한반도 남서부 남원 일대에 분포하는 A형 대강 화강암의 암석학,지화학 및 지구조적 의미

• 발행기관: 대한자원환경지질학회
• 저자명: 김용준 조등룡 이창신
• 간행물 정보: 『자원환경지질』31권 5호, 399~413쪽, 전체 15쪽
• 주제분류: 자연과학 > 지질학
• 파일형태: PDF
• 발행일자: 1998.10.30

영문 초록

Daegang granite is located around the Namwon-gun, Cheolabuk-do, and is an elongate stock (80㎢) in the NNE-SSW direction. Daegang granite has the very same mineralogical and geochemical characteristics as those of the typical A-type granites; (1) it is a one feldspar hypersolves granite, and is classified as an alkali feldspar granite in the IUGS scheme , (2) has small amounts of Fe-rich biotite (annite) and alkali amphibole (ribeckite) that are late in the crystallization sequence of the granitic magma, (3) always contains opaque oxides, fluorite and zircon, (4) shows high and quite homogeneous SiO₂content (mostly 72∼77 wt.%) and (Na₂O+K₂O)/Al₂O₃ratio (0.90∼0.98), (5) contains high Ga, 10000*Ga/Al, K₂O+Na₂O, (K₂O+Ma₂O)/CaO, K₂O/MgO, FeO/MgO, agpaitic index, Zr, Nb, Ce, Y, Zn value or ratio that resemble to those of the Australian A-type granites (Whalen et al., 1987), and (6) has enriched LREE and HREE that show flat variation pattern with slightly depleted in HREE and profround Eu anomalies (Eu/Eu=0.04∼0.14). In the tectonic discrimination diagrams of Pearce et al. (1984) and Eby (1992), Eaegang granite is classified as a within plate granite and A₂-type.

키워드

남원 대보화강암 트라아스기 쥬라기 마그마호화강암 충돌성화강암 불국사화강암 유색광물 A형화강암