• 보존과학연구
• /
• s.23
• /
• 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.

• Journal of the Korean Chemical Society
• /
• v.14 no.1
• /
• pp.49-50
• /
• 1970

A wet oxidation method of oxalic acid standard used in radiocarbon dating is described, and error due to possible carbon isotope fractionation during the oxidation is estimated.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.4 no.3
• /
• pp.180-187
• /
• 1999

Radiocarbon dating method using benzene liquid scintillation was performed on the oyster shell fragments which producted from the shell mounts at Hadong Mogdori in Kyeongsangnamdo. This paper described to the age dating method and compared to the result. The carbon in sample is synthesized to a benzene through the sample preparation, $SrCO_3$, $SrC_2$, $C_2H_2$ and $C_6H_6$ synthesizing process. Age dating is calculated by Wallac 1415 Liquid Scintillation Counter. The result of age dating is estimated to be $4905{\pm}112$ yr BP in Yosu Univ. which is a good agreement with the result in Shimane Univ. ($4912{\pm}123$ yr BP). Radiocarbon dating method using benzene liquid scintillation is a simple and economical in operation and establishment, it has a potential instrumentation in the university and research institute.

• KOMUNHWA
• /
• no.52
• /
• pp.123-133
• /
• 1998

The extraction of carbon from temper in organic-tempered pottery of the Initial Neolithic sites on the Russian Far East allowed to date directly the earliest pottery in the area. First results show that pottery of the Gromatukha culture has $^{14}C$<

• Bulletin of the Korean Chemical Society
• /
• v.32 no.10
• /
• pp.3618-3623
• /
• 2011

This paper presents a stable isotope chemistry of bone collagen and carbonate. Bone carbonate has the potential to provide additional isotopic information. However, it remains controversial as to whether archaeological bone carbonate retains its original biogenic signature. I used a novel application of bone density fractionation and checked the integrity of ${\delta}^{13}C_{apa}$ values using radiocarbon dating. Diagenesis in archaeological bone carbonate still remains to be resolved in extracting biogenic information. The combined use of bone density fractionation and differential dissolution method shows a large shift in the ${\delta}^{13}C_{apa}$ values. Although ${\delta}^{13}C_{apa}$ values are improved in lighter density fractions, a large percentage of contamination in bone carbonate was reported via $^{14}C$ dating compared to that noted with bone collagen.

• The Korean Journal of Quaternary Research
• /
• v.20 no.1 s.26
• /
• pp.28-38
• /
• 2006

Since the radioactivity of U was discovered by Becquerel in 1896, a number of radiometric dating techniques based on radioactive decay have been developed with the help of precise and accurate instruments. Among them, radiocarbon dating was introduced as the most effective method in archeology in Korea. However, though the radiocarbon methods have contributed greatly to the development of archeology in Korea, it is limited to organics in a matrix of soil and sediment, including organic carbon, charcoal, bone and so on. If there are no organics in some paleolitic sites, other methods are required for dating. Therefore, we introduced OSL (Optically Stimulated Luminescence) dating method in this paper. The method is mainly based on quartz grains or other particles. The aim of this paper is to discuss about sampling method and the limitation of its application in archeology.

• Analytical Science and Technology
• /
• v.22 no.2
• /
• pp.136-140
• /
• 2009

To improve the carbon recovery yield of chemical pretreatment in soil and sediment for $^{14}C$ age dating using AMS (Accelerator Mass Spectrometry), we have developed ultrasonic method in chemical pretreatment to replace with stirring method which has been generally used in each step of humic acid extraction for soil and sediment samples. Extraction conditions such as ultrasonic power, temperature and reaction time have been optimized. Six times higher carbon recovery yield could be obtained from low carbon content samples using ultrasonic method. We also compared the dating results by AMS obtained using ultrasonic method with the ages of samples treated by the stirring method. It was found that this new method could be applied to the pretreatment process of low carbon content samples for AMS age dating without effects on the dated ages, and with highly improved carbon recovery yields.

• Journal of Korean Society for Atmospheric Environment
• /
• v.16 no.4
• /
• pp.421-428
• /
• 2000

Accelerator Mass Spectrometry (AMS) is presented for the applications to the environmental research. Traditionally the radiocarbon (14C) measurements have been made for the purpose of dating the archaeological and geological samples. 14C measurements using AMS however have become the more useful methods for the study of environmental science such as antropogenic modification of atmosphere and the determination of mixing ratios of fossil and biomass products. Such 14C AMS measurements have been extended to the discovery of new chemical tracers for investigations of sources of excessive contributions of CO2, CO, CH4 and other carbon-bearing molecules in the atmosphere.

• Fisheries and Aquatic Sciences
• /
• v.24 no.1
• /
• pp.53-62
• /
• 2021

Gindai (Pristipomoides zonatus) is one of six snappers in a management complex called the Deep 7 of the Hawaiian Islands. Little is known about its life history and a preliminary analysis of otolith thin sections indicated the species may exhibit moderate growth with a lifespan approaching 40 years. Preliminary age estimates from the previous study were reinvestigated using the same otolith sections in an attempt to validate those ages with bomb radiocarbon (¹⁴C) dating. From the misalignment of birth years for the otolith ¹⁴C measurements with regional references - the post-peak bomb ¹⁴C decline period - it was concluded that previous ages were inflated from overcounting of the earliest growth zone structure in otolith sections. The oldest gindai was re-aged to 26 years once the age reading was adjusted for early overcounting, 13 years younger than the original estimate of 39 years for this fish. In general, the earliest otolith growth of gindai was massive and complicated by numerous subannual checks. The approach of lumping the early growth structures was supported by the alignment of ¹⁴C measurements from otolith core material (first year of growth). The result was greater consistency of calculated birthdates with the ¹⁴C decline reference, along with minor offsets that may indicate age estimation was imprecise by a few years for some individuals. The revised von Bertalanffy growth function applied to the validated age-at-length estimates revealed more rapid growth (k = 0.378 cf. 0.113) and a lifespan of approximately 30 years. The findings presented here are a case study of how the bomb ¹⁴C decline period can be used as a tool in the refinement of age reading protocols.

• Analytical Science and Technology
• /
• v.29 no.6
• /
• pp.269-276
• /
• 2016

Gosan-ri site is known as the early Neolithic cultural heritage, in which an archaic plainware, called as the Gosan-ri-type pottery, was excavated regarding as the first pottery manufactured in Korea. In this study, OSL dating was carried out to five soil layer samples collected in stratigraphic cross-section for evaluating the formation and occupation of the Gosan-ri site. Paleodose of each soil sample was calculated using the single aliquot regenerative dose (SAR) method with preheat of $220^{\circ}C$ and finally determined using maximum age model, considering its deposition process. The OSL age was determined from the ratio of paleodose to annual dose rate. From the resultant OSL ages and the related 14C dates, it was concluded that the Gosan-ri site was formed after 9,000 BC and a variety of cultural feature including the Gosan-ri-type pottery were occupied ranging from the early Neolithic to the middle of 4,000 BC. Finally, the Gosan-ri site was discarded in the middle of 4,000 BC and has been arrived at present through natural deposits.