• 암석학회지
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• 제22권2호
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• pp.153-177
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• 2013

국토의 효율적 관리를 위한 각종 지질정보자료로 활용될 수 있도록 ArcGIS 10.1 프로그램, 1 대 250,000의 수치지질도 및 지형도를 사용하여 전남과 광주지역 구성암류의 지질시대별 및 암층별 분포율과 분포특성을 도출하였다. 전남지역 의 지질시대는 모두 7개로 대분되며, 분포율은 백악기, 선캠브리아기, 쥬라기, 제4기, 시대미상, 석탄기-삼첩기 및 삼첩기의 순으로 감소하며, 그 중 전자 넷이 94.80%를 이루어 거의 대부분을 차지한다. 구성암층은 선캠브리아기 15개, 시대미상 6개, 석탄기-삼첩기 3개, 삼첩기 2개, 쥬라기 4개, 백악기 25개 그리고 제4기 2개로서 도합 57개에 달한다. 분포율은 백악기의 Kav(산성 화산암류+유문암 및 유문암질 응회암)와 Kiv(중성 및 염기성 화산암류+안산암 및 안산암질 응회암), 선캠브리아기의 지리산편마암복합체(소백산육괴)인 화강편마암과 반상변정질 편마암, 제4기의 충적층, 쥬라기의 화강암류와 엽리상화강암의 순으로 감소하며 이들이 도합 71.68%의 우세한 값을 이룬다. 그 중 뚜렷하게 우세한 Kav는 전남지역의 북부, 서부, 중부, 동부 및 남부에 보다 넓게 발달하며, 특히 서부인 신안 및 목포-영암, 남부인 해남일대에 더 우세하게 분포하는 양상을 보인다. 광주지역의 지질시대는 모두 5개로 대분되고 분포율은 쥬라기, 제4기, 백악기, 선캠브리아기 그리고 시대미상의 순으로 감소하며, 그 중 전자 넷이 98.95%를 가져 거의 전부를 이룬다. 구성암층은 선캠브리아기 1개, 시대미상 2개, 쥬라기 2개, 백악기 6개와 제4기 1개로서 도합 12개에 달한다. 분포율은 쥬라기 화강암류, 제4기 충적층, 선캠브리아기의 소백산편마암복합체인 화강편마암과 백악기 Kiv 순으로 감소하고 도합 91.30%를 가져 그 대부분을 차지하며 전자 둘에서 뚜렷하게 우세하다. 가장 우세한 화강암류는 대부분 광주지역 남서부에서 북동부 방향에 걸쳐 발달한다. 충적층은 대부분 황룡강, 영산강과 이들의 합류부에 발달하며, 북구에서는 영산강변에서 용두평야 그리고 광산구에서는 영산강과 황룡강 합류부에서 동계평야 등을 이룬다.

• 암석학회지
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• 제21권2호
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• pp.129-150
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• 2012

본 논문에서는 옥천, 청산, 문경 부운령, 부산 지역에서 작성된 암상구분에 의한 상세한 지질도, 변형단계별 지질구조와 미구조, 변형작용과 변성작용 사이의 상대적 시간관계 등에 대한 종합적인 연구결과와 옥천누층군에서 최근까지 보고된 절대 및 화석 연대자료로부터 중부 옥천대의 지구조 발달과정을 새롭게 고찰해 보았다. 첫 번째 지구조운동($D^*$)은 원경기육괴를 북부 경기육괴(현재의 경기육괴)와 남부 경기육괴(부산 및 박달령 편마암복합체)로 분리시키는 열곡작용에 의해 특징 지워진다. 전기 고생대 동안에는 조선누층군과 이에 상응하는 옥천누층군의 하위층군(석영사질암, 이질암, 탄산염질암, 염기성질암)이 옥천열곡분지에 퇴적 및 분출 관입되었고, 후기 고생대 동안에는 평안누층군과 이에 상응하는 옥천누층군의 상위층군(역질암, 이질암, 산성질암)이 퇴적 및 분출 관입되었다. 두 번째 지구조운동(옥천-청산 지구조운동/송림조산운동: D1)은 후기 페름기~중기 트라이아스기 동안에 발생하였고, D1은 전기단계의 옥천 아지구조운동(D1a)과 후기단계의 청산 아지구조운동(D1b)으로 구분된다. D1a는 북부 경기육괴와 남부 경기육괴의 결합 즉 옥천열곡분지의 닫힘운동과 관련하여 발생하였으며, 그 초기단계에는 옥천누층군에 조립흑운모, 석류석, 십자석 등 중압형 변성광물의 성장과 관련된 M1 중압형 변성작용을 발생시켰고 그 후기단계에는 옥천 중압형 변성암류를 남동-버젼스의 몇몇 나쁘로서 발굴시켰다. 그 결과 옥천변성대에서는 남동-버젼스의 지구조단위들이 형성되고 옥천누층군에는 이에 수반되어 대규모 칼집습곡, 광역엽리, 신장선구조가 형성되었다. D1b는 (북)북동-(남)남서의 압축지구조 환경하에서 발생하여 남중국판(경기육괴와 옥천변성대)과 북중국판(영남육괴와 태백산대)을 결합시켰다. 주요 지질구조로는 결합부의 선단부와 후미부에 (북)북동-버젼스 내지 (남)남서-버젼스를 갖는 (서)북서 방향의 충상단층이 형성되고, 결합부의 측면부에는 북북동 방향의 우수 주향-이동성 청산전단대와 조선 및 평안누층군에 북북동 방향의 직립습곡이 형성되었으며, 한반도에는 대동분지가 형성되었다. 그 이후, 후기 트라이아스기~전기 쥬라기의 대동층군이 퇴적되고, 세 번째 지구조운동(호남 지구조운동/대보조산운동: D2)은 전기~후기 쥬라기 동안에 북북동 방향의 우수 주향-이동성 호남전단운동의 횡압축응력 지구조환경하에서 발생하여 옥천누층군에 비대칭 파랑습곡과 조선 및 평안누층군에 북북동 방향의 횡와습곡과 후기 트라이아기 이전의 지층군이 대동층군의 상부로 충상하는 동남동-버젼스의 충상단층을 형성시켰다. M2 홍주석-규선석형 접촉변성작용은 D2의 휴식기에 해당하는 중기 쥬라기에 대보 화강암류의 관입에 의해 발생하였다. 네 번째 지구조운동(청마리 지구조운동: D3)은 전기 백악기에 남-북 방향의 압축지구조 환경하에서 발생하여 북북동 방향의 좌수 주향-이동성 전단운동에 수반된 당겨-열림형 백악기 퇴적분지를 형성시켰다. M3 후퇴변성작용은 주로 D2 이후에 발생하여 옥천누층군에 녹니석 반상변정을 결정시켰다. D3 이후 옥천지역에서는 기생 킹크습곡과 함께 대규모 금강 끌림습곡을 수반하는 좌수향 금강단층운동(금강 지구조운동: D4)이 발생하였고 이들 킹크습곡은 후기 백악기의 산성 암맥에 의해 관입된다.

• 기술사
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• 제10권2호
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• pp.13-26
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• 1977

The Kum-Ho river basin is one of the densely populated area having more than 35% of the total population and it was also well irrigated since ealier days in the Nackdong River Basin Most of the easily developed source of surface water are fully utilized, and at this moment the basin is at the stage that no more surface water can be made available under the present rapid development of economic condition. Since surface water supplies from the basin have become more difficult to obtain, the ground water resources must be thoroughly investigated and utilized greatly hereafter. In economic ground of the basin what part could ground water play\ulcorner In what quantities and, for what uses could it be put\ulcorner The answer to these questions can be relatively simple; the ground water resources in the basin can be put at almost any desired use and almost anywhere in the basin. The area of the basin is at about 2088km$^2$ in the middle part of Nackdong River Basin and it is located along the Seoul-Pusan Express Highway. The mean annual rainfall is about 974.7m/m, most of which falls from June to September during the monsoon. Accumulated wet period is appeared approximately after every 8 year's accumulated dry-period with the duration of 5 years. The water bearing formations in the basin include unconsolidated alluvial deposits in Age of Quatenary, saprolite derived from weathered crystalline rocks, Kyongsang sedimentary formations of the period from late Jurassic to Cretaceouse, and igneouse rocks ranging of the Age from Mesozoic to Cenozoic. The most productive ground water reservoir in the basin is calcareouse shale and sandstones of Kyongsan system, which occupies about 66% of the total area.

• 자원환경지질
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• 제32권3호
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• pp.227-236
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• 1999

The Daeyou pegmatite is located at the central westerm part of the peninsula. Geology of the mine area consists mainy of pre-Combrian granite gneiss and leucoratic gneiss which are intruded by Mesozoic granites. The pegmatite deposits occur within granite gneiss. Most of pegmatites contain quartz, perthite, microcline-perthite, microcline, sodic plagioclase and tourmaline as dominant minerals with accessory minerals of mica (muscovite, biotite, sericite)and pyrite. Tourmaline occurs as four types: 1) unaltered single crystals, 2) patially sericitized grains bordered by sericite assemblage, 3) tourmaline intergrown with feldspar and qurtz grains, and 4) tourmaline introduced veinlet/ On the basic of optical, X-ray diffraction and chemical analysis, the composition of tourmaline mostly falls on the schorl-elbaite join, in the composition of tourmaline mostly falls on the schorl-elbraite join, in the composition of schorl end member from 0 to about 50%. In spite of the different occurrences, chemical composition of tourmaline shows the limited ranges as follows: $SiO_{2}$ (34.53~35.01 wt.%), $Al_{2}O_{3}$ (33.58~34.26wt.%), FeO (13.73~14.17wt.%), $Na_{2}O$ (1.60~1.72wt.%), MgO (0.56~0.72wt.%), MnO (0.12~0.18wt.%), CaO (0.02~0.06wt.%), $K_{2}O$(0.02~0.03wt.%) $TiO_{2}$ (0.02~0.05wt.%) and $Cr_{2}O_{3}$ (0.02~0.03wt.%). K-Ar ages of the muscovite and sericite fall between 1010$\pm$15 and 1074$\pm$16Ma and between 161.56$\pm$3.09 and 161.67$\pm$Ma, respectivrly. This means that hydrothrmal alteration occurred during middle Jurassic, whereas the pegmatite was initally formed during the late proterozoic age.

• 자원환경지질
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• 제16권2호
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• pp.111-123
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• 1983

The studied area is situated in tho southern part of the Ogcheon fold belt, where the "Ogcheon Group" is widespread with Jurassic and Cretaceous intrusions. The regional stratigraphy may be divided into three formations, the lower pebble bearing phyllitic, the middle dark grey phyllitic, and the upper black phyllitic formations. For the purposes of the present study, the area has been partitioned to three structural subareas based on major fold axes and fault line. The main subjects of the research have been discussed from two different points, multiple deformation and minor-micro fold styles. The former is analyzed by pebble elongation, folding and lineation in a pebbly formation as well as schistosity, crenulation cleavage and crenulated lineation in the phyllitic formation. The later describes the characteristic features of fold style in each formation and structural subarea. Although minor fold axes within broad pelitic rocks usually tend to trend northeast and to plunge northward, most of these were probably formed by two stages, first a similar fold phase and second a kink fold phase. Measured structural elements indicate that crenulation cleavage in phyllite formed parallel to fold axes of folded pebble followed a NE phase of first deformation and a fold axes of pebbles diagonal to bedding of phyllite are represented by a NW phase of a second deformation. Microscopically, quartz and mica grains form a micro fold enabling one to establish tectonic levels which occur in different deformation modes in each stratigraphic sequence. Microtextures such as crenulation cleavage, kink band, aggregate band of mica and pressure shadows of porphyroblast of quartz related to qarnet and staurolite may suggest the time relation of crystallization and tectonism. The result of this study may conform that three deformation phase, NE first phase-NE second phase-NW phase, occurred in the area.

• 자원환경지질
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• 제14권2호
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• pp.55-76
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• 1981

Southwestern contact zone of the Boeun granodiorite occurs near the thrust fault between the Ogcheon Group and Majeonri Limestone Formation. Ogcheon Group, metasediments composed of the Munjuri Formation, Changri Formation, and unconformably overlying Hwanggangri Formation, belongs to greenschist facies of regional metamorphism accompanied with deformation of two fold axes, $N10^{\circ}E$ and $N45-65^{\circ}E$ directions. Basic metamorphic rocks occurring in the Changri and Limestone Formations are the meta-basalts and meta-diabases of tholeiitic basalt series. The meta-basalts intruded in the Changri Formation as sills, whereas the meta-diabases in the Changri and Limestone Formations as stocks in appearance. They are considered to have emplaced before the formation of two fold axes and related with the thrust fault, based on the geologic setting of the area. The metamorphic facies are identified to be greenschist facies to epidote-amphibolite facies for the meta-basalt, and epidote-amphibolite facies for the meta-diabases. It is interpreted that such a variety of facies was related from the combination of earlier deuteric alteration and later regional metamorphism. The metasediments in southwestern contact zont of the Boeun granodiorite which is a product of later syntectonic intrusion of middle Jurassic in age, show pyroxene-hornfels facies near the contact and amphibole-horenfels facies away from the contact to the mineral zoning in the contact metamorphic aureole of the Limestone Formation, based on the paragenetic analysis of mineral assemblages. The Limestone in the area appears to be considerably $SiO_2-CaO-MgO-CO_2-H_2O$ can be adopted to evaluate equilibrium conditions of the mineral assemblages in each mineral zone. It is revealed that a temperature gradient was existed accross the contact aureole ranging from the higher igneous side to lower sedimentary side, whereas no clear trend of $XCO_2$ variation appears but high mole fraction. The tremolite diopside-quartz-calcite assemblages occurs in common through the most mineral zones of contact aureole that is in good agreement with the equivalent reaction curve which extends over a wide range of $T-XCO_2$ conditions.

• 자원환경지질
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• 제11권3호
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• pp.99-108
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• 1978

The Gum-Ho river basin is one of the densely populated area having more than 35% of the total population and it was also well irrigated since earlier days in the Nackdong river basin. Most of the easily developed source of surface water are fully utilized, and at this moment the basin is at the stage that no more :surface water can be made available under the present rapid development of economic condition. Since surface water supplies from the basin have become more difficult to obtain, the ground water resources must be thoroughly investigated and utilized greatly hereafter. In economic ground of the basin what part could ground water play? In what quantities and, for what uses could it be put? The answer to these questions can be relatively simple;the ground water resources in the basin can be put at almost any desired use and almost anywhere in the basin The area of the basin is at about $2088km^2$ in the middle part of Nackdong river basin and it is located along the Seoul-Pusan express highway. The mean annual rainfall is about 974.7mm, most of which falls from June to September during the monsoon. Accumulated is appeared approximately after every 8 year's accumlated dry period with the duration of 5 years. The water bearing formation in the basin include unconsolidated alluvial deposits in Age of Quaternary, saprolite derived from weathered crystalline rocks, Gyongsang sedimentary formations of the period from late Jurassic to Cretaceouse, and igneouse rocks ranging of the Age from Mesozoic to Cenozoic. The most productive ground water reservoir in the basin is calcareous shale and sandstones of Gyongsang system, which occupies about 66% of the total area. The results of aquifer test on Gyongsang sedimentary formation show that average pumping capacity of a well drilled into the formation with drilling diameter and average depth of $8{\frac{1}{2}}$ inch and 136m is $738m^3/day$ and also average specific capacity of those well is estimated $77.8m^3/D/M$. Total amount of the ground water reserved in the basin is approximately estimated at 37 billion metric tons, being equivalent 18 years total precipitations, among which 7 billion metric tons of portable ground water can be easily utilized in depth of 200 meters.

• 자원환경지질
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• 제29권3호
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• pp.293-304
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• 1996

The Wolchul Mt. area is composed of a biotite granite and a pink feldspar granite. These granites are distinctly different in terms of their field occurrence, mineralogy, trace element and REE composition, as well as their isotope ages. The biotite granite has higher ferromagnesian elements and lower lithophile trace element abundances than the pink feldspar granite. The biotite granite has high Sr and Ba while the pink feldspar granite has high Rb. On the Rb-Sr-Ba diagram the biotite granite plots as a granodiorite while the pink feldspar granite belongs to a strongly differentiated granite. The ${\Sigma}$ LREE/ ${\Sigma}$ REE for the biotite granite is 0.95 and for the pink feldspar granite it is 0.88. The ratio shows a steep decrese in LREE while HREE is essentially constant. Based on the Eu/Sm, $[La/Lu]_{cN}$ and low Eu(-), the biotite granite has quartz diorite to granodiorite composition while the pink feldspar granite, with a relatively high Eu(-) anomaly, falls into the monzo- to syenogranite classification. The silica vs. trace element diagrams for the two granites indicate that the biotite granite could have formed near to a continental margin or volcanic island setting environment while the pink feldspar granite formed within a continental plate or as result of plate collision. The biotite granite has a U-Pb zircon age of 175 Ma, i.e. Middle Jurassic. The pink feldspar granite is younger, it has a K-Ar orthoclase age $93.6{\pm}1.5$ Ma which is Late Cretaceous age.

• 자원환경지질
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• 제32권4호
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• pp.353-363
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• 1999

한반도와 중국 동부에 있어서 주라계와 백약계의 경계는 해성층의 결여로 구획이 곤란하고 경계상하가 연속적 지층을 이루고 있어 상부주라-하부백약계로 파악한다. 이는 하나의 광역적 부정합간 지층단위이므로 자성속(慈城束)이란 지층명이 적당하다. 그 위의 백약계인 경상속(慶尙束)은 다시 두 개의 부정합간 단위로 분류되는데 경상분지의 신동층군과 하양층군을 대표로 하는 단위(Hauterivian-하부Albian)와 동분지의 유천 화산암층군을 대표로 하는 단위(상부Albian-상부백약계)가 그들이다. 즉, 한반도 전역의 상부주라-백약계는 이들 3개의 부정집합간 단위로 나누인다. 상부주라-하부백약계 하위의 부정합은 주라기 중기 재지 후기의 대보변동에 기인하고 동 단위 상위의 부정합은 재령강(載寧江)변동에 기인한다. 유천아속(亞束)(상부Albian-상부백약계) 하위의 부정합은 유천(兪川)변동에 기안하는 것으로 이는 러시아 북동부와 연해주 일대에도 널리 인정된다, 상위는 널리 분포합은 신생대 초의 변동의 산물이다. 상부주라-백악계의 퇴적을 개관하건데 하부단위(자성속)는 북한에는 널리 분포하여 화산암이 많으나 남한에는 소규모의 묘곡층 등이 알려져 있다. 그 위의 중부단위(신동 및 하양층군 해당의 하부백약계)는 한반도 전역에 분산 분포하나 경상분지가 대표적으로 큰 분지이며 이곳의 충후는 북한의 배(倍)에 달하고 역암의 양도 훨씬 많다. 상부단위(유천아속)는 남한에는 널리 분포하고 화산암이 대부분이나 북한에는 예성강분지의 봉화산층군 밖에는 알려져 잇지 않고 화산암이 없다. 중부단위의 경우 각 퇴적층은 현저한 주기성을 보인다. 이 주기성은 남한과 북한의 동시기 지층의 상호대비의 기준이 되지 못할 가능성이 있다. 경상분지의 하향층군이 보여주는 주기성을 국지적 지각의 지괴운동의 차이에 따라 분지의 남부와 북부가 현저히 다르다. 이 사실에 비추어 보면 멀리 떨어진 두 분지의 동시기 지층들은 지반각지의 국지적 개별적 운동에 따라 서로 다른 퇴적주기를 보일 수 있다. 상부주라-백약계의 퇴적에는 대채로 보아 화산활동이 수반했다. 북한의 자성속에는 칼크-알칼리 및 알칼리 중성 및 산성의 화산암류가 수반했다. 남한의 하부백야계 상부에는 알칼리-준알칼리 현무암 및 안산암이 수반했다. 남한의 유천아속은 칼크-알칼리 안산암 및 유뮨암이 대부분이다. 3개 부정합간 단위의 분표양상을 개관하면 하부는 주로 북한에 분포하고, 중부는 남북한에 공통으로 분포하고 상부는 특별히 남한 남부에 주로 분포하여 시간의 경과에 따라 태평양 쪽으로 분포지대가 단계적으로 이동했음을 알 수 있다. 백악기 동안의 남한의 분지형성에 대해서 대하여는 북동향 주향이동단층들의 좌수향 운동에 크게 기인했을 것으로 해석했다.

• 자원환경지질
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• 제6권4호
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• pp.201-216
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• 1973

Being believed thus far to be distributed in the wide areas in the vicinity of Seoul, the capital city of Korea, the Yonchon System in its type locality in Yonchon-gun from which the name derived was never previously traced down or correlated to the Precambrian metamorphic complex in Seoul area where the present study was carried out. Due to in accessibility to Yonchon area, the writer also could not trace the system down to the area studied so as to correlate them. The present study endeavored to differentiate general stratigraphy and interprete the structure of the metamorphic complex in the area. In spite of the complexity of structure and rapid changes in lithofacies of the complex, it was succeeded to find out the key bed by which the stratigraphy and structure of the area could be straightened out. The keybeds were the Buchon limestone bed in the western parts of the area; Daisongri quartzite bed cropped out in the southeastern area; Jangrak quartzite bed scattered in the several localities in the northwest, southwest, and eastern parts of the area; and Earn quartzite bed isolated in the eastern part of the area. These keybeds together with the broad regional structure made it possible to differentiated the Precambrian rocks in ascending order into the Kyonggi metamorphic complex, Jangrak group and Chunsung group which are in clinounconformable relation, and the first complex were again separated in ascending order into Buchon, Sihung, and Yangpyong metermorphic groups. Althcugh it has being vaguely called as the Yonchon system thus far, the Kyonggi metamorphic complex have never been studied before. The complex might, however, belong to early to early-middle Precambrian age. The Jangrak and Chunsung group were correlated to the Sangwon system in North Korea by the writer (1972), but it became apparent that the rocks of the groups have different lithology and highly metamorphosd than those of the Sangwon system which has thick sequence of limestone and slightly metamorphosed. Being deposited in the margin of the basin, it is natural that the groups poccess terrestrial sediments rather than limestone, yet no explanation is at hand as to what was the cause of bringing such difference in grade of metamorphism. Thus the writer attempted to correlate the both groups to those of pre-Sangwon and post-Yonchon which might be middle to early-late Precambrian time. Judging from difference in grade of deformation and unconformity between the Kyonggi metamorphic complex, Jangrak group, and Chunsung group, three stages of orogeny were established: the Kyonggi, Jangrak orogenies, and Chunsung disturbance toward younger age. It is rather astonishing to point out that the structure of these Precambrian formations. was not effected by Daebo orogeny of Jurassic age. The post-tectonic block faulting was accompanied by these orogenies, and in consequence NNE and N-S trending faults were originated. These faulting were intermittented and repeated until Daebo orogeny at which granites intruded along these faults. The manifestation of alignment of these faults is indicated by the parallel and straight linear development of valleys and streams in the Kyonggi Massifland.