• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2005년도 춘계 학술발표회 논문집
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• pp.109-110
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• 2005

• 자원환경지질
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• 제55권6호
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• pp.597-616
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• 2022

The Chungnam basin is a crucial area for studying the Mesozoic crustal evolutionary history of the Korean Peninsula. This study reports the revised geology and new isotopic ages from the northeastern Chungnam Basin based on detailed geological mapping and LA-ICP-MS zircon U-Pb analysis. Our renewed geologic map defines intra-basin, basin-bounding, and basement fault systems closely related to hydrothermal gold-bearing quartz vein injections. Here, we propose the directions of (micro)structural and geochronological future work to address issues on the relationship between the tectonic process, basin evolution, and hydrothermal fluid migration in the southwestern Korean Peninsula.

• 자원환경지질
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• 제25권4호
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• pp.435-446
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• 1992

REE, major and trace elements analyses of the Jurassic Daebo granite and Cretaceous Bulguksa granite were carried out to interpet their petrogenesis and relationships between petrogenesis and tectonics. Analytical results are summarized as follows. (1) $SiO_2$ content of the Bulguksa granite (aver. 74.6%) are significantly higher than those of the Daebo granite (aver. 68.1%). Major elements of $TiO_2$, $Al_2O_3$, $P_2O_5$, CaO, MgO, Total FeO, and trace elements of Co, V and Sr are negatively correlated with $SiO_2$. Incompatible elements such as Ba, Sr, Y, Zr and HREE are contained differently in the Bulguksa granites distributed in between Okchon folded belt and Kyongsang sedimentary basin. (2) Trace element abundances show a good discrimination between two goups of granitic rocks. Ba, Sr and V are enriched in Daebo granites, while Zn and Cr are depleted in them. (3) Jurassic granites have quite different Eu anomalies and REE patterns from those of Cretaceous granites: Large negative Eu anomaly in the former and mild or absent Eu anomaly in the latter. The large Eu negative of Cretaceous granitic rocks are interpreted as a differentiated product of fractional crystallization of granitic magma from the upper mantle. Meanwhile, the Daebo plutonic rocks was resulted from the partial melting of subcrustal material or crustal contamination during ascending granitic magma from the mantle. Senario of igneous activities of Mesozoic age in South Korea was proposed based on Kula-Pacific ridge subduction model.

• 자원환경지질
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• 제51권6호
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• pp.579-587
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• 2018

후기 트라이아스기~전기 쥬라기의 후 충돌 분지 상위에 전기 및 중기 쥬라기의 호 내부 분지가 중첩되어 나타나는 충남분지는 대동누층군의 분포 지역으로 잘 알려져 있으며, 중생대 퇴적분지의 진화와 지구조 운동과의 상관관계를 규명하는데 매우 중요한 지역이다. 본 연구에서는 충남분지에 발달하고 있는 지질구조 연구의 일환으로서 분지 중앙부에 위치하는 성주리향사 및 주변 지역에 대한 지표 지질조사를 통해 구조기하학적 해석을 수행하였다. 연구지역에 발달하는 대표적인 지질구조로는 성주리향사와 더불어 옥마단층, 옥마습곡, 백운사단층이 있다. 연구의 대상인 성주리향사는 층리 자세의 변화에 따라 크게 남서부 및 북동부의 두 영역으로 나뉘며, 각 영역의 힌지가 저점으로 모이는 이중침강습곡의 형태를 보인다. 성주리향사 남서부 및 옥마습곡에 대한 하향 투영을 통해 작성된 단면을 해석한 결과, 옥마단층 및 옥마습곡은 기반암 내의 단층이 상위의 퇴적암으로 전파하면서 발달한 구조로 판단되며, 성주리향사는 옥마단층의 단층말단 상부에 형성된 배사 및 향사의 일부로 해석된다. 본 연구의 결과는 충남분지 및 더 나아가 중생대 조산대로서 한반도 남서부에 기록되어 있는 변형사를 밝히는 데에 유용하게 활용될 수 있을 것으로 생각된다.

• 자원환경지질
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• 제8권4호
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• pp.223-230
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• 1975

남한(南韓)은 지구조적(地構造的)으로 4개의 지질구(地質區)로 나누어 진다. 경기육괴(京畿陸塊)와 영남육괴(嶺南陸塊)는 선(先)캠브리아기(紀)의 편마암(片麻岩)과 편암(片岩)으로 구성되어 있다. 결천지향사대(決川地向斜帶)는 소위 지나방향(支那方向)인 서남남동(西南南東)으로 한반도(韓半島)를 비스듬히 가로지르고 있다. 옥천지향사대(沃川地向斜帶)의 북동부(北東部)는 주(主)로 고생대(古生代)와 중생대(中生代) 초기의 퇴적암층(堆積岩層)으로 되어있고 서남부(西南部)는 후기 선(先)캠프리아기(紀)의 변성암층군(變成岩層群)으로 되어있다. 경상분지는 백악기(白堊紀)의 두꺼운 육성퇴적층(陸成堆積層)과 안산암류(安山岩類)로 되어있다. 제3기(第三紀)의 몇 개의 소분지(小盆地)가 한반도 동남부와 제주도에 분포(分布)하고 주로 해성층(海成層)과 현무암류로 되어있다. 쥬라기(紀)의 대보화강암(大寶花崗岩)이 경기육괴(京畿陸塊), 영남육괴(嶺南陸塊), 결천지향사대내(決川地向斜帶內)에 지나방향(支那方向)으로 관입분포(貫入分布)한다. 한편 백악기(白堊紀)의 불국사(佛國寺) 화강암(花崗岩)은 경상분지에 분산분포(分散分布)한다.

• 자원환경지질
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• 제1권1호
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• pp.35-46
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• 1968

Some of geologists in Korea recently postlated that Okchon system previously known to be precambrian age was the metamorphosed sediments of post-Chosen (Ordovician and pre-Kyeongsang (late Jurassic to Cretaceous) periods, or even definitely of Triassic period simply on the basis of the fact that Okcheon system overlies the Great Limestone series of Chosen system of Camber-ordovician age, and of other few assumptions of minor importance. As a result of such correlation, thick series of metasediments and Okcheon system of unknown age were established in this particular region and vaguely correlated to Paleozoic and Mesozoic sediments. Recent study done by the author reveled that: 1) only the upper Okcheon bed of S. Nakamura was true Okcheon system, and the middle and lower Okcheon beds were excluded, because they were correlated to Cambrian and Permian sediments resfectively, 2) Sangnaeri, Seochangri, and rengam formations of unknown age, and Baekhwasan, Jobong, and Ihwaryeong formations of Okcheon system of also unknown age were the metamorphosed Yangdeok system of Cambrian age, all of these formations were differentiated by the previous workers and were equivalent to the middle Okcheon system of S. Nakamure, and. 3) These metamorphosed Yangdeok system overlaid apparently the Great Limestone series in forms of overthrust and klippe which were produced by the orogeny took place during post-Daedong and pre-Kyeongsang period (probably middle to the Jurassic). The Sobaeksan Range, folded mountain Chains was also formed by this orogeny. Thus, Okcheon system newly defined by the author is precambrain age and consists in ascending order of Kemyenogsan, Hyangsan dolomite, and Daehangsan quartzite formation which were previously classified into metasediments of unknown age, and Munjuri, and Hwangkanri, formations which were differentiated into Okcheon system unknown age by the previous workers, but are of reversed sequence. Myeongori and Bukrori formations of Okcheon System are regard by the author as part of Hwangkanri formation. Few other assumption of minor important taken by the previous workers as their positive evidences are carefully explained that they were misinterpreted.

• 한국석유지질학회:학술대회논문집
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• 한국석유지질학회 2000년도 제7차 학술발표회 발표논문집
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• pp.57-72
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• 2000

The Murzuk Basin covers an area in excess of $350,000{\cal}km^2$, and is one of several intra-cratonic sag basins located on the Saharan Platform of North Africa. Compared with some of these basins, the Murzuk Basin has a relatively simple structure and stratigraphy, probably as a result of it's location on a the East Saharan Craton. The basin contains a sedimentary fill which reaches a thickness of about $4,000{\cal}m$ in the basin centre. This fill can be divided into a predominantly marine Paleozoic section, and a continental Mesozoic section. The principal hydrocarbon play consists of a glacial-marine sandstone reservoir of Cambro-Ordovician age, sourced and sealed by overlying Silurian shales. The present day borders of the basin are defined by tectonic uplifts, each of multi-phase generation, and the present day basin geometry bears little relation to the more extensive Early Palaeozoic sedimentary basin within which the reservoir and source rocks were deposited. The key to the understanding of the Cambro-Ordovician play is the relative timing of oil generation compared to the Cretaceous and Tertiary inversion tectonics which influenced source burial depth, reactivated faults and reorganised migration pathways. At the present day only a limited area of the basin centre remains within the oil generating window. Modelling of the timing and distribution of source rock maturity uses input data from AFTA and fluid inclusion studies to define palaeo temperatures, shale velocity work to estimate maximum burial depth and source rock geochemistry to define kinetics and pseudo-Ro. Migration pathways are investigated through structural analysis. The majority of the discovered fields and identified exploration prospects in the Murzuk Basin involve traps associated with high angle reverse faults. Extensional faulting occurred in the Cambro-Ordovician and this was followed by repeated compressional movements during Late Silurian, Late Carboniferous, Mid Cretaceous and Tertiary, each associated with regional uplift and erosion.