광화유체의 비등과 희석에 의한 통영 천열수계 Au-Ag-Te 광화작용에 대한 반응경로 모델링

박맹언,성규열,Laurence P. James 대한자원환경지질학회 2001 자원환경지질 Vol.34 No.6

통영광산은 천열수광상으로서 능망간석, 백운모, 일라이트, 황철석, 방연석, 황동석, 섬아연석, 아칸다이트 및 헤사이트 등의 광물을 수반하는 초기의 광석광물 침전시기와 후기의 맥석광물 침전시기로 구분된다. 초기는 반복적인 대상구조를 띠고, 황화광물이 침전된 시기로서 텔루리움 광물과 함께 엘렉트림이 산출된다. 후기에는 주로 탄산염 광물과 천금속광물이 침전되었다. 통영 열수계에서 광화단계에 따른 상이한 열수유체의 변천과정을 구체적으로 규명하기 위하여 프로그램 CHILLER를 이용한 수치모델링이 실시되었다 반응경로 모델링은 280℃에서 모암인 안산암과의 반응을 비롯하여, 260℃에서 120℃까지의 단순한 등압 냉각, 비등과 지하수의 혼입에 따른 희석 및 압력과 온도가 감소되는 조건에서 수행하였다. 모델링 결과 초기 광화유체는 산성용액(pH=5.7)으로 상대적으로 높은 염농도와 금속원소 함량이 높다. 광화유체 내의 금의 함량은 열수계의 천금속원소 총량과 황화물의 활동도에 의해 지배된다. 통영 천열수계에서의 광화작용은천부에서 일어난 광화유체의 비등과 이에 수반된 가열된 지하수의 혼입에 의한 반응경로를 반영하며, 현미경에서 관찰된 광물공생 특성과 모델링에 의한 침전광물의 조합 및 엘렉트림의 화학조성 등에서 동일한 경향을 나타랜다. 이러한 유사성은 Te 함유하는 천열수 금 ·은광상이 열수계에서의 비등과 유체혼합(희석)에 의해 생성되었음을 지시한다 반응경로 모델링 연구는 광상성인을 이해하는 중요한 수단이며, 유사한 지질환경에서의 광상탐사에 유용한 자료로 활용될 것으로 생각된다. At the Tongyeong mine, quartz, ihodochrosite (kutnahorite), muscoyite, illite, pyrite, galena, chalcopyrite, sphalerite, acanthite, and hessite are the principal vein minerals. They were deposited under epithermal conditions in two stages. Ore mineral assemblages and associated gangue phases in stage can be clearly diyided into two general associations: an early cycle (band) that appeared with inooduction of most of the sulfides and electrum, and a later cycle in which base metaland carbonate-bearing assemblages (mostly rhodochrosite) became dominant. Tellurides and some electrum occur assmall rounded grains within subhedral-to euhedral pyrite or anhedral galena in stagell. Sulfide mineralization is zonedfrom pyrite to galena and sphalerite. W3 have used computer modeling to simulate formation of four stages of vein gen-esis. The reaction of a single fluid with andesite host rock at 280℃, isobaric cooling of a single fluid from 260℃ to 120℃, and boiling and mixing of a fluid with both decreasing pressure and temperature were studied using the CHILLER program. Calculations show that the precipitation of alteration minerals is due to fluid-andesite interaction as temperature drops. Speciation calculations confirm that the hydrothermal fluids with moderately high salinities and pH 5.7 (acid), werecapable of transporting significant quantities of base metals. The abundance of gold in fluid depends critically on the ratioof total base metals and iron to sulfide in the aqueous phase because gold is Oansported as an Au(HS)₂- complex, which is sensitive to sulfide activity. Modeling results for Tongyeong mineralization show soong influence of shallow hydro-genic processes such as boiling and fluid mixing. The Yariable banding in stagell mineralization is best explained by mul-tible boilings of hydrothermal fluid followed by lateral mixing of the fluid with overlying diluted, steam-heated ground water. The degree of similarity of calculated mineral assemblages and observed electrum composition and field relationships shows the utility of the numerical simulation method in identifying chemical processes that accompany boiling and mixing in Te-bearing Au-Ag system. This has been applied in models to narrow the search area for epithermal ores,.

가상체액성분에 대한 광물약의 반응 모델링 : 위액-주사반응과 수은착물의 농도

박맹언,김선옥 대한지질학회 1998 대한지질학회 학술대회 Vol.1998 No.

계명산층내 알칼리 화강암 기원의 Nb-Y 광화작용에 수반되는 퍼구소나이트의 지구화학 및 산출특성 연구

박맹언,김근수,최인식,Park, Maeng-Eon,Kim, Gun-Soo,Choi, In-Sik 대한자원환경지질학회 1997 자원환경지질 Vol.30 No.5

Some RE (Zr, Nb, REE) ore deposits are located in the middle part of the Korean peninsula. Geotectonically, the RE ore deposits situated on the Kyemyeongsan Formation of northern margin of the Okcheon geosynclinal belt and in the transitional zone between Kyeonggi massif and Okcheon belt. The rare metal deposits distributed in Kyemyeongsan Formation which consists of schist and alkaline granite. The alkali granite has suffered extensive post-magmatic metasomatism and hydrothermal processes. The ore contains mainly Ce-La, Ta-Nb, Y, Y-Nb, Ti-Nb-(U), Nd-Th group minerals. Fergusonite, one of Nb-Y rich REE minerals belonging to the A-B oxides, is most common mineral in the rare metal deposits. The fergusonite bearing rocks may be devided into four types by occurrence features and mineral association, that is, zircon type, allanite vein, feldspar type, and fluorite type. Fergusonites show wide variations in optical properties, due to part of differences in their chemical composition (depending on the types), but also the degree of crystalinity of the individual specimens. Fergusonite metamicts enclosed in biotite are generally surrounded by well developed pleochroic haloes. Usually, fergusonite is accompanied with zircon and other REE-bearing minerals. Petrographical and chemical data are presented for fergusonites which collected different types. $Nb_2O_3$ and $Y_2O_3$ contents range from 48.51 to 53.01 wt.% and 29.18 to 42.02 wt.% respectively. Also, $ThO_2$, (1.83~6.93), $UO_2$, (0.17~2.84), ${\sum}RE_2O_3$ (except to Y) (1.11~8.73), and $TiO_2$, (0.19~1.19 wt.%) contents show variational compositions according to fergusonite types. The ${\sum}RE_2O_3$ of fergusonites are positive relation with $Y_2O_3$ and negative relaton with $ThO_2$ and $({\sum}{RE_2O_3}-{Y_2O_3})$. The $Nb_2O_3$ is sightly negative relation with $Ta_2O_3$. Back-scattered electron microscope images (BEI) of fergusonite show the mineral composition and textural feature is very complicated. The variation of Nb, Th and REE content of fergusonite and the modes of occurrence of mineral, suggests that REE may have been mobilized during the circulation of hydrothermal fluids related to contact metamorphism (metasomatism). The chemical variation of the fergusonites with occurrences and mineral association can be related to metasomatism of alkaline fluid was probably the dominant ore-forming process in Chungju district.

광포만 집수유역내에 분포하는 점토광물의 성인에 관한 연구

박맹언,김희준,김대철,송용선,백인성,정상용,송시태 한국수산학회 1988 한국수산과학회지 Vol.21 No.4

광포만 집수유역에 분포된 점토광상들은 회장암질 암체에 제한되어 산출된다. 광체의 최상부에서는 로몬타이트와 메타-할로이사이트가 가장 우세하게 발달되고 철산화물이 수반되며, 하부에서는 녹니석과 할로이사이트가 우세하게 산출된다. 주점토층 아래에 놓인 일부 회장암질 암류는 열수맥을 따라 석영, 견운모, 녹니석, 황철석 및 몬모릴로나이트 등으로 심하게 변질되어 있다. 열수와 강우를 각각 100℃와 25℃에서 회장암질암과 반응시킨 다성분 평형반응계산에 의해 열수변질과 풍화변질 기원의 가설들을 시험해본 결과 강우와의 반응결과가 야외에서 산출되는 점토광물군과 보다 유사함을 보인다. 이는 본역 점토광상의 주성인이 풍화변질작용임을 나타낸다. Clay deposits in the vicinity of the Gwangpo Bay, southern coast of Korea, occur restrictively in anorthositic masses. Laumontite and meta-halloysite are the predominant clay minerals with iron oxides at the uppermost surface. Chlorite and halloysite occur in deeper zone. Beneath the main clap horizon, but not above, some anorthositic rocks are pervasively altered to quartz, sericite, chlorite, pyrite and montmorillonite along the hydrothermal channels. The hypotheses of hydrothermal and weathering origins of the clay minerals are tested by multi-component equilibrium calculations of the reactions of modified hydrothermal water and rain water with anorthositic rocks at 100℃ and 25℃, respectively. The calculated mineralogy from the reaction with rain water resembles natural mineral assemblage except for abundance in laumontite. The result implies that the weathering process is the main machanism of the formation of clay deposits in the area.

충주지역 희유원소광상에서 산출되는 갈렴석의 지구화학적특성

박맹언,김근수,최인식,Park, Maeng-Eon,Kim, Gun-Soo,Choi, In-Sik 대한자원환경지질학회 1996 자원환경지질 Vol.29 No.5

Rare metal (Nb-Zr-REE) ore deposits are located in the Chungju area. Geotectonically, the rare metal ore deposits are situated in the transitional zone between Kyeonggi massif and Okcheon belt. The rare metal deposits are distributed in Kyemyeongsan Formation which consist of schist and alkaline igneous rocks. Alkali granite has suffered extensive post-magmatic metasomatism and hydrothermal processes. The ore contains mainly Ce-La, Ta-Nb, Y, Y-Nd, Nd-Th group minerals. More than 15 RE and REE minerals are found in the ore deposits. Allanite, one of the Ce-La rich REE minerals belonging to the epidote group, is the most common mineral in the studied area. The allanite- bearing rocks may be devided into seven types by features of occurrence and mineral associations; zircon type (ZT), allanite-vein type (AT), feldspar type (KT), fluorite type (FT), quartz-mica type (QT), iron-oxide type (MT), and amphibole type (HT). The allanite veins (AT) and zircon rich rocks (ZT) contain the highest total REE contents. Differences in REE abundance can be interpreted in terms of varying portions of magmatic hydrothermal fluid. Petrographical and chemical data are presented for allanites which were collected from different types. The allanites show wide variations in optical properties, due in part to differences in their chemical composition (depending on the types) and to the degree of crystallinity of the individual specimens. Allanite metamicts in biotite are generally surrounded by well developed pleochroic haloes. Usually, allanite is accompanied by zircon and other REE-bearing minerals. CaO and total REE contents $({\sum}RE_2O_3)$ range from 9.29 to 18.79% and 11.66 to 26.31%, respectively. Also, SiO, (28.87~32.61%), $Al_2O_3$ (8.30~16.88%), and $Fc_2O_3$ (16.74~24.38%) contents show varying contents from type to type. The ${\sum}RE_2O_3$ of allanite has positive relationships with $Fe_2O_3$ and negative relaton with CaO, $SiO_2$, and $Al_2O_3$ Backscattered electron microscope images (BEl) of allanite shows that the its mineral composition and texture is very complex. The allanite-bearing hosts show distinct light REE enrichment with strong negative Eu anomaly except for HI. The HT has an almost flat REE distribution pattern with a small negative Eu anomaly. The chemical variation of the allanites with occurrences and mineral association can be related to condition of temperature and oxidation states in precipitation environment.

충주지역 고생대 광화작용의 특성

박맹언,김근수 대한지질학회 1995 대한지질학회 학술대회 Vol.1995 No.

충주지역 희토류 광상의 성인: 산출상태와 지화학적 특성

박맹언,김근수,Park, Maeng-Eon,Kim, Gun-Soo 대한자원환경지질학회 1995 자원환경지질 Vol.28 No.6

Some REE ore deposits are located in the middle part the of Korean peninsula. Geotectonically, the REE ore deposits situated on the Kyemyeongsan Formation of northern margin of the Okcheon geosynclinal belt and in the transitional zone between Kyeonggi massif and the Okcheon belt, with a deep-seated fracture separating the two tectonic units. The Kyemyeongsan Formation are different in lithology and metamorphic grade from the Gyeonggi massif and the Okcheon super group. The sequence of Kyemyeongsan Formation is dominantly composed of acidic metavolcanic and volcaniclastic rocks associated with alkaline igneous rocks which are related to volcano-plutonism. The REE ore deposits contain mainly Ce-La, Ta-Nb, Y, Y-Nd and Nd-Th group minerals. More than 15 RE and REE minerals have been found in the deposits, such as allanite, fergusonite, thorite bestnaesite, euxenite, polyclase, monazite, columbite, (Nb)-rutile, okanoganite, sphene, zircon, illmenite and some other unknown minerals. According to the characteristics of the mineral association, the REE ore deposits may be divided into 4 ore types; Zircon-REE, allanite-REE, feldspar-REE and fluorite-REE type. The Sm-Nd isochron age of the REE ore is 330 Ma, and the Sm-Nd model age is 1.11 Ga with ${\varepsilon}_{Nd(t)}$ being - 2.9. This data suggest that the REE ore deposit was formed in the early Carboniferous, and the ore-forming material came from the mantle. The REE ores show distinct light REE enrichment with strong negative Eu anomaly. The REE patterns of schistose rocks from Kyemyeongsan Formation are similar to felsic volcanics from rifts or back arc basins in or near continental crust. The genesis of the REE ore deposit is quite complicated. Different geologic processes are displayed in the studied area; sedimentation, volcanic activity, metamorphism and hydrothermal replacement. Alkali granite has suffered extensive post-magmatic metasomatism of a high temperature to produce alkali metasomatites. Geochemical charateristics show that metasomatism of alkaline fluid was probably the dominant ore-forming process in Chungju district.

가상체액에 대한 광물약의 반응 특성 모델링 ; 위액-주사 반응과 수은착물의 농도

박맹언 부경대학교 기초과학연구소 1999 부경대 기초과학연구논문집 Vol.2 No.-

H/F Variation in Wolframites According to Depth and Temperature of Mineralization at Ssangjeon, Weolag, Cheongyang and Sannae Mines, Korea

박맹언,Park, Maeng-Eon The Korean Society of Economic and Environmental G 1993 자원환경지질 Vol.26 No.3

본 논문은 심도별 시료 채취가 가능한 국내 주요 함중석 열수석영맥 광상 (쌍전, 월악, 청양, 산내광산)에서 산출되는 철 망간중석과 동일맥 중 공생단계에 있어서 밀접하게 수반되는 같은 광화시기의 석영을 대상으로 유체포유물 온도, 철 망간중석에서의 H/F값 및 광화작용의 섬도와의 상관관계를 밝히기 위해서 시도 되었다. 연구대상 함중석 열수석영맥광상에서 철 망간중석의 H/F값은 생성온도와 광화작용의 심도에 따라 특정적인 상관관계를 보여준다. 윌악, 청양 및 산내광산에서 산출되는 철 망간중석의 H/F값은 광화온도가 높을수록 광화심도가 깊을수록 증가된다. 이는 광화용액의 pH값이 냉각과 모암과의 반응에 따라 감소되었음을 시사한다. 쌍전광산의 경우 생성온도가 높아짐에 따라서 상대적으로 제한된 범위내에서 H/F값이 증가되나 심도에 따라서는 상기 광산과는 상반된 결과를 나타낸다. 이러한 결과는 알카리장석과 견운모등의 침전에 따른 pH값의 증가를 유도한 물리 화학적 환경이 조성되었음을 의미한다. 본 연구에서 밝혀진 함중석-휘수연 열수 석영맥에서 산출되는 철 망간중석의 심도에 따른 생성온도와 H/F값의 특성은 유사한 지질환경의 물리화학적 조선(동일한 공생단계)이 형성되면 지질온도계로서의 활용이 가능하며 H/F값은 열수석영맥에서 산출되는 철 망간중석광의 심도 탐광시 고려되어야 할 요건으로 심도추정 및 탐사지침으로 활용할 수 있을 것으로 사료된다. The variation of H/F coefficient (Hubnerite/Feberite coefficient) and the temperature of formation with depth have been studied for the hydrothermal tungsten-quartz veins from Ssangjeon, Weolag, Cheongyang, and Sannae mines. All samples were selected at the same paragenetic stage and mineral assemblege according to depth. The studied mines provide an opportunity to examine and regional variations in wolframite composition in different provinces. The formation temperature is linearly related to the depth. At the Weolag, Cheongyang and Sannae mines, the H/F ratio of wolframite and filling temperatures of fluid inclusions in quartz show a general tendency to decrease at shallow levels, in spite of different geological settings. This implies the pH of fluid will decrease vertically with falling temperature and the high H/F ratio of wolframite in deep zone result in an increase of pH with depth. The Ssangjeon mine exhibits a tendency to increase slightly upwards at shallow level. This implies a different geochemical environment (high pH environment) for the Ssangjeon mine, as compared to the other three mines. The H/F coefficient pattern suggests that it is a useful geothermometer for vein-type tungsten deposits in Korea. The H/F coefficient as an indication of depth should be examined for use in exploration.

유문암-열수 반응과 유광 견운모 광상의 성인

박맹언,최인식,김진섭,Park, Maeng-Eon,Choi, In-Sik,Kim, Jin-Sup 대한자원환경지질학회 1992 자원환경지질 Vol.25 No.3

The hydrothermal alteration is evaluated using multicomponent equilibrium calculations with the program CHILLER for the reactions between hydrothermal water and rhyolite at the temperature of $300^{\circ}C$ and pressure of 500 bars. The chemical-reaction model on the depositional processes of the sericitite confirms that the hydrothermal water-rock interaction(hydrothermal alteration) is the main mechanism of the sericitite formation. The principal change in the aqueous phase during the reaction is the pH increase. Overall trends for the major species are the increase in total molalities of K, Ca, $SiO_2$, Al, Mg, Fe, Na, and sulfide in solid phase with hydrothermal water-rhyolite reaction and the decrease of them in aqeous solution by precipitation of hydrothermal products. Quartz and sericite are the first minerals to form. The sequence of minerals to precipitate following them is chlorite, epidote, pyrite and microcline as water/rock ratio decreases. Although calculated results cannot duplicate the complexities of natural hydrothermal alteration, the calculation provides thermodynamic constraints on the natural process. The calculation results resemble those of experimental studies. Sericitite forms where pH decreases and water/rock ratio increases.