Abstract
Brown soil was collected from the landslide area, Mie-mura, Nishikano-gun, Nagasaki Prefecture and was studied by X-ray, thermal, infrared absorption and electron microscope method.
It was determined to consist of, beside quartz, feldspar and gibbsite, such clay minerals as illite, Alvermiculite, random mixed-layer illite Al-vermiculite and kaoline.
It may be considered that these clay minerals were largely produced by the weathering of thin layer of biotite developed along the schistosity of spotted graphite sericite schist and promoted the landslide phenomenon along the schistosity of the above-rock.
