• Title/Summary/Keyword: 연대성

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Review of Radiometric Ages for Phanerozoic Granitoids in Southern Korean Peninsula (남한 지역 현생 화강암류의 연대측정 결과 정리)

  • Cheong, Chang-Sik;Kim, Nam-Hoon
    • The Journal of the Petrological Society of Korea
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    • v.21 no.2
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    • pp.173-192
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    • 2012
  • Previous age data were reviewed for 98 sites of Phanerozoic granitoids in the southern part of the Korean Peninsula. Subduction-related granitic magmatism has occurred in southeastern Korea since Early Permian. In the middle part of the Yeongnam massif, arc-related tonalites, trondhjemites, granodiorites, and monzonites were emplaced during Early Triassic. After Middle Triassic continental collision in central Korean Peninsula, post-collisional shoshonitic and high-K series and A-type granitoids were emplaced in the southwestern Gyeonggi massif and central Okcheon belt during Late Triassic. Early Jurassic calc-alkaline granitoids are mostly distributed in the middle part of the Yeongnam massif and Mt. Seorak area, northeastern Gyeonggi massif. On the other hand, Middle Jurassic calc-alkaline granitoids pervasively occur in the Okcheon belt and central Gyeonggi massif. This selective distribution could be attributed to the change in the position of trench, subduction angle, or the direction of subduction. Most Cretaceous and Paleogene granitoids are distributed in the Gyeongsang basin, with the latter emplaced exclusively along the eastern coastline. Outside the Gyeongsang basin, Cretaceous granitoids emplaced in relatively shallow depth occur in the Gyeonggi massif and central Okcheon belt.

Age of the volcanism and deposition determined from the Cretaceous strata of the islands of Yeosu-si (여수시 도서지역의 백악기층에 나타나는 화성활동 및 퇴적시기)

  • Park, Kye-Hun;Paik, In-Sung;Huh, Min
    • The Journal of the Petrological Society of Korea
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    • v.12 no.2
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    • pp.70-78
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    • 2003
  • Sado, Chudo, Mokdo, Nangdo, and Jeokgeumdo are the islands which belong to Hwajeong-myeon, Yeosu-si, Jeollanam-do and there are various kinds of volcanic rocks, volcaniclastic sedimentary rocks, and dinosaur-fossil bearing sedimentary rocks on these islands. This study is designed to constrain geologic ages of these volcanic and sedimentary rocks. K-Ar ages of these rocks indicate that the volcanism of this area occurred mainly during the period of 91.8 ${\pm}$ 3.5∼65.5 ${\pm}$ 1.3(l$\sigma$) Ma. Deposition ages of the sedimentary rocks were bracketed based on the ages of the volcanic rocks and observed field relationship between sedimentary and volcanic rocks. The oldest sedimentary deposit of the area is the volcanic pebble bearing conglomerate of the Jeokgeumdo and its deposition age is ca. 81 Ma or less. The deposition age of the Chudo shale, which belongs to stratigraphically upper sequence and bears many dinosaur footprints, is at least ca. 77 Ma. Conglomerate of the Mokdo was deposited at ca. 72∼70 Ma. The deposition age of the dinosaur fossil deposit of the Sado is at least ca. 65 Ma. All the investigated volcanic and sedimentary rocks of the Yeosu islands were formed during the late Cretaceous and dinosaurs lived until the latest Cretaceous in this area.

ESCO Case - 일본 ESCO사업의 최신동향

  • 에너지절약전문기업협회
    • The Magazine for Energy Service Companies
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    • s.69
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    • pp.48-53
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    • 2011
  • 2010년 11월 26일, 도쿄 신주쿠에서 에너지절약 지원 서비스에 관한 토론회, '에너지절약 ESCO페어 2010'이 개최되었다. 여기서는 경제산업성이 2009년에 실시한 "ESCO도입을 위한 정보제공 및 조사사업"에 따른 지역 금융기관과 사업자와의 연대에 관하여 논의하고, "국내 크레딧제도의 활용에 관하여"를 제목으로 한 세미나의 모습을 전달하며 기업이 발표한 ESCO도입 사례를 소개한다.

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A Study on the Territoriality and the Socio-spatial Characteristics of a Commoner's Settlement in Modern Times (${\cdot}$현대 민촌의 사회공간적 성격과 영역성 - 부여군 장암면 장하리의 사례 -)

  • Jeon Jong-Han
    • Journal of the Korean Geographical Society
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    • v.40 no.6 s.111
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    • pp.613-630
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    • 2005
  • In this article, the author inquired the multi-layered sphere of a commoner's settlement of Jangha-ri in modem times to approach the territoriality and socio-spatial characteristics of it. This settlement has originated in a lineage settlement of Jinju-Gang, and has experienced socio-spatial cohesion since its making(the 17th Century). Especially, it is found that the territoriality of Jangha-ri has fluctuated in times and has obtained multi-layeredness according to the human-nature relationship, to the social relationship, and to the political relationship of villagers. As a result, it is interpreted that the socio-spatial characteristics and territoriality of Jangha-ri in modem times do not only have a physical reality, but also social, political, cultural one.

The Effects of Mobile Smart-Work IT Resources of Resource Based View on the Work Efficiency : based on moderating effects of the perceived usefulness (자원기반관점(RBV)에서 모바일 스마트워크 IT자원이 업무효율성에 미치는 영향 - 지각된 유용성의 조절효과를 중심으로 -)

  • Lee, Min-Woo
    • Journal of Digital Convergence
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    • v.14 no.7
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    • pp.93-102
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    • 2016
  • The purpose of this study is to examine the effects of the Mobile Smart-Work IT resources on the work efficiency based on moderating effects of the perceived usefulness in the Resource Based View. The study has academic meanings and practical implications that studied widely based on moderating effects of the perceived usefulness through the Hierarchical regression furthermore on the existing study on hypothesis by standard multiple regression. The results showed that IT Infrastructure in the Mobile Smart-work IT resources by moderating effects of the perceived usefulness was found to bring positive effect on individual work efficiency and teamwork efficiency. On the other hand Business Application was found to bring positive effect on teamwork efficiency. Therefore, we expect that business firm and employees actively use the effects of the perceived usefulness with the trust that Mobile Smart-work IT resources bring positive effects on the work efficiency. It can improve this work efficiency and lead to strengthening the firm competitiveness.

A Study on the Meaning of Ecological Sustainability in the Ecological Ethics (생태적 지속가능성의 생태윤리적 의미에 대한 연구)

  • Byun, Sun-Yong
    • Journal of Ethics
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    • no.85
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    • pp.167-186
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    • 2012
  • This paper analyzes the meaning of sustainability in sustainable development in the ecological ethics, and suggests the importance of ecological sustainability. In the discussion of ecological sustainability the relation between sustainability and change should be regarded as not conflictual but interactive. The concept 'ecological' in this context means network, and the concept 'sustainability' means the relationship between changing being(or beings) which constitutes ecological system and its unchanging being(or whole relation). So there are two axes of human and ecological system, and three elements namely network which means mutual dependence of human and nature, sustainability which means the maintenance of ecological relations, and responsibility which humans should take for the sustainability, in the ecological sustainability. The maintenance between being and relations of beings, changing sustainability, the priority of being to non-being, mutual interdependence on the basis of solidarity of beings are important values in the ecological sustainability.

A Study on Benzene Synthesis for the Radiocarbon Dating (방사성탄소 연대측정을 위한 벤젠합성법 연구)

  • Kim, Nak Bae;Woo, Hyung Joo;Hong, Wan;Cho, Soo Young
    • Analytical Science and Technology
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    • v.5 no.1
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    • pp.25-31
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    • 1992
  • A benzene synthesizer was manufactured and has been used for the treatment of the various samples such as wood, charcoal, shell and soil for radiocarbon dating using liquid scintillation counter. The experimental conditions were optimized in each successive step of the synthesis of carbon dioxide, acetylene and the final product of benzene. Fifteen hours operation of the benzene synthesizer leads to product yields consistently in excess of 85% based on the content of calcium carbonate for the organic samples. Purity of the synthesized benzene was measured to be more than 99.9% by GC/MS.

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Geochemical Significance of $^{14}C$ Age from the Dongrae Hot Spring Water (동래온천수의 $^{14}C$ 연대의 지구과학적 의의)

  • Lee, Seung-Gu;Nakamura, Toshio;Kim, Tong-Kwon;Ohta, Tomoko;Kim, Hyoung-Chan;Lee, Tae-Jong
    • Economic and Environmental Geology
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    • v.42 no.6
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    • pp.541-548
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    • 2009
  • The Dongrae thermal water area located at the southeastern marginal part of the Korean Peninsula is one of the oldest hot springs in Korea. The Dongrae thermal water shows Na-Cl type of water chemistry, whereas the shallow cold groundwater is Ca(-Na)-$HCO_3$ type. In this paper, we discuss the age of the Dongrae hot spring, i.e. groundwater cycle among meteoric water-surface water-shallow groundwater-hot spring water. The $^{87}Sr/^{86}Sr$ ratios of the thermal water in Dongrae area range from 0.705663 to 0.705688 and are lower than those of groundwater, surface water and rain water as well as aquifer bearing granite. These Sr isotopic signatures in the Dongrae thermal water indicate that the circulation rate between thermal water and current meteoric water including groundwater, surface water and rain water in the Dongrae area should be very slow. The $^{14}C$ age of the Dongrae hot spring water range from $1,271{\pm}36$ BP(before present) to $2,467{\pm}36$ BP whereas that of the shallow groundwater is $-495{\pm}33$ BP. This suggests that the period of groundwater cycle among meteoric water, surface water, shallow groundwater and hot spring should be more than 1,270 years. Then, it also indicates that the present Dongrae hot spring may be a mixed water between the old thermal water heated for at least 1,270 years and the present shallow cold groundwater.

Geochemical and Geochronological Studies on Metaigneous Rocks in the Gyemyeongsan Formation, Northwestern Okcheon Metamorphic Belt and their Tectonic Implication (옥천변성대 북서부 계명산층 내 변성화성암류의 지구화학 및 지구연대학적 연구와 그 지구조적 의의)

  • 박종길;김성원;오창환;김형식
    • The Journal of the Petrological Society of Korea
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    • v.12 no.4
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    • pp.155-169
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    • 2003
  • In the northwest Okcheon metamorphic belt, the metaigneous rocks in the Gyemyeongsan Formation have wider chemical ranges for major, trace and REE elements compared with metaigneous rocks in the Munjuri Formation and do not represent bimodal igneous activity which is characteristic for a continental rifting. The metaigneous rocks in the Munjuri Formation are regarded as products of single magmatic evolution, whereas those in the Gyemyeongsan Formation may be formed through multiple magmatic episodes. The felsic metavolcanic rocks in the Gyemyeongsan Formation show weaker Eu negative anomalies compared with those in the Munjuri Formation but those in both formations show similar degrees of enrichment from LREE to HREE. The metabasites in the Munjuri Formation do not show Eu anomalies but those in the Gyemyeongsan Formation show both positive and negative Eu anomalies(0.59