한반도 남서부 영암의 화강암 구릉대 적색토의 화학적 풍화 특색 = Chemical Weathering Characteristics of Red Saprolites at Granitic Hills in Yeongam, Southwestern Korea

국문 초록 (Abstract)

한반도 남서부에 위치한 영암 일대의 화강암 구릉대에는 적색의 지표피복물들이 일반화되어 나타나고 있으며, 이를 고온다습한 고기후의 산물로써 성대토 개념으로 간주되어 왔다. CIA와 A-CN-K, A-CNK-FM 도식을 이용하여 이들 적색의 풍화층이 지니는 화학적 풍화 특색을 살펴본 결과, 모암에서 사장석이 완전 풍화에 준하는 수준의 강한 화학적 풍화가 일어남으로써 사질의 풍화층이 형성되었고, 풍화층이 형성된 이후로는 칼륨 장석의 용탈에 의해 풍화층의 화학적 변화가 일어나고 있는 상태이다. 그러나 일라이트와 같은 일차 광물의 수준을 넘어서지 못한 상태에 있으며, 라테라이트 단면에서 나타나는 카올리나이트와 같은 2차 광물로의 화학적 풍화는 진전되지 못한 상태이다. 화학적 풍화의 결과로서 알칼리 성분들은 용탈에 의해 함량이 낮아진 상태이지만, 철분과 마그네슘 같은 유색 광물들은 상대적으로 미약한 용탈이 발생하여 풍화층의 적색화가 이루어지고 있는 것으로 판단된다.

다국어 초록 (Multilingual Abstract)

Red saprolites are appeared in granitic hills in Yeongam, Southern Korean Peninsula. These red saprolites were analyzed for their geochemistry, including CIA, A-CN-K and A-CNK-FM ternary plots, to understand the chemical weathering trend and rubefaction of the saprolites. These saprolites were compared with laterite profiles in Cameroon formed under humid tropical conditions. The red saprolites in Yeongam show commonly massive loss of CaO, Na₂O, but K₂O is being slow. The red saprolites in Yeongam relative to laterite and kaolinite profiles of Cameroon and Spain show weak chemical alteration owing to slow removal of K₂O, but high mafic constituents, Fe₂O₃ and MgO, for most of the samples. In the saprolites of Yeongam, mafic oxides become enriched because of the fast and massive removal of alkali constituents, such as CaO, Na₂O and K₂O, relative to other elements, resulting in rubefaction of the saprolites. It is found that the rubefaction of the saprolites is not necessarily proportional to chemical weathering intensity.

목차 (Table of Contents)

• Abstract
• 요약
• 1. 서론
• 2. 연구지역의 지형과 분석 방법
• 3. 지화학적 분석 결과
• 4. 토의
• 5. 결론
• 참고문헌

참고문헌 (Reference)

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