• 제목/요약/키워드: Age Dating

검색결과 294건 처리시간 0.024초

Microstructural Features and K-Ar Ages of Fault Gouges from Quaternary Faults along the Northern Yangsan Fault, SE Korea

  • Chang Oh Choo;Tae Woo Chang;Kounghoon Nam;Jong-Tae Kim;Chang-Ju Lee;Gyo-Cheol Jeong
    • 지질공학
    • /
    • 제33권1호
    • /
    • pp.121-136
    • /
    • 2023
  • Microstructural characterization, identification of mineral assemblages, and K-Ar age dating of fault gouges from five Quaternary fault sites segmented along the northern Yangsan Fault, SE Korea were performed to understand formation condition and multiple activity of faults. The mean and median sizes of particles of bulk gouges vary among the studied faults: 1.75 ㎛ and 1.43 ㎛ for the Danguri Fault, 1.94 ㎛ and 1.79 ㎛ for the Yukjae Fault, 5.57 ㎛ and 4.16 ㎛ for the Yugye Fault, and 5.55 ㎛ and 2.31 ㎛ for the Bogyeongsa Fault. Fault gouges contain abundant secondary minerals, including smectite, chlorite, illite, kaolinite, laumontite, and mordenite, which are found in association with quartz and feldspar. K-Ar dating of the fault gouges (both bulk samples and separate size fractions) yields ages ranging from 59.1 to 18.8 Ma, with bulk ages of 47.6 Ma for the Yukjae Fault, 59.1 Ma for the Ansim Fault, 39.4 Ma for the Yugye Fault, and 22.6 Ma for the Bogyeongsa Fault. The finer fractions generally have younger K-Ar ages compared with the coarser fractions, and the finest fraction (<0.2 ㎛) is the youngest for each fault. Hydrothermal alteration of the gouges is considered to have occurred under low-temperature (100~200℃) conditions during faulting. Microstructural features and clay mineral assemblages of fault gouges and brecciated rocks should be considered when interpreting fault events and reactivation, in addition to age dating of faulting.

방사성탄소연대측정 (Radiocarbon Dating)

  • 이현주;황진주;백현주
    • 보존과학연구
    • /
    • 통권23호
    • /
    • pp.197-214
    • /
    • 2002
  • It is very important to determine the age of the Cultural Properties in archeology. In about 1950, W.F. Libby and a team of scientists at the University of Chicago developed the Radiocarbon Dating technique. Radiocarbon($^14$C) Dating is probably one of the most widely used and best known absolute dating methods. Radiocarbon ages are conventionally specified to the year 1950. This year is 0 BP year. BP is the initial of Before Present. The $^14$C within an organism is continually decaying into stable carbon isotopes. When $^14$C decays, it emits a $\beta$ - particle with an energy content of 156 KeV and becomes 14N. Only the $\beta$ - particle is detected by Liquid Scintillation Counting. $^14$C has a half life of 5730 years. It has been used to date samples as old as 50,000 years. Radiocarbon determinations can be obtained on organic material : wood, charcoal, shell, etc. The results of radiocarbon dating using Benzene Synthesizer and Liquid Scintillation Counter are KCP539 $4030\pm60$BP year, KCP540 $3980\pm60$BP year, KCP575 $4870\pm50$, KCP576 $100\pm50$BP year, KCP577 $130\pm50$BP yea and KCP578 $210\pm70$BP year.

  • PDF

울산 천곡동 유적의 방사성탄소연대측정연구 (The Study on the Radiocarbon Dating of Cheongok-dong Archeaological site, Ulsan)

  • 이현주;송희정
    • 보존과학연구
    • /
    • 통권27호
    • /
    • pp.181-201
    • /
    • 2006
  • In this study, radiocarbon dating by the benzene synthesis method and liquid scintillation counting method were performed for the age determination of coal sample at the Cheongok-dong archaeologicalsite, Ulsan. The results of radiocarbon age(BP year) are section Ga #1 $2920\pm50$ BP year, section Ga #5 $3100\pm55$BP year, section Ga #6 $2820\pm60$ BP year, section Na #5 $2650\pm50$ BP year. These ages were converted to calibrated age(AD/BC year) using high precision curve. The products on the excavation of Cheongok-dong archaeological site, Ulsan, section Ga #1 BC 1260-980 BC, section Ga #5 BC1460-1200 BC, section Ga #6 BC 1110~830 BC, section Na #5 BC 920-760 BC. Comparison of samples with radiocarbon and archaeological ages for revealed the approximation.

  • PDF

진주 장흥리 와요지 유적의 절대편년연구 (The Study of Absolute Dating on Jinju Janghungri Kiln site.)

  • 이현주;김대웅;홍종욱;심일운
    • 보존과학연구
    • /
    • 통권26호
    • /
    • pp.189-202
    • /
    • 2005
  • This study carried out to understand thermoluminescence dating of ancient tiles at Jinju Janghungri Kilin site. Also radiocarbon dating by the benzene synthesis method and Liquid scintillation counting method were performed for comparison for the agedetermination of charcoal sample at the obtained same site.1st and 2nd glow curve were obtained according to the typical method thermoluminescence. Plateau tests of revealed the proper temperature range to be $300~440^{\circ}C$ Palaeodose average values were formed to the 2.44Gy.Annual dose of ancient tiles was calculated from soil samples and ancient tiles it self by measuring alpha radiation dose, potassium concentrations and water contents respectively. Annual dose average values were calculated to be 7.012mGy/yr.The radiocarbon age(BP year) was converted to calibrated age(AD/BC year) using high precision curve. Radiocarbon ages were calculated to be AD 15~17 .Comparison of samples with their radiocarbon and thermoluminescence ages for revealed the in range the AD 15~17. This result means that the measured absolute ages are in good agreement with each other within the margin of error.

  • PDF

남제주 사람 발자국 화석을 포함한 지층의 층서와 지질 연대에 대한 고찰 (Review on the Stratigraphy and Geological Age of the Hominid Footprints-bearing Strata, Jeju Island, Korea)

  • 김경수;김정률
    • 한국지구과학회지
    • /
    • 제27권2호
    • /
    • pp.236-246
    • /
    • 2006
  • 송악산과 사람 발자국 화석지 주변에서 측정된 절대 연대 측정 결과와 야외 지질 조사를 근거로 할 때, 하모리-송악산 지역의 층서는 하부로부터 광해악 현무암, 명명되지 않은 퇴적층, 송악산 응회암, 하모리층 및 사구층으로 구성되어 있으며, 발자국 화석이 산출되는 사계리 지역은 하부로부터 광해악 현무암, 사람 발자국 화석 산출 지층 그리고 사구층으로 구성되어 있다. 하모리층은 송악산 응회암이 형성된 후 퇴적된 지층이라는 규정과 절대 연령 측정 결과 및 현지에서 조사된 바에 의하면, 사람 발자국 화석이 산출되는 지층은 하모리-송악산 지역의 송악산 응회암층 상부에 놓이는 하모리층이 아니라 하부에 분포하는 명명되지 않은 퇴적층과 대비된다. 따라서 사람 발자국 화석의 형성 시기는 $^{14}C$ 측정 결과인 약 15,000년 전으로 해석하는 것이 합리적으로 생각된다.

OSL 연대측정을 통한 제주 고산리 유적의 형성과 점유시기 결정 (Evaluation of the formation and occupation of Gosan-ri archaeological site in Jeju Island using OSL dating)

  • 김명진
    • 분석과학
    • /
    • 제29권6호
    • /
    • pp.269-276
    • /
    • 2016
  • 고산리 유적은 우리나라 최초 토기로 알려진 고산리식 토기가 출토된 초기 신석기시대 유적이다. 이 연구에서는 고산리 유적의 형성 및 점유에 대한 절대연대 편년을 위하여 유적 내 표준 퇴적층에서 채취된 시료를 대상으로 OSL 연대측정을 수행하였다. 각 퇴적층의 고고선량은 $220^{\circ}C$ 열전처리 온도의 단일시료재현법을 적용하여 산출되었으며, 최종적으로 유적의 퇴적환경을 고려하여 maximum age model을 적용하여 결정하였다. 산출된 고고선량을 연간선량율로 나누어 고산리 유적 퇴적층의 OSL 연대를 결정하였다. 각 퇴적층의 OSL 연대와 14C 연대를 종합한 결과, 고산리 유적은 신석기인들에 의해 기원전 9천년 이후에 형성된 이후 고산리식 토기를 포함하는 신석기시대 초기 유적에서부터 다양한 시기의 다양한 유구가 존재해 오다가 기원전 4천년 중반에 폐기되어 현재에 이르렀다고 추론된다.

대학생이 이성교제 중 폭력과 대처행동 (College Students Dating Violence and Coping Behavior)

  • 김정란;김경신
    • 대한가정학회지
    • /
    • 제37권8호
    • /
    • pp.73-90
    • /
    • 1999
  • The purpose of this study was to find the general trends of college students'dating violence and coping behavior, to examine the difference among dating violence and coping behavior according to individual variables and relational variables, and to analyze the effects of these variables influencing coping behavior. The major findings were as follow; First, 99.1% of respondents reported that they had experienced violence at least once. The score of violence offense and violence victimization was lower than median. But male students' sexual violence was significantly higher than females'. Second, total score of coping behavior was lower than median. The score of female students positive coping was significantly higher than males, and that of mate students' avoidance coping was significantly higher than females. Third, the violence style varied with sex, altitude toward violence, anti-communication, and conflict. etc. Fourth, the positive coping behavior varied with victim response and victimization of physical violence. etc. The avoidance coping behavior varied with sex, age, grade, sex-role attitude, and partner's sexual violence. etc. ruth, the positive coping behavior was influenced by sex, partner's psychological violence, conflict, anti-communication. etc. The avoidance coping behavior was influenced by sex and grade.

  • PDF

Rules of Attraction: Females Perception of Male Self-Representation in a Dating App

  • Olga Roshchupkina;Olga Kim;Eun-Ju Lee
    • Asia Marketing Journal
    • /
    • 제24권4호
    • /
    • pp.169-177
    • /
    • 2023
  • In the current study, we explore how women decide whether to accept or reject a potential match offered by a dating app (Tinder). Specifically, we were trying to identify overlying factors that influence the decision and understand how women make a judgment based on limited cues provided by a Tinder profile. Women largely base their decision on the perceived attractiveness and character of the potential match. The findings suggest that attractiveness is highly subjective, with no universal rules that can be quantified; thus, it is hard to predict acceptance of the potential match. There are however factors that contribute significantly to profile rejection, such as a big age difference and the inability to clearly see the face of the person.

초음파를 이용한 14C 연대측정 토양시료의 부식산 추출법 개발 (Development of humic acid extraction method in soil and sediment using ultrasonic for 14C dating)

  • 박지연;홍완;박중헌
    • 분석과학
    • /
    • 제22권2호
    • /
    • pp.136-140
    • /
    • 2009
  • AMS (Accelerator Mass Spectrometry)를 이용한 방사성 탄소연대측정법으로 퇴적물 및 토양시료를 측정하기 위한 화학적 전처리법의 유기물 회수율을 개선하기 위하여, 초음파를 이용한 방법을 개발하였다. 일반적으로 널리 쓰이는 부식산 전처리법 중 단계 마다 사용되는 스터링법을 대신하여, 초음파 (ultrasonic)를 사용하고 초음파 출력, 반응 온도, 반응 시간 등 실험조건을 결정하였다. 유기물 함유량이 적어 연대측정이 불가능했던 시료에 대한 탄소 회수율이 6배 향상되어 다량의 시료를 얻기 힘든 연대측정분야에서는 매우 중요한 개선이 이루어졌다. 또한 동일 시료에 대해 초음파법과 스터링법으로 처리한 시료의 연대측정결과를 비교하여 초음파법이 회수율 향상 이외에는 연대측정결과에 영향을 미치지 않음을 확인하여 실용성이 있음을 증명하였다.