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Basic Research of the Paleo-Environmental Change and Possibility of Ancient Port Location Through Geomorphological Survey and Sediment Analysisin Hwaseong City (화성 당성 유적 일대의 지형 조사 및 퇴적물 분석을 통한 고환경 변화 및 고대 포구 입지 가능성 기초 연구)

  • Han, Min;Yang, Dong-Yoon;Lim, Jaesoo
    • Journal of The Geomorphological Association of Korea
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    • v.24 no.4
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    • pp.27-41
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    • 2017
  • In this study, geomorphological and geological research has been carried out to estimate the possibility of ancient port location near Hwaseong Dangseong. Geomorphological characteristics around Eunsupo were analyzed through comparison of past and present topographic maps and field survey. Grain size, age dating, and geochemical analysis on surface sediments and borehole sediments were performed. Through the geomorphological characteristics analysis, it was interpreted that Eunsupo area was submerged in seawater especially at high tide in the past, and that ships could approach to the inside of the area through the tidal channel which were developed in the area. It is also assumed that ships were anchored at a low elevation point in the area. The paleo-environmental change in the area was analyzed based on the classification of sedimentary environment using grain size distribution of surface and borehole sediments and geochemical analysis. It was confirmed that the geomorphological interpretation for the possibility of ancient port location coincided well with the paleo-environmental change interpreted through sediment analysis. This study is a basic study for estimating ancient port location, and it is expected that more accurate paleo-environmental changes will be restored through detailed geomorphological survey and additional borehole analysis in the future research.

A Study on the Positioning of the Korea Dental Hygienists Association(KDHA) - Based on Undergraduates in Dental Hygienics - (대한치과위생사협회의 포지셔닝에 관한 연구 -치위생과 재학생 대상-)

  • Kim, Bit-Na;Kwon, Hong-Min
    • Journal of dental hygiene science
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    • v.6 no.3
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    • pp.163-167
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    • 2006
  • The purpose of this study is to position the Korean Dental Hygienists Association(KDHA) for reserve dental hygienists as undergraduates, and thereby suggest KDHA's future potential businesses and its promising directions from comprehensive perspectives. To meet this goal, total 430 undergraduates in dental hygienics were asked to join questionnaire survey dating from November 28 to December 9, 2005. Then, the resulting data collected were analyzed using SPSS WIN 12.0. The results of data analysis can be outlined as follows: 1. Almost all of respondents(95.1%) recognized KDHA mainly via departmental faculty(37.7%), Internet(26.7%) and more. 2. It was found that KDHA's future potential businesses should be devoted primarily to promoting the right and benefit of dental hygienists, and secondly to business for their capability development. 3. In terms of joining the membership of KDHA, 73.0% of respondents showed desires to join KDHA certainly if they get relevant qualifications and 81.2% of respondents answered that it is necessary to pay membership fee to KDHA, if they join it. 4. A test about any possible associations with KDHA's positioning according to general characteristics showed that there were more or less significant differences in KDHA membership experience depending upon age(P = .022), and so was in the intention to join KDHA depending upon grade(P = .000), and in the membership fee payment depending upon both age(P = .000) and grade(P = .000) on statistical level.

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Petrochemistry of the Soyeonpyeong titaniferous iron ore deposits, South Korea (소연평도 함티타늄 자철광상의 암석지구화학적 연구)

  • Kim, Kyu Han;Lee, Jung Eun
    • Economic and Environmental Geology
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    • v.27 no.4
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    • pp.345-361
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    • 1994
  • Lens shaped titanomagnetite ore bodies in the Soyeonpyeong iron mine are embedded in amphibolites, which were intruded into Precambrian metasediments such as garnet-mica schist, marble, mica schist, and quartz schist. Mineral chemistry, K-Ar dating and hydrogen and oxygen stable isotopic analysis for the amphibolites and titanomagnetite ores were conducted to interpret petrogenesis of amphibolite and ore genesis of titanomagnetite iron ore deposits. Amphibolites of igneous origin have unusually high content of $TiO_2$, ranging from 0.94 to 6.39 wt.% with an average value of 4.05 wt.%. REE patterns of the different lithology of the amphibolite show the similar trend with an enrichment of LREE. Amphiboles of amphibolites are consist mainly of calcic amphiboles such as ferro-hornblende, tschermakite, ferroan pargasite, and ferroan pargasitic hornblende. K-Ar ages of hornblende from amphibolite and gneissic amphibolite were determined as $440.04{\pm}6.39Ma$ and $351.03{\pm}5.21Ma$, respectively. This indicates two metamorphic events of Paleozoic age in the Korean peninsula which are correlated with Altin orogeny in China. The titanomagnetite mineralization seems to have occurred before Cambrian age based on occurrence of orebodies and ages of host amphibolites. The Soyeonpyeong iron ores are composed mainly of titanomagnetite, ilmenite, and secondary minerals such as ilmenite and hercynite exsolved in titanomagnetite. The temperature and the oxygen fugacity estimated by the titanomagnetite-ilmenite geothermometer are $500{\sim}600^{\circ}C$ (ave. $550^{\circ}C$) and about $2{\pm}10^{-23}bar$, respectively. Hornblendes from ores and amphibolites which responsible for magnetite ore mineralization, have a relatively homogeneous isotopic composition ranging from +0.8 to +3.9 ‰ in ${\delta}^{18}O$ and from -87.8 to -113.3 ‰ in ${\delta}D$. The calculated oxygen and hydrogen isotopic compositions of the fluids which were in equilibrium with hornblende at $550^{\circ}C$, range from 2.8 to 5.9‰ in ${\delta}^{18}O_{H2O}$ and from -60.41 to -81.31 ‰ in ${\delta}D_{H2O}$. The ${\delta}^{18}O_{H2O}$ value of magnetite ore fluids are in between +6.4 to + 7.9 ‰. All of these values fall in the range of primary magmatic water. A slight oxygen shift means that $^{18}O$-depleted meteoric water be acted with basic fluids during immiscible processes between silicate and titaniferous oxide melt. Mineral chemistry, isotopic compositions, and occurences of amphibolites and orebodies, suggest that the titanomagnetite melt be separated immisciblely from the titaniferous basic magma.

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A Preliminary Study on Calculating Eruptive Volumes of Monogenetic Volcanoes and Volcanic Hazard Evaluation in Jeju Island (제주도 단성화산의 분화량 계산과 화산재해 평가에 대한 예비연구)

  • Ko, Bokyun;Yun, Sung-Hyo
    • The Journal of the Petrological Society of Korea
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    • v.25 no.2
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    • pp.143-149
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    • 2016
  • Eruptive volumes of three monogenetic volcanoes (Songaksan tuff ring, Biyangdo scoria cone, and Ilchulbong tuff cone) with the youngest eruption age are calculated using the model, applied to Auckland Volcanic Field in New Zealand, to investigate the volcanic eruption scale and to evaluate volcanic hazard of Jeju Island. Calculated eruptive volumes of the volcanoes are $24,987,557m^3$, $9,652,025m^3$, and $11,911,534m^3$, respectively, and the volumes include crater infill, tuff ring (tuff cone), scoria cone, and lava flow. Volcanic explosivity indices of Songaksan tuff ring, Biyangdo scoria cone, and Ilchulbong tuff cone are estimated based on the eruptive volumes to be 3, 2, and 3 respectively, and eruption type is Strombolian to Surtseyan. It is assumed that the amount of emitted sulfur dioxide gas is $2-8{\times}10^3kt/y$ according to the correlation between volcanic explosivity index and volcanic sulfur dioxide index. Recent age dating researches reveal evidences of several volcanic activities during the last 10,000 years indicating the possible volcanic eruption in Jeju Island in the near future. Therefore, it is necessary for appropriate researches regarding volcanic eruption of the island to be accomplished. In addition, establishment of the evaluation and preparation system for volcanic hazard based on the researches is required.

Geochemistry and K-Ar Age of the Imog Granite at the southwestern Part of the Hambaeg Basin, Korea (함백분지(咸白盆地) 남서부(南西部)에 분포(分布)하는 이목화강암(梨木花崗岩)의 지화학(地化學) 및 K-Ar 연대측정(年代測定))

  • Hong, Young Kook
    • Economic and Environmental Geology
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    • v.19 no.2
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    • pp.97-107
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    • 1986
  • The Cretaceous Imog granite is a calc·alkaline, subsolvus monzogranite and shows characteristics of "I-type" and "magnetite·series" granite by mineralogy and chemical composition. Many of the major and trace element characteristic of the Imog granite are consistent with a relationship by fractional crystallization of a basic magma. The primary magma of the granite derived from the subduction of oceanic crust at the destructive plate margin. The granite shows light REE enrichment with (Ce/Yb)N ratios of 7.77~12.55. All the REE patterns show Eu negative anomalies ($Eu/Eu^*=0.69$) in the pluton. The Imog granite at the southwestern part of the Hambaeg basin may be intruded along the tectonic intersections of the E-W and N-S lines such as deep faults and fractures. Radiometric age determination on the granite reveals as $96.7{\pm}2.0Ma$ by K-Ar dating on biotite.

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Morphological Correlation and Chronology of Lower Terrace Formations of Southeastern Coast of Korea (한국 남동해안 저위단구 퇴적층의 지형대비 및 형성시기 고찰)

  • Choi, Weon-Hack;Kim, Ju-Yong
    • Proceedings of the Korean Quaternary Association Conference
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    • 2005.10a
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    • pp.48-54
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    • 2005
  • Terrace morphology is so conspicuous in the south eastern coastal areas. Coastal terraces can be divided into 5 main surfaces, including beach and coastal alluvial plain(AP, $4{\sim}5m$), Low Terrace(LT, 8 $^{\sim}$ 25m), Middle Terrace(MT, 36 $^{\sim}$ 55m), High Terrace(HT, 63 $^{\sim}$ 86m) and upper High Terrace(uHT, above 90m). Among them Lower Terrace Formation is distributed between 8m and 20m in altitude. Both Tephra deposited of LT2 formation and OSL datings of sand layers in LT 2 and LT 3 Formations support the age of the LT 2 formation is MIS 5d or 5e, most probably 5e. The age of LT 3 is interpreted MIS 5a, based on tephra production in organic mud layers and OSL dating of sand deposits just above the beach pebbles of the LT 3. Particularly the transgression, possibly equivalent to the well-known Monastirrian episode in the Mediterranean Sea.

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A Study on the Patterns of Recollection and the Desires of Users in the Drama Series (드라마 <응답하라> 시리즈의 기억 회상과 시청자의 수용욕망 연구)

  • Ahn, Sang-Won;Kim, Hye-Bin
    • The Journal of the Korea Contents Association
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    • v.16 no.9
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    • pp.679-693
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    • 2016
  • The purposes of this study were to examine the patterns of recalling memories in the series and look into the desires of viewers disclosed in the process. Entering the 2010s, people got to recall their memories from the 1980s and 1990s. Nostalgia and retro became cultural products. What made the series, those depict the pure love, friendship, and family affection of main characters under age in those decades, so popular among the viewers? Finding a repeating pattern in recollection of the past, dating, and family love, the investigator saw that the pattern met the needs of viewers and thus analyzed their desires inherent in the series with a focus on its "narratives" and "characters." Their unique sounds effect and music established a micro-narrative that could be divided, thus allowing viewers to own certain scenes easily, which worked to make "non-existent" memories. Secondly, the series succeeded in capturing the desire of viewers living in the age of neoliberalism to reduce their fatigue from excessive choices by setting the characters in a contrived way and thus presenting the desire of maintaining the stable middle class world with no conflicts and the passive female characters. The recollections provided by the series, in the end, fill the desire and deficiency of the present beyond a simple return to the past.

Precambrian Crustal Evolution of the Korean Peninsula (한반도 선캠브리아 지각진화사)

  • Lee, Seung-Ryeol;Cho, Kyung-O
    • The Journal of the Petrological Society of Korea
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    • v.21 no.2
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    • pp.89-112
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    • 2012
  • The Korean Peninsula consists of three Precambrian blocks: Nangrim, Gyeonggi and Yeongnam massifs. Here we revisited previous stratigraphic relationships, largely based on new geochronologic data, and investigated the crustal evolution history of the Precambrian massifs. The Precambrian strata have been usually divided into lower crystalline basements and upper supracrustal rocks. The former has been considered as Archean or Paleoproterozoic in age, whereas the latter as Paleoproterozoic or later. However, both are revealed as the Paleoproterozoic (2.3-1.8 Ga) strata as a whole, and Archean strata are very limited in the Korean Peninsula. These make the previous stratigraphic system wrong and require reconsideration. The oldest age of the basement rocks can be dated as old as Paleoarchean, suggested by the occurrence of ~3.6 Ga inherited zircon. However, most of crust-forming materials were extracted from mantle around ~2.7 Ga, and produced major portions of crust materials at ~2.5 Ga, which make each massif a discrete continental mass. After that, all the massifs belonged to continental margin orogen during the Paleoproterozoic time, and experienced repeated intracrustal differentiation. After the final cratonization occurring at ~1.9-1.8 Ga, they were stabilized as continental platforms. The Nangrim and Gyeonggi massif included local sedimentary deposition as well as igneous activity during Meso-to Neoproterozoic, but the Yeongnam massif remained stable before the development of Paleozoic basin.

Paleomagnetic Study on Cretaceous Rocks in Haenam Area (해남지역의 백악기 암석에 대한 고지자기 연구)

  • 임무택;이윤수;강희철;김주용;박인화
    • Economic and Environmental Geology
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    • v.34 no.1
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    • pp.119-131
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    • 2001
  • A mean characteristic remanent magnetization was obtained for the first time in Korea from volcanic and pyroclastic sedimentary rocks distributed in Haenam Area, located in southwestern part of the Korean Peninsula. The age of the prevailing rocks in this area belongs mostly to Late Cretaceous, with a few exceptions of Early Cretaceous, mainly based on K/Ar whole rock age dating. Characteristic remanent magnetizations of these have both normal and reverse polarities with antipodal direction, which were interpreted to be the primary remanent magnetizations obtained by the ambient Earth's magnetic field at the time of formation of the concerned rocks. The source magnetic minerals of the remanent magnetization has been identified as magnetite. The mean direction of characteristic remanent magnetization obtained from the Late Cretaceous rocks in this study is Dm/Im=21.4 supper(o)/57.1 supper(o) (${\alpha}_{95}=13.4^{\circ}$, k=350.0). The paleomagnetic pole position calculated from this result for the Late Cretaceous, is $72.5^{\circ}N/199.9^{\circ}E$ (dp/dm= $14.2^{\circ}/19.5^{\circ}E$), which matches well with those of 80 Ma ($76.2^{\circ}N/198.9^{\circ}E$) and 90 Ma ($76.2^{\circ}N/200.1^{\circ}E$) of the Eurasian Continent's APWP (Apparent Polar Wander Path). This result strongly indicates that the studied area, belonging to the Eurasian Continent, have suffered very little geotectonic movement after the Late Cretaceous. The deflection of declination of remanence from Early Cretaceous rocks in the study area may indicate that the micro-block was counterclockwisely rotated with vertical axis between the late of Early Cretaceous and the early of Late Cretaceous.

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Effect of Satisfaction with the Marriage Support Policy on Marriage Intention among Unmarried Employed Men and Women - Focusing on Unmarried Employed Men and Women of Marriageable Age Residing in the Seoul City and Metropolitan Area - (취업미혼남녀의 결혼지원정책 만족도가 결혼의향에 미치는 영향 - 서울시 및 수도권 결혼적령기 취업 미혼남녀를 중심으로 -)

  • Park, Ju-Hee
    • Journal of Family Resource Management and Policy Review
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    • v.21 no.4
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    • pp.1-15
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    • 2017
  • The purpose of this study was to identify the effect of satisfaction with the marriage support policy on marriage intention among unmarried employed men and women. The study subjects included 300 unmarried working men and women aged over 30 years residing in the Seoul metropolitan area. First, according to the analysis of the subjects' overall tendency towards satisfaction with the marriage support policy and towards marriage intention, the marriage support policy gained the highest level of support in relation to housing for newlywed couples, which scored 3.29 (sd=.93), followed by improvements in corporate and family culture for the purposes of work-family compatibility at 3.24 (sd=.95), wedding loans at 3.18 (sd=1.01), and the paid leave system for marriage preparation at 3.12 (sd=.88). These variables scored slightly higher than the median 3 points. Conversely, satisfaction with the availability of marriage-related information and the provision of opportunities for dating scored 2.65 (sd=.88) and 2.78 (sd=.80), respectively, both of which were slightly lower than the median of 3. The overall mean score for satisfaction with the marriage support policy was 3.03 (sd=.95), which was slightly higher than the median of 3. In regards to marriage intention, the score was 3.32 (sd=1.15) points out of a perfect score of 5, which was slightly higher than the median. This indicated a slightly higher level in terms of the subjects' intention to marry. Second, a hierarchical regression analysis was performed to identify the effect of satisfaction with the marriage support policy on marriage intention among unmarried employed adults. Sociodemographic variables were entered as control variables in the regression at the first stage, and variables relating to satisfaction in a family-friendly social environment were entered at the second stage. When gender, age, educational level, monthly income, period of employment, working hours, and type of employment were inserted in the first stage of regression as control variables, gender, monthly income, period of employment, and type of employment were found to have a significant effect on marriage intention. Marriage intention was found to be greater in unmarried men with higher monthly incomes and longer periods spent working, and in unmarried working men and women engaged in tenured employment work. When variables relating to satisfaction with the marriage support policy were inserted in the second stage of regression, gender, monthly income, type of employment, and satisfaction with direct marriage support had significant effects on marriage intention. It was found that marriage intention was greater in unmarried men whose monthly income was higher, whose employment type was tenured work, and who showed greater satisfaction with direct marriage support.