밀양지역 납석광상 화산암질 모암에서의 원소들의 지구화학적 분산

• 영문명: Geochemical dispersion of elements in volcanic wallrocks of pyrophyllite deposits in Milyang area, Kyeongnam province
• 발행기관: 대한자원환경지질학회
• 저자명: 오대균(Dae Gyun Oh) 전효택(Hyo Taek Chon)
• 간행물 정보: 『자원환경지질』26권 3호, 337~347쪽, 전체 11쪽
• 주제분류: 자연과학 > 지질학
• 파일형태: PDF
• 발행일자: 1993.06.30

영문 초록

Mineralogical and geochemical studies on some pyrophyllite deposits in Milyang area, Kyeongnam Province (Milyang and Sungjin mine) were carried out in order to investigate dispersion patterns of chemical elements in altered volcanic wallrocks, and to interpret genetic environments of the pyrophyllite deposits. Cretaceous andesitic and tuffaceous rocks, and pyrophyllite ore specimens were collected from the dumps and drilling cores. Andesitic wallrocks were grouped as unaltered and altered rocks in the order of pyrophyllitization. Vertical dispersion patterns and relative mobilities of chemical elements in volcanic wallrocks were discussed. Geochemical environment in the Milyang area is characterized by the occurrence of boron minerals such as dumortierite coexisting with pyrophyllite ores, and tourmaline in granitic rocks. Unaltered andesitic rocks are mainly composed of plagioclase, pyroxene and hornblende, and were propylitized and saussuritized. Altered andesitic rocks are bleached and consist of quartz, sericite, pyrophyllite, kaolinite, chlorite and disseminated pyrite. Pyrophyllite ores are mainly composed of quartz, pyrophyllite, dumortierite, dissemianted pyrite and some diaspore. Enrichment of SiO₂, Al₂O₃, LOI (loss on ignition), As and Cr, and depletion of K₂O, Na₂O, CaO, MgO and total Fe are characteristic during alteration process. The REE patterns show that the pyrophyllite deposits could be originated from the continental margin volcanics. The (La/Lu)cn ratios of the pyrophyllite ores increase from 4.2~23.2 to 2.67~128.8 owing to strong acidic hydrothermal alteration. Vertical dispersion patterns of Al₂O₃, K₂O, Na₂O, CaO, MgO, Fe₂O₃ (total Fe), As, Au, Sb, Cr and Sr in the wallrocks show the location of orebodies. Particularly dispersion patterns of Al₂O₃ and Cr indicate the extension of orebodies. Anomalous distribution of Au, As and Sb in wallrocks shows potential for gold occurrence below the pyrophyllite deposits. Judging from the relative mobilities of elements in wallrocks, Al₂O₃ could be added from hydrothermal solution, and the silicified zone be formed from the excess of SiO₂.

목차

ABSTRACT

서론

지질 및 광상 개요

시료의 채취, 분류, 광물조성 및 화학분석

안산암질암 및 납석광석의 지구화학적 특성

심도에 따른 원소들의 분산양상

결론

참고문헌