• 자원환경지질
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• 제26권2호
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• pp.155-166
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• 1993

Gold contents with major and trace elements have been determined in 67 fresh igneous and altered wall rocks in the acid-sulfate alteration zone of the Ogmaesan-Seongsan pyrophyllite deposits in the Haenam area of the south-western part of Korean peninsula. The results are as follows; (1) Li contents have a tendency to show high value in dickite and altered rocks with dickite, while As, Mo and Sb contents have tendencies to show high values in alunite vein and silicified zone. F contents are higher in the altered rocks compared to fresh rocks. (2) Gold contents are enriched in alunite vein and silicified zone of the Seongsan deposit, but depleted in dickite and altered rock with dickite. Gold contents are especially concentrated in fault or conjunction area of two faults. (3) Gold contents are higher values in the mineral assemblages of alunite-quartz-pyrite and alteration zone of the Seongsan deposit among the studied deposits. (4) Gold contents in samples of silicified zones tend to show positive correlations with Ag, As, Co, Hg, Sb and V content, but negative correlations with Y and Zr contents, while on the other gold contents of silicified tuffs tend to show positive correlations with Hg and Sb contents. Therefore it is important to survey alunite vein and silicified zone at the conjunction of faults, and to analyze pathfinder elements such as Ag, As, Hg and Sb for geological and geochemical exploration of gold in the studied deposits.

• 지구물리와물리탐사
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• 제7권1호
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• pp.99-104
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• 2004

A combination of drilling, geophysical well logging, and electrical soundings was performed to evaluate seawater intrusion in Baeksu-eup, Youngkwang-gun, Korea. The survey area extends for over 24 $km^2$. To delineate the extent of seawater intrusion, 60 vertical electrical soundings (VES) have been carried out. Twelve wells were also drilled for the collection of hydrogeological, geochemical, and geophysical well logging data, to delineate the degree and vertical extent of seawater intrusion. To map the spatial distribution of seawater in this coastal aquifer, geophysical data and hydrogeochemical results were used, and the relation between the resistivity of groundwater and equivalent NaCl concentration was found. Layer parameters derived from VES data, various in-situ physical properties from geophysical well logging, and the estimated equivalent NaCl concentration were very useful for quantitative evaluation of seawater intrusion. Our approach for evaluating seawater intrusion can be considered a valuable attempt at enhancing the use of geophysical data.

• Spatial Information Research
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• 제19권4호
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• pp.81-89
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• 2011

이 논문에서는 공간적으로 소수의 지점에서 획득된 현장 조사 자료의 공간 보간 과정에 범주형 자료를 결합하는 다변량 크리깅 기법을 제안하고자 한다. 범주형 자료를 결합하는 과정에서 기존 범주형 자료의 속성별로 대푯값을 할당하는 단일 지역 평균 기반의 단순 크리깅 방식 대신에, 영역-점 변환 크리깅을 이용하여 원하는 해상도로 상세화시킨 추정값을 가변적 지역 평균으로 이용하였다. 지화학 원소 구리의 공간 보간에 지질도를 이용하는 사례연구를 통해 제안 기법을 예시하였다. 교차 검증 결과, 제안 기법이 단변량 정규 크리깅과 기존 단일 지역 평균 기반의 단순 크리깅 기법에 비해 각각 15%와 25%의 예측 능력의 향상을 나타내었다. 따라서 범주형 자료를 부가 자료로 이용하는 공간 보간에 이 논문에서 제안한 기법이 효율적으로 적용될 수 있을 것으로 기대된다.

• Ocean and Polar Research
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• 제36권2호
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• pp.179-187
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• 2014

Directly searching for undiscovered hydrothermal vent sites is inefficient due to the practical difficulty of comprehensively imaging vent fields. Thus, most searches for hydrothermal vent sites rely on the detection of hydrothermal plumes from water column observation. Detecting and measuring the hydrothermal plumes are the most efficient way to infer the presence and distribution of hydrothermal vents. Both the array of vertical casting and lateral towing are the most common methods to discover hydrothermal plumes. In this study, we compared results of cast and tow-yo operations along the same section of a spreading center with a distance of 20.5 km in the North Fiji Basin for mapping hydrothermal plumes. Operation of CTD tow-yo provides a detailed pattern of plumes which enable us to locate the hydrothermal vents. On the other hand, identification of hydrothermal activity can be determined effectively by CTD cast with additional analysis of geochemical tracers. Reduction in the operating time is another advantage of CTD cast operation, especially for regional-scale survey. Our results show that the combination of CTD cast and tow-yo would improve the efficiency of the hydrothermal plume survey to locate new hydrothermal vent sites.

• 지질공학
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• 제16권4호
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• pp.455-463
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• 2006

충주시에 위치하고 있는 무릉 생활폐기물 매립장에 쌍극자 배열을 이용한 전기비저항 탐사를 수행하여 폐기물 매립장 내부와 주변지역에 대해 침출수 존재 여부와 존재할 경우 하류지역으로 유출경로를 분석하고자 하였다. 매립장 내부의 전기비저항 분포특성을 고려할 때 매립 후 시간이 경과하여 매립물질로부터 유도된 침출수가 측선 곳곳에서 하부 지반의 공극으로 스며들고 있는 것으로 분석된다. 또한 3개 측선 모두 공통적으로 단면도 왼쪽 지역에 고립된 이상대가 존재하고 이상대의 위치, 발달형태와 전기비저항 절대값 등을 종합적으로 고려할 때 상류, 중류 및 하류 지역에서 각각 발달된 전기비저항 이상대가 상호 연결 가능성이 대단히 높은 것으로 분석된다. 마지막으로 매립장 출입구 부근에 설치된 측선에 대한 전기비저항 탐사결과는 매립장 일부 구간에서 매립장 외부로 침출수가 유출했을 가능성이 대단히 크고 보다 정확한 유출경로 및 심도 등을 분석하기 위해 향후 다른 방법의 지구물리탐사 및 지구화학적방법을 이용하여 보다 많은 탐사가 필요한 것으로 판단된다.

• 보존과학회지
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• 제30권2호
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• pp.205-217
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• 2014

이 연구에서는 서산 신송리유적에서 출토된 청동기시대 석기를 대상으로 재질분석과 석재의 원산지를 검토하였다. 연구대상 석기는 점판암제 석재 1점, 석촉 반제품 2점, 갈판 1점 및 안산암질암 석촉 반제품 1점이다. 점판암은 유적지 일대에서 쉽게 관찰할 수 있는 암석이나, 안산암질암은 10km 이상 떨어진 부석면 간월도와 안면읍 황도리 등에서 산출된다. 석기 구성암석과 추정산지 암석에 대한 비교분석 결과, 점판암제 석기는 재질 및 암석광물학적 특징이 거의 동일하였으나, 안산암질암 석기는 추정산지 암석과 일부 다른 특징이 나타났다. 주원소, 미량원소, 호정 및 불호정원소에 대한 비교에서도 점판암제 석기와 추정산지 암석은 동일한 경향을 보였으나, 안산암질암 석기와 추정산지 암석은 다소 차이가 있다. 따라서 신송리유적에서 출토된 점판암제 석기는 유적 주변에 분포하는 암석을 원료로 제작한 자급형 석기로 해석된다. 그러나 안산암질암 석기는 외래형 석기로 추정되며, 광역적 조사를 비롯한 주변 유적에서 출토된 화산암제석기에 대한 연구를 병행하여 종합적 해석이 필요할 것으로 판단된다.

• 자원환경지질
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• 제50권4호
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• pp.313-324
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• 2017

촉트체치 지역은 남고비에 위치하며 석탄기 후기에서 페름기 초기에 관입한 흑운모 화강암 중 일부가 반암이 관입하면서 알카리 화강암화 된 부분과 관련된 동 광상이다. 말라카이트가 집중적으로 산출되는 지역은 녹니석, 녹렴석으로 변질된 프로필리틱 변질대가 광범위하게 나타난다. 격자지구화학탐사와 연장부 조사 결과 말라카이트가 산출되는 곳은 30개 지점으로 휴대용 XRF로 측정한 동함량은 1.080~18.300%로 나타났으며, 화학분석 결과 동함량은 13개 지점에서 각각 1.080%~32.900로 높게 나타났다. X-선 회전 분석결과와 현미경 관찰결과 동광물은 말라카이트가 주이며, 남동석, 퍼민제타이트, 황철석과 황동석 등이 가끔 산출되며, 그 외에 은 광물인 능홍은석이 산출된다. 또한 열수변질광물인 딕카이트가 산출되며, 변질산물인 방해석, 녹니석, 녹염석 등도 산출된다. 광화작용은 반암관입 후에 남은 잔류마그마에서 열수용액이 올라오면서 반암 주변 일부 화강암과 정단층 상반부에만 선택적으로 일어난 것으로 사료된다.

• 한국수산과학회지
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• 제46권4호
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• pp.424-436
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• 2013

Organic enrichment was investigated in surface sediments from the Yeoja and Gangjin Bays of Korea, which contain dense shellfish farms, in order to evaluate the contamination status and temporal changes in shellfish farming along these coasts. The degree of organic enrichment was determined using geochemical indicators (chemical oxygen demand, ignition loss, acid volatile sulfide, total organic carbon in sediments, and total nitrogen in sediments, ammonium and nitrate in pore water, and bioluminescence inhabitation for sediments). Temporal changes in organic enrichment conditions were detected by comparing our 2012 data to those previously reported from a survey conducted in 1999/2000. Organic enrichment was significantly higher in September than in May and July, in Gangjin Bay than in Yeoja Bay, and significantly higher in shellfish farms than in reference sites not used to culture shellfish. Ammonium concentrations in pore water were two orders of magnitude greater than nitrate concentrations, suggesting that these bays represent nitrogen-reducing environments.

• 자원환경지질
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• 제9권1호
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• pp.45-73
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• 1976

This study has been made for the enlargement of a previous work of 1964 which was carried out by an author of this work emphasizing the stratigraphy, micropaleontology, depositional environment, and structural tectonics of the studied area. The stratigraphic sequences of the area are groupped into four units: (1) basement of Pre-Cretaceous, (2) lower sediments of Late Cretaceous, (3) upper sediments of Late Cretaceous and (4) igneous rocks of Late Cretaceous and Tertiary (?). The oldest rocks consisting of schists and gneisses of Pre-Cambrian and schistose granite' of Jurassic age are exposed at the base of this area on which the thick Cretaceous sediments were deposited. These old rocks are unconformably overlain by the lower sedimens of Late Cretaceous composed of three members, an alternation of black shale and tuffaceous sediments, fine tuff and rhyollite flow in ascending order. The oily material was found from the black shales of the alternation m"ember as semi-solid greaselike material, oily order and microscopic granular spherical material and oily stain. The lower sediments are also overlain, in low-angleunconfromity, by the 'upper sediments having three members, an alternation of volcanic conglomerate and andesitic tuff, rhyollitic tuff and andesite flow in the same order. The igneous suit of diabase, diorites, biotite granite, porphyritic granite and porphyries of the latest Cretaceous and small exposure of pitchstone of Tertiary (?) intruded into the pre-existed rocks above mentioned. Considerable amount of ostra- coda microfossils have been chemically extracted from the black shales of the lower sediments and the identification of the fossils suggests that the depositional environment of the sediments were under fresh or brackish water condition. The distribution of the geology and its tectonic data also suggest a combination of dome and basin structures in the area of San-i peninsula and Jin-do as shown in fig. 8. Between these two units an anticlinal structure was constructed. As a result of this study, a seismic survey in a district between U-su-yong and north coast of Jin-do is recommended to determine the underground features.

• 자원환경지질
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• 제33권4호
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• pp.273-282
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• 2000

In order to investigate the extent and degree of arsenic and heavy metal contamination and the bioavailability of toxic elements around the abandoned mine in Korea, an environmental geochemical survey was undertaken in the Daduk mine. After appropriate preparation, tailings, soil, stream sediment, crop plant and fingernail samples were analysed for As, Cd, Cu, Pb and Zn by ICP-AES and ICP-MS. Elevated levels of 8,782 mg/kg As, 8.3 mg/kg Cd, 489 mg/kg Cu, 3,638 mg/kg Pb and 919 mg/kg Zn were found in tailings from the Daduk mine. These significant concentrations can impact on soils and sediments around the tailing ponds. Mean concentrations of As, Cd, Pb, Cu and Zn in soils are significantly higher than those in world average soil, especially for As and Pb. Element concentrations in sediments decrease with distance from the tailing ponds due to a dilution effect by the mixing of uncontaminated sediments. Arsenic and Cd are elevated in rice grains and stalks, and Cu and Zn concentrations in chinese cabbage, sesame and bean leaves are higher than the upper limit values for normal plant. Arsenic concentration in fingernails of farmers are higher than the normal level with a maximum value of 1.5 mg/kg. The post-ingestion bioavailability of toxic heavy metals in some paddy and farmland soils has been also investigated using the SBET (simple bioavailability extract test) method. The method utilises synthetic leaching fluids closelyanalogous to those of the human stomach. The quantities of As, Cd, Cu, Pb and Zn extracted from paddy soils after 1 hour indicated 15.9, 65.4, 46.2, 39.4 and 29.4% bioavailability, respectively and for farmland soils, 12.4, 26.0, 31.2, 29.3 and 19.4% bioavailability, respectively. The results of the SBET indicate that regular ingestion of soils by the local population could pose a potential health threat due to long-term toxic element exposure.