• Economic and Environmental Geology
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• v.47 no.2
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• pp.107-119
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• 2014

NMC Moland mine, which is classified as a contact replacement or skarn deposit, has been interpreted to have been formed by Daebo igneous activity which intruded into the Joseon Supergroup, because it is quite closely located to Jecheon granite. However, an alternative interpretation was recently suggested that the mine could be related with the hydrothermal fluid originated from Cretaceous granitic rocks, bringing about skarnization and Mo mineralization. Here we present an interpretation on the source granite of the mine based on the gravity exploration: the gravity anomaly, unlike the surface geology, shows that the Muamsa granite could be the related granite of the mine, because its hidden subsurface structure is expected to be more widely extended to surrounding area of the mine and deeper than the Jecheon granite.

• Proceedings of the KSEEG Conference
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• 2007.04a
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• pp.170-172
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• 2007

• Journal of the Speleological Society of Korea
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• v.7 no.8
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• pp.19-25
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• 1982

한반도에는 화산암이 각지에 널리 분포되고 있으나 특히 중남부 지역(39$^{\circ}$N이남)에 광범위하게 분포되고 있어 도처에 화강암 특유의 지형을 이루고 있다. 특히 화강암의 산출상태와 관련된 분지지형은 하나의 중요한 지형요소를 이루고 있다. 본 논문은 화강암 분포지역중에서 중위평탄면에 발달한 제천분지의 성인과 형태 및 분지내의 지형구분에 의해 지형적 성격을 구명하는 것이 주요목적이다. (중략)

• The Journal of the Petrological Society of Korea
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• v.1 no.2
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• pp.132-137
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• 1992

Review of metamorphic terms and rock names from various published articles in Korea reveals that they have often been misused and they may lead to a faulty results in the interpretations of the geologic mass. Their usage can be classified into several groups. A few simple rules are proposed for use in naming metamorphic rocks. The new rock names make by the proposed rules are listed as table with old names.

• Proceedings of the Petrological Society of Korea Conference
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• 2003.05a
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• pp.63-65
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• 2003

• Proceedings of the Petrological Society of Korea Conference
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• 2004.05a
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• pp.26-28
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• 2004

• Proceedings of the Mineralogical Society of Korea Conference
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• 2003.05a
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• pp.63-65
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• 2003

• Proceedings of the Mineralogical Society of Korea Conference
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• 2004.05a
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• pp.26-28
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• 2004

• Journal of the Korean earth science society
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• v.29 no.7
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• pp.640-644
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• 2008

A type and origin of Buyeo and Jecheon mine as the domestic leading feldspar mines are classified by using the petrological characteristics. Jecheon mine is a weathered residual mine formed by the weathering of K-feldspar megacryst bearing porphyritic granite of which forming P-T is 840-5 Kb with the igneous origin of megacryst. On the other hand, Buyeo mine is made by the metasomatic alteration of hydrothermal solution from the biotite granite intrusion. Pure albite as a main ore mineral and garnet and sericite as accessaries are observed in this mine. In addition, the mine is typically characterized by the well recrystallized mineral texture.

• Journal of the Korean earth science society
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• v.22 no.5
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• pp.405-414
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• 2001

Jecheon granite can be divided into two types; porphyritic granite (K-feldspar megacryst bearing) and medium-grained biotite granite. Porphyritic granite, host body of feldspar deposits, is 8${\sim}$11 km in diameter and about 80 $km^{2}$ in area. It mainly contains K-feldspar, plagioclase, biotite and quartz, and magnetite, zircon, sphene and apatite are accessary minerals. Enclosed minerals in K-feldspar megacryst with 3${\sim}$10 cm in diameter are hornblende, plagioclase, quartz, magnetite, apatite, sphene and zircon. Mafic enclaves mainly consisting of hornblende, plagioclase and quartz are frequently observed in porphrytic granite. Medium-grained biotite granite consists of K-feldspar, plagioclase, biotite and hornblende as main, and hematite, muscovite, apatite and zircon as accessary minerals. Core and rim An contents of plagioclase from porphyritic granite, medium biotite granite, K-feldspar megacryst, and mafic enclave are 36 and 21, 40 and 32, 37 and 32, and 43 and 36, respectively. $X_{Fe}$ values of hornblende are 0.57 at biotite granite, 0.51 at K-feldspar mehacryst and 0.45 at mafic enclave. $X_{Fe}$ values of biotite and hornblende are homogeneous without chemical zonation. K-feldspar megacryst shows end member of pure composition with exsolved thin lamellar pure albites. Characteristics of mineral compositions and petrography indicate porphyritic granite is igneous origin and medium-grained biotite granite comes from the same source of magma; biotite granite is initiated to solidly and from residual melt porphyritic granite can be formed. Possibly K-feldspar megacrysts are formde under H$_{2}$O undersaturation condition and near K-feldspar solidus curve temperature; growth rate is faster than nucleation rate. Mafic enclaves are thought to be mingled mafic magma in felsic magma, which is formed from compositional stratigraphy. Estimated equilibrium temperature and pressure for medium-grained biotite granite are about $800^{\circ}C$ and 4.83${\sim}$5.27 Kb, respectively.