Mineralogical study on wathering products of granite
Grant-in-Aid for International Scientific Research.
|Allocation Type||Single-year Grants|
|Research Institution||Hiroshima University|
KITAGAWA Ryuji Hiroshima University, Faculty of Science, Associate Professor, 理学部, 助教授 (70112167)
黄 辰淵 釜山大学, 地質学科, 副教授
SUZUKI Morihisa Hiroshima University, Faculty of Shcool Education, Professor, 学校教育学部, 教授 (10033888)
HWNAG Jin-yeon Pusan National University, College of Science, Associate Professor
|Project Period (FY)
Completed(Fiscal Year 1995)
|Keywords||Granite / Weathering / Hydrothermal / Clay vein / K-Ar age / Smectite / Kaolinite / Mica clay mineral|
The main purposes of this study are as follows :
**comparison of weathering state and degree of granitic rocks in betweenKorea and Japan.
**Mineralogical characteristics of weathering products from granitic rocks in Korea.
**Geological and mineralogical characteristic of clay veins in granitic rocks in Korea :
The field surveys were performed in three main areas, i.e. Pusan (Cretaceous granite), Kyeongju (Paleogene granite) and Soul areas (Jurassic granite). The specimens of altered granitic rocks and clay veins were collected for investigation of mineralogical characteristics of clay minerals formed in them.
2. Survey and investigation results are follows :
1) The weathering degree of Jurassic and Cretaceous granitic rocks distributed in Korea is totally very weak. The strongly decomposed granitic rocks are found at small restrict areas such as faults zone. The Paleogene granitic rock distributed in Kyeongju area is comparatively decomposed and altered. At some outcrops strongly altered granitic rocks are found.
2) Frequency of existence of clay veins in Jurassic and Cretaceous granitic rocks is very low in Korea. However many clay veins are observed in the Paleogene granitic rock (Kyeongju area).
3) As alteration products, mica clay mineral, smectite, interstratified mineral of mica and smectite, kaolinite and halloysite are identified in decomposed granitic rocks (Jurassic and Cretaceous). Main product is halloysite. However in. Paleogene granitic rock, smectite is main product.
4) The clay veins compose mainly of mica clay mineral and smectite accompanied with interstratified mineral, kaolinite and halloysite. These clay minerals were formed during hydrothermalstages of post magmaticactivities.
In Korea the Jurassic and Cretaceous granitic rocks are decomposed by weathering, on the other hand the Paleogenegranitic rocks are altered by both hydrothermaland weathering.
Research Products (6results)