice under anorthogonal polarizing microscope; respectively testing extinction angles of two groups of bicrystal monomers of the plagioclase to be tested; if the difference between extinction angles of the two groups of bicrystal monomers is less than 5 degrees, considering that the section of the plagioclase to be tested is the section of the inverted-T (010) bicrystal junction surface, and taking the average value of the extinction angles of the two groups of bicrystal monomers, namely the maximum extinction angle phi max of the inverted-T (010) section; if the difference between the extinction angles obtained in the two times is greater than 5 degrees, taking the average value of the extinction angles of the two groups of bicrystal monomers as a visual extinction angle phi '; and at the moment, ifthe apparent extinction angle phi' of the meso-clinic stone is smaller than 24 and the bicrystal width c is smaller than 0.029777 mm when the section is beveled into the bicrystal surface, the meso-clinic stone can be determined as the meso-clinic stone, and the rock sample is the neutral volcanic-andesite. Neutral volcanic rock-andesite can be quickly and accurately distinguished from basic volcanic rock-basalt and transition rock-basaltic rock-basaltic rock, and the identification accuracy is high.

Description

technical field [0001] The invention belongs to the field of identification of rock types, and relates to an identification method of neutral volcanic rock-andesite, in particular to a method for identifying neutral volcanic rock-andesite under an orthogonal polarizing microscope. Background technique [0002] The information disclosed in this background section is only intended to increase the understanding of the general background of the present invention, and is not necessarily taken as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. [0003] The identification method of neutral volcanic rock-andesite currently used in China: GB / T 17412.1-1998 "Rock Classification and Naming Scheme for Igneous Rocks and Rock Classification and Naming Scheme" - issued by the State Bureau of Quality and Technical Supervision and SY / T 5368-2000 "Identification of Rock Thin Sections" —Based on the People's ...

AI Technical Summary

Problems solved by technology

The first condition of these methods is that the selected plagioclase crystal to be tested must be a directional cut surface, and a series of optical data such as its refractive index, birefringence, and optical axis angle must be accurately measured, and the relevant identification charts are used for identification. , but also need to cooperate with other means, such as oil immersion method, rotating table to measure the optical axis angle (2V), etc., which makes the identification operation complicated and cumbersome

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