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The relationship between the residual of Taean Mado shipwreck No.3 and physical properties of sediments (태안 마도3호선 잔존과 퇴적물 물성의 연계성)

  • Lee, Sang-Hee;Jung, Yong-Hwa;Lee, Young-Hyun;Kim, Jin-Hoo
    • Journal of Advanced Marine Engineering and Technology
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    • v.41 no.3
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    • pp.269-275
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    • 2017
  • Shipwreck remains below the seabed not only effect the ocean currents and tides, but influence the physical properties of sediments and sedimentary environments that comprise the seabed. In particular, the influence of local shipwrecks discovered buried in the seabed on the sediment is visible. In this study, sediments were collected from the surrounding area of Taean Mado No.3 shipwreck using grab samplers and vibro-corers. The physical properties of these sediments were analyzed to evaluate the impact of the Taean Mado shipwreck No.3 remains. Sediment core analysis by means of density and ultrasonic velocity showed that shear strength tended to increase with depth, whereas moisture content and porosity tended to decrease with depth. Grain size analysis results are shown in terms of Folk's classification, where the grain size of the core samples in the study area indicate mud or sandy mud, and that of the grab sample indicates a muddy sand. Results of the sedimentation rate analysis indicate a rate of 2.84 cm/year and carbon dating of the 150 cm deep seashell indicates the Neolithic age. These sediments were analyzed for the study of the relationship between the Taean Mado shipwreck No.3 remains and the physical properties of the sediment.

The Development of the Hantan River Basin, Korea and the Age of the Sediment on the top of the Chongok Basalt (한탄강유역의 발달과정과 전곡현무암 위의 퇴적물의 연대)

  • Bae, Kidong
    • The Korean Journal of Quaternary Research
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    • v.3 no.1
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    • pp.87-101
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    • 1989
  • The development of the Hantan river basin can be divided into three stages. The first stage include the ancient Hantan channel system prior to the Chongokni basalt which yield dates of about 0.6 mya from the K/Ar dating method. During this period the Baekuyri formation was formed. The Baekuyri formation is widely observed under the Chongokni basalt along the current river system. The second stage is the period when stream channels stayed on the top of the basalt plateau. Aggradation and deggradation were continued by meandering and braiding channel systems until major stream channel was formed. The currently remaining deposit on the top of the basalt was formed by lacustrine and fluvial systems in this period. During this period Pleistocene hominid was present on edge of water and flood plain and left Paleolithic material. This period was begun at the time of the final basalt flow dated about 300,000 BP. The third stage is designed for the time when the Hantan river channel was dropped down to a level from which the channel could not influence the top of the basalt any more No more deposit could be formed but erosion by surface water has been continued on the top of the basalt since then. The dropping of the Hantan river channel was probably not very long after the final flow of the basalt. Because of frost action and heavy concentrated precipitation in the basin area along with blocky and clumnar joint structure of the basalt, erosional process of the basalt is believed to have been carried out within a relatively short time. The lowering of the Hantan river channel was probably completed in a cycle of major fluctuation of world cimate. Also, the redclay on the top of the basalt is believed to have been formed during a warm period around 200,000 BP, which accords with the climatic change suggested above fair1y well. The Paleolithic materials in tile deposits fell accordingly into approximately same time period.

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Quaternary Toham Basin (제4기 토함분지)

  • Choi Sung-Ja;Hong Dukgeun;Chwae Ueechan;Kim Myungjin;Lee Seog-kyu;Murray Andrew S.
    • Economic and Environmental Geology
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    • v.37 no.5
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    • pp.533-541
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    • 2004
  • A steadily consolidated conglomerate formation (CCF) is developed thickly around Tabjeong-ri and Janghang-ri to the east of Tohamsan, Gyeongju City. The CCF has been regarded to a basal conglomerate, Cheonbug Conglomerate, of the Yonil Group by Tateiwa (1924). Son et al. (2000) correlated the CCF to the Songjeon Formation, which occupies the southwestern block of Tertiary Waup Basin. However, the Songjeon Formation stratigraphically does not face to the extension of the CCF. OSL (Optically Stimulated Luminescence) data on the reddish brown to bluish gray psammitic layers, which are intercalated in the CCF, yielded to 85∼92 ka. Therefore, the age of CCF constrains to the last interglacial stage (MIS 5c-5e) rather than the Early Miocene Cheonbug Conglomerate. The Late Pleistocene Tohamsan Formation (TF) is newly named to the CCF and is subdivided to megabreccias and boulders. A rectangular basin, in which the TF is accumulated, is bounded by Oedong and Yonil faults (segments of Yonil Tectonic Line) and is given a name of Toham Basin. Neotectonically, Pliocene EW-transpression gave an effect of the top-up-to-the-west reverse faulting and the accompanied normal fault movement during the last interglacial age (ca. 100 ka). The basin is graben type, in which basin fills are composed of collapsed colluvial deposits, TF.

Geologic Age of Quartz Schist - Quartzite from Yeongam and Yeongsanpo Areas around Southwestern Part of Ogcheon Belt (옥천대 서남부 영암과 영산포 석영편암-규암의 지질시대)

  • Choi, Sung-Ja;Kim, Dong-Yeon;Song, Kyo-Young
    • Economic and Environmental Geology
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    • v.49 no.2
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    • pp.155-165
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    • 2016
  • Quartz schist - quartzite is often intercalated in metasedimentary rocks of Ogcheon belt or aligned parallel to the boundary between Yeongnam massif and Ogcheon belt. However, stratigraphic sequence and or geologic age of the rocks has been still variable among authors as Precambrian or Paleozoic. In this study, we carried out SHRIMP U-Pb age data of detrital zircons from Yeongam and Yeongsanpo areas and compared ours with other zircon ages from other areas. The detrital zircons from the studied area show no age younger than 1.8 Ga but yielded clusters at Neoarchean (2.5 Ga) and Paleoproterozoic (1.8 Ga). On the other hand, the age range of zircon U-Pb dating of Paleozoic quartzites yielded from Archean to middle Paleozoic and clusters at Paleoproterozoic, Neoproterozoic and Paleozoic. The characteristics of the zircon age range and the dominant age peak might become a key to classify the Proterozoic to Paleozoic quartz schists-quartzites, which ages are still remained under controversy. Based on the statistical results of the zircon ages in this study, quartz schist - quartzite from Yeongam and Yeongsanpo is considered to be deposited during Proterozoic.

SHRIMP U-Pb Age of the Early Jurassic Deformed Granites in the Aneui Quadrangle, SW Yeongnam Massif (영남육괴 남서부 안의도폭 지역 초기 쥬라기 변형 화강암류의 SHRIMP U-Pb 연대)

  • Seo, Jaehyeon;Song, Yong-Sun;Park, Kye-Hun
    • Economic and Environmental Geology
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    • v.49 no.2
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    • pp.147-153
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    • 2016
  • SHRIMP U-Pb age determination was carried out for deformed granites in the Aneui quadrangle, SW Yeongnam Massif. Dating of zircons from a highly deformed mylonitic granite with banded structure and a relatively less deformed porphyritic to augenic granites, that were known as Precambrian gneisses, yielded the same age of ca. 195 Ma. On the basis of this result and previous age data, Early to Middle Mesozoic igneous activity around the Aneui area was interpreted as follows; Subduction-related granitic magmatism started with the intrusion of the Hamyang Granite in the middle Triassic (ca. 225-219 Ma) mainly in the west of the area and ended with syenitic intrusion at the end of Triassic period (ca, 220-210 Ma). After a relatively short period of quiescency, granitic magmatism restarted with the intrusion of magma forming deformed granites dated in this study at the Early Jurassic of ca. 195 Ma and continued to ca. 189 Ma and dioritic intrusion was associated around the late stage of granitic magmatism.

A Study on Problems and Improvement of Personal Protective Regulations in Security Industry Act (경비업법상 신변보호 관련 규정의 문제점과 개선방안)

  • Park, Jung-Sub
    • Korean Security Journal
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    • no.51
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    • pp.81-100
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    • 2017
  • Recently, Crime patterns in our society are diversifying as followed on the urbanization of population and the influx of immgrants. Existing murder, kidnap, sexual assault, etc. Especially, the crimes such as school violence, dating violence, domestic violence, violent abuse and even social hatred a crime, motiveless crime are spreading into every phase of national life. Due to the social situation, the sharp increase in demand for personal protection, the scale of private security industry has been constantly expanded. Following this trend, the personal protective regulations in Security Industry Act has been revised several times since the it was enacted in 1995. However, despite the fact that the legal and institutional aspects should have been amended and improved systematically according to the industrial development, the regulations adopted initially adopted has been maintained so far, which have resulted in various problems as they could not coincide with the purpose of private security, being divorced from the reality of private security industry and social changes. Especially, in the case of personal protection service and facility security service, the legal requirements of both services are identical with each other in terms. Such legal systems may cause confusion to security businesses and employees, or the police managing and supervising them, regarding the scope and duties of security services. In order to improve such problems, the regulations of permission requirement that the personal protective regulations in Security Industry Act should be revised system. In this study, relevant personal protection provisions prescribed in the Security Industry Act have been reviewed critically in this paper. And also the regulations were review of those personal protection provisions enacted in security industry Act, so that the improvement plan for the personal protection provisions that are apposite to the cases in this country could be suggested in order to amend the current laws and provide real grounds for the law enforcement.

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Late Holocene Paleoceanography from Core Sediments in the Admiralty Bay and Maxwell Bay, King George Island, Antarctica (남극 킹 죠지 섬 에드미럴티 만과 멕스웰 만 시추 퇴적물의 홀로세 후기 고해양환 경 연구)

  • 박병권;윤호일
    • 한국해양학회지
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    • v.30 no.4
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    • pp.302-319
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    • 1995
  • The geochemical properties, sedimentation rates, foraminiferal distributions, and oxygen and carbon isotope records of sediment from Cores S-2 and S-19 were studied to investigate late Holocene paleoceanographic and paleoclimatic changes of the admiralty and Maxwell Bay, King George Island, Antarctica. Total organic carbon contents increased from the lower part to the upper part of Cores S-2 and S-19, whereas calcium carbonate contents decreased from the lower part to the upper part of Cores S-2 and s-19,whereas calcium carbonate contents decreased from the lower part to the upper part of Cores S-2 and S-19. Twenty-seven foraminiferal species were identified, and Globocassidurina biora was mostly a bundant in sediment samples. The sedimentation rates ranged from 24 cm/kyr to 237 cm/kyr based on /SUP 14/C-age dating of G. biora. The sedimentation rates increased rapidly in the upper part of the Cores. б/SUP 18/O values ranged from 0.3% to 6.2% and б/SUP 13/C values ranged from -3.0% to 0.0% with several fluctuations of the values. The lowest part of Core S-2, at 128 cmbsf in depth, had a /SUP 14/C-age of 3,100${\pm}$60 yr B.P. and the lowest part of Core S-19, at 230 cmbsf in depth, of 7,400${\pm}$ yr B.P. The results of geochemical and sedimentological analyses of the core sediments suggested five stages of paleoceanographic and paleoclimatic changes as follows: war,-cold stage of 7,500∼6,500 yr B.P., cold stage of 6,500∼3,600 yr B.P., cold-warm stage of 3,600∼2,770 yr B.P., warm stage of 2,770∼2,380 yr B.P. and cold-warm stage of 2,380∼2,100 yr B.P.

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Composition of volatile organic components on ballpoint pen inks by HS-SPME GC/MS (HS-SPME GC/MS를 이용한 볼펜잉크의 휘발성 성분 분석)

  • Choi, Mi-Jung;Kim, Chang-Seong;Sun, Yale-Shik;Park, Sung-Woo
    • Analytical Science and Technology
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    • v.23 no.4
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    • pp.414-422
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    • 2010
  • In forensic examinations of question document, analysis about inks components and the dating of ink entries is often of considerable importance and forensic examination of inks is principally concerned with the classification and comparison of chemically complex mixtures. The authenticity about inks analysis of a questioned document may be examined through the analysis of inks used to TLC, HPLC/MS, GC/MS, LDI/MS. We collected 56 difference types of black ballpoint pen inks manufactured from 5 country groups. We identified major 6 species volatile organic components (VOCs), ethylbenzene ($0.089-0.244\;{\mu}g$/mL), o-xylene ($0.072-0.331\;{\mu}g$/mL), m,p-xylene ($0.062-0.318\;{\mu}g$/mL), benzene ($0.003-0.173\;{\mu}g$/mL), 1,1-dichloroethylene ($0.003-0.295\;{\mu}g$/mL), toluene ($0.007-0.484\;{\mu}g$/mL) using HS-SPME GC/MS. The results of this study indicated that determined VOCs of black ballpoint pen inks could make a discriminating tool of inks analysis for forensic question document and can supply methodology for classification and identification of between ballpoints pen inks.

Lacquer Layers and Making Methods of the Wooden Coffin Excavated from the Nongso Tomb of Unrimri, Sunchang in Korea (순창 운림리 농소고분 출토 목관 칠 분석을 통한 제작방법 연구)

  • Lee, Hye Youn
    • Journal of Conservation Science
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    • v.33 no.5
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    • pp.355-362
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    • 2017
  • The Nongso tomb of Sunchang was built in a relatively deep place; hence there was little damage from grave robbers. The tomb was completely filled with a large amount of charcoal, and therefore the wooden coffin was excavated in relatively good condition. On the basis of the structure of the tombs, excavated artifacts, and radiocarbon dating results, the tomb is estimated to be from between the late Goryeo and the early Joseon period. The wooden coffin excavated is double-layered structures consisting of an outer coffin and an inner coffin. The outside of the wooden coffin is thickly lacquered and decorated with yellow letters and white motifs. An analysis of the pigments' components revealed that the major component of the letters was gold (Au) and the major component of the motifs was silver (Ag). The coffin lacquer had three layers: a pigment layer, a yellowish-brown layer, and a black layer. The wooden bases of the coffins were painted with a black substance, such as soot, as mineral elements were not detected in the black layer. The yellowish-brown layer is presumed to be refined lacquer. From the analysis of the structure of the layers and pigments, we can estimate the method was adopted for making lacquer for wooden coffin. It is assumed that the method used gold leaf and gold powder. The form of the pigment and the internal structure are likely to be gold leaf, but the shape of the surface letters appears to have been formed using gold powder. This study will serve as important information for understanding lacquer making techniques at the time of the tombs' construction by confirming the making method through reproduction experiments using gold leaf and gold powder.

Paleomagnetism and K-Ar Age of Volcanic Rocks from Guryongpo Area, Korea (구룡포에서 산출(産出)되는 화산암(火山岩)에 대(對)한 고지자기(古地磁氣)와 K-Ar연령(年齡))

  • Kim, Kwang Ho;Won, Jong Kwan;Matsuda, Jun-ichi;Nagao, Keisuke;Lee, Moon Won
    • Economic and Environmental Geology
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    • v.19 no.3
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    • pp.231-237
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    • 1986
  • Samples of porphyries, andesites, decites and sandstones were collected from 14 sites in order to study paleomagnetism and to determine K-Ar age in Guryongpo area. K-Ar age dating indicates that porphyries and volcanic rocks formed 41.7 and 22.7~19.4Ma, respectively. The mean direction of remanent magnetization for each site was generally well grouped after alternating field demagnetization. Both normal and reversed directions are present. The mean magnetic direction of the porphyries of Late Eocene and that of the volcanic rocks of Late Oligocene to Early Miocene have similar, easterly declinations. Overall magnetic direction is $Dm=43.8^{\circ}$, $Im=53.5^{\circ}$, ${\alpha}95=12.2^{\circ}$. the reliability of the observed paleomagnetic directions is ascertained by the presence of normal and reversed polarities. This is also conformed by the similarity of the declinations of the normal and reversed polarities. Observed easterly declinations in this area are attributed to local clockwise rotation of the land mass by approximately 40~50 degrees since early Miocene.

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