石英砂扫描电镜在漓江“泥砾”成因中的应用

本文根据扫描电镜对从漓江河谷钻孔中的泥砾层取得的481粒石英砂表面形态特证研究结果:石英砂多数颗粒保持棱角状外形并遭受不同程度的磨蚀,具阶状贝壳断口,平直或弧形刮削面和多向擦痕,沿解理面破碎呈“V”字形沟和撞击碟形坑,以及微溶蚀孔、隙、蜂窝状溶孔群和SiO_2再沉积等表面形态结构特征。认为它是在第四纪古地理湿热气候条件下泥石流沉积的产物,物源可能来自境内或周边的泥盆系砂岩和境外的花岗岩。

APLICATION OF SEM STUDY ON QUARTZ SANDS TO THE RESEARCH OF THE ORIGIN OF THE MUD GRAVEL OF THE LI RIVER, GUILIN, CHINA

Based on the study of 481 grains of quartz sands from the mud gravel of the Li River valley by SEM, results of the surface characteristics of quartz sand are obtained. The quartz sands are angle-shaped and suffer from abrasion to different degree and show conchoidal fractures, straight or arc surfaces and irregular scratches. V-shaped ditches along the cleave, shock dish pit, microcracks and pore space and honeycomed pore group of solution and resedimentary SiO2 can be observed on the surfaces of the quartz sands. All above surface characteristics show that the quartz sands are the products of mud-debris flow deposits under the humid-scorching climate in the Quaternary Period and may be derived from the Devonian sandstones and the granite in the surrounding area.