볼음도 자철광상의 초염기성-염기성암과 티타늄자철광석의 광물 및 지구화학적 연구

• 발행기관: 대한자원환경지질학회
• 저자명: 김규한 황수진
• 간행물 정보: 『자원환경지질』33권 1호, 1~18쪽, 전체 18쪽
• 주제분류: 자연과학 > 지질학
• 파일형태: PDF
• 발행일자: 2000.02.28

영문 초록

Lens shaped and stratiform titanomagnetite orebodies in the Boreumdo iron mine are closely associated with amphibolite which intruded into Precambrian metasediments. Mineralogical and petrochemical analyses of amphilbolite and titanomagnetite ores were carried out in order to interpret the origin of amphilbolite and the genesis of titanomagnetite ore deposits. Amphibolites belong to orthoamphilbolite interms of Niggli value and mineralogy, and are characterized by the occurrence of relict olivine. The amphilbolites responsible for titanomagnetite mineralization have extremely high content of TiO₂, ranging from 2.12 to 4.59 wt.% with the average value of 3.43 wt.%. Amphibole minerals in amphibolites are consist mainly of calcic amphiboles such as hornblende, ferroan pargasitic hornblende and tremolite. Most plagioclases belong to andesine (An?). The metamorphic temperature and geobarometric pressure which are calculated by the calcic amphibole-plagioclase geothermometer and calcic amphilbole geobarometer are estimated to be 537℃∼579℃(avg. 555℃) and 2.9∼6.6 kbar (avg. 4.5 kbars), respectively. It shows a typical amphibolite facies. Based on the mineral chemistry and petrochemisty of amphibolites and iron ores which are composed mainly of titanomagnetite and ilmenite in the Boreumdo iron mine, the titaniferous oxide melts could be immiscibly separatd from the titaniferous ultrabasic magma. The genesis of the Boreumdo titanomagnetite ore deposits are analogous to the Soyeonpyeongdo and Yonchon iron ore deposits in terms of their mineralogy, mineral chemistry and geologic setting.

키워드

자철광상 볼음도 철광상 염기성암 각섬암 미량원소 희토류원소