• The Journal of the Petrological Society of Korea
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• v.10 no.2
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• pp.106-120
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• 2001

The Busan area in the northeastern part of the Ogcheon metamorphic zone, Korea, consists mainly of Precambrian Busan and Bakdallyeong gneiss complexes, Ogcheon metamorphic rocks and Mesozoic granitoids. The Busan gneiss complex shows Heart-shaped distribution laying down eastward, and is surrounded by the Ogcheon metamorphic rocks in the central part of the Busan area. In this study structural examination on the main constituent rocks (Busan gneiss complex and Ogcheon metamorphic rocks) was conducted to clarify the geological structure of the Ogcheon metamorphic zone in the Busan area. It indicates that the geological structure was formed at least by three phases of deformation. (1) Dl deformation: the formative period of the structural units of WNW trend (Sanjeoteo, Busan-II, Busan-I, and Chungiu nappes) and the mylonitic foliations related to the compression of NNE-SSW direction, (2) D2 deformation: the differential E-W shortening and N-S extension period of the structural units of WNW trend related to the compression of E-W or WNW-ESE directions, (3) D3 deformation: the formative period of the kink or open folds of E-W trend related to the compression of N-S direction in the eastern and southern parts of Busan area where the structural units of N-S or NNE trends reoriented owing to the intense D2 deformation were developed. These three phases of deformation are closely connected with the distribution of the structural units and the Heart-shaped Busan gneiss complex laying down eastward, and in this paper a new geodynamic model to the Heart-shaped Busan gneiss complex is suggested: Dl deformation-the zonal distribution of WNW trend with a constant width, D2 deformation - the formation of convex wedges northeastward and southward, D3 deformation - the formation of concave wedge westward.

• The Journal of the Petrological Society of Korea
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• v.6 no.2
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• pp.133-149
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• 1997

In the metapelites around the Ogcheon granite, the metamorphic grade increases from the biotite zone through the andalusite zone to the sillimanite zone towards the intrusion contact. In the metabasites around the Boeun granite, the metamorphic grade increases from transitional zone between the greenchist and amphibolite facies through the amphibolite facies to the upper amphibolite facies towards the intrusion contact. In the Doiri area locating near the intrusion contact of the Boeun granite, sillimanite- and andalusite-bearing metapelites are found with in 500 m away from the contact. The evidence described above indicates that the Ogcheon and Boeun granites caused low-P/T type contact metamorphism to the country rocks. The P-T condition of contact metamorphism due to the intrusion of the Ogcheon granite is $540{\pm}40^{circ}C, 2.8{\pm}0.9$ kb. The temperature condition of contact metamorphism due to the intrusion of the Boeun granite is $698{\pm}28^{\circ}C$. The wide compositional range of amphibole and plagioclase in the metabasites around the Boeun granite is due to the immisibility gab of amphibole and plagioclase and unstable relict composition resulted from an incomplete metamorphic reaction. The compositional range of stable amphibole and plagioclase decreases as a metamorphic grade increases due to a close of immiscibility gab. The thermal effect of contact metamorphism due to the intrusion of the Ogcheon and Boeun granites, are calculated using the CONTACT2 program based on a two dimensional finite difference method. In order to estimate the thermal effect of an introduced pluton, a circle with 10 km diameter and a triangle with 20 km side are used for the intrusion geometries of the Ogcheon granite and the Boeun granite, respectively. The results from the field and modeling studies suggest that the intrusion temperatures of the Ogcheon granite close to $800^{\circ}C$ and the intrusion temperature of the Boeun granite is higher than $1000^{\circ}C$. However, the intrusion temperatures can be lower than the suggested temperature, if the geothermal gradient prior to the intrusion of the Ogcheon and Boeun granites was higher than the normal continental grothermal gradient.

• Journal of the Korean earth science society
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• v.21 no.3
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• pp.302-314
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• 2000

Keumseong area in the southern part of the Jecheon city, the Ogcheon Belt, consists of Precambrian Dangdusan Metamorphic Complex, Dori Formation of the Choseon Supergroup, and Jurassic Jecheon Granite. The Dangdusan Metamorphic Complex consists of quartz schist, mica schist. quartzite and pegmatite. The Dori Formation is composed of mainly laminated limestone. The rocks in the study area have been undergone at least three phases of deformations since Paleozoic period. The Dangdusan Metamorphic Complex is outcrop at three areas in the study area, which are exposed along the faults and occurred as inlier within the Dori Formation. Previous authors interpreted the uplift of the Dangdusan Metamorphic Complex by the Dangdusan Fault, but we could not find any evidences related to the Dangdusan Fault. Thus, we interpret the uplift of the Dangdusan Metamorphic Complex due to the D$_2$ Weolgulri and Dangdusan thrusts and post-D$_2$ Jungbodeul, Kokyo and Jungjeonri faults. The uplift of the Busan Metamorphic Complex to the west of the study area was interpreted by ductile deformation. However, the Dangdusan Metamorphic Complex is formed by brittle thrusts and faults in this study. According to deformation sequence, the characters of deformations in the Choseon and Ogcheon suprergroups had been changed from ductile to brittle deformations through the time. Therefore, we interpret the Dangdusan Metamorphic Complex is exposed later than the Busan Metamorphic Complex.

• The Journal of the Petrological Society of Korea
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• v.23 no.2
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• pp.105-117
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• 2014

The Ogcheon and Joseon Supergroups are distributed in the Bonghwajae area, Jecheon-si, Chungcheongbuk-do, Korea which is located in the northeastern fore-end of the Ogcheon Metamorphic Zone. This paper researched the geological structures based on the geometric and kinematic characteristics and the forming sequence of the major multi-deformed rock and microstructures. Most of regional foliations are not the S0 bedding but the S0-1 composite foliations defined by the preferred orientation of stretching minerals, some are recognized as the S0-1-2 composite foliations by the preferred orientation of insoluble opaque minerals and cleavage lamella. The geological structures were formed at least by three phases of deformations i.e. NNE-SSW trending D1, E-W trending D2, N-S trending D3 compressions. The S0-1 composite foliation, which shows a similar zone-distribution trend of the constitution strata of the Ogcheon and Joseon Supergroups, trended WNW before D2 deformation, but it was reoriented into N-S which was parallel to the trend of S2 foliation by D2 deformation, and it was rearranged into NW, NE, N-S trends as it is now by D3 deformation. The structural characteristics of each deformation phase and the deformation history are very similar to those in the eastern domain of Busan area into which the Ogcheon and Joseon Supergroups in this area are extended as NNW trend. It is expected to be very valuable data in interpreting the tectonic evolution of the northeastern fore-end of the Ogcheon Metamorphic Zone.

• 전기의세계
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• v.25 no.6
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• pp.14-18
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• 1976

한국에 있어서의 초고압송전기술의 개발은 지난 6년동안 중요한 전진을 성취하였다. 한전은 초고압송변전설비의 건설을 추진하여 최초의 345kV 송변전설비의 건설공사를 완료하고 지난 10월 20일 역사적인 운전개시를 함으로써 한국에 초고압송전시대를 도래케 하였다. 이제 345kV 변전소의 설계에 대하여 구체적으로 소개할 수 있게 되었으므로 본고에서는 345kV 신옥천변전소의 설계를 중심으로하여 연결되는 송전계통, 변전소설계기준 및 변전소배치 등을 간추려보고자 한다. 사진1은 제1단계건설이 완료되어 운전을 개시한 345kV 신옥천 변전소의 전경이다.

• River and Culture
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• v.3 no.4
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• pp.68-75
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• 2007

• 열린충남
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• s.61
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• pp.35-43
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• 2013

• KLA journal
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• v.48 no.12 s.390
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• pp.48-51
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• 2007

• Korean Architects
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• no.1 s.345
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• pp.72-75
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• 1998

• 베이커리
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• no.12 s.425
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• pp.122-123
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• 2003