溶結凝灰岩の風化による岩石物性の変化

IR Web Site

Bibliographic Information

Other Title
  • Rock property changes of welded tuff due to weathering
  • ヨウケツ ギョウカイガン ノ フウカ ニヨル ガンセキ ブッセイ ノ ヘンカ

Search this article

Abstract

Temporal changes in colour and physical properties due to weathering during 240 ka were examined using welded tuff gravel in fluvial terrace deposits with a known emergence time that were distributed in Miyazaki Plain, Japan. The time between the age of each terrace formation (8, 90, 120 and 240 ka) and the present was assumed to be the weathering period. The results of the measurements are as follows: (1) effective porosity increases as the weathering period increases; (2) the a*, b*-values of colour induces increase as the weathering period increases. These results suggest that (1) the increase in pores in gravel that occurs as the weathering period increases is caused by the dissolution of biotite; (2) iron concentration and the formation of goethite occur in older gravels. Dissolution of biotite and increasing pore volume play major roles in the weathering of welded tuff.

Journal

Keywords

Details 詳細情報について

Report a problem

Back to top