• The Journal of the Petrological Society of Korea
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• v.4 no.2
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• pp.124-133
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• 1995

Oxygen isotope compositions have been determined for the granitic and the related rocks from the Wolf River Ratholith, Wisconsin in U.S.A. Plutons which belong to the differentiation trend are almost identical in oxygen isotope fractionation, and plutons of undifferential sequences also show oxygen isotope compositions similar to each other, which show little isotope fractionations at high temperature range. In oxygen osotope composition, the country rocks (the Penokean plutonic rocks), which is higher by 1~2 permil than the batholith are improbable source of the batholith. However, the assimilation of parent magma of lower ${\delta}^{18}O$ values than the batholith with the Penokean plutonic rocks might have produced the batholith.

• The Korean Journal of Malacology
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• v.30 no.1
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• pp.1-8
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• 2014

Oxygen isotope analysis was carried out on a oyster (Crassostrea gigas) from the neolithic age Gagok-ri shell midden site, Dangjin, Korea to determine the seasonality of shellfish gathering and site occupation. Isotope samples were taken from the hinge section of the left valve of the oyster. The isotope values of the shell range from -2.02‰ to -6.05‰ vs PDB. The isotope profile shows a seasonal temperature cycle, providing information related to seasonality of shellfish gathering. The isotope values towards the edge of the hinge are gradually increasing, suggesting progressively cooling and a fall period of shell gathering and site occupation. The result shows that the oxygen isotope analysis using oyster shell hinges can be used for archaeological seasonality studies.

• Membrane Journal
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• v.13 no.3
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• pp.154-161
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• 2003

We measured the permeation characteristics of water with the hydrophobic PTFE membranes dependent on water temperature to confirm the separation of oxygen isotopes using Air Gap Membrane Distillation (AGMD) and Vacuum Enhanced Membrane Distillation (VEMD). Isotopic concentrations of $H_2^{16}O$ and $H_2^{18}O$ of the permeated water vapor were measured by Diode Laser Absorption Spectroscopy. Concentrations of the heavy oxygen isotopes in the permeated water vapor were decreased. Isotope separation coefficients for the hydrophobic PTFE membranes were 1.004∼1.01 depending on the experimental conditions. We observed the effects of air in membrane pores on the oxygen isotope separation. Isotope separation coefficients for the hydrophobic PTFE membranes without air in pores are higher than those for the membrane with air in pores.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.133-136
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• 2002

제주도에 내리는 강수의 동위원소 조성의 시공간적인 분포를 파악하고 지하수 함양과의 관련성을 연구하기 위하여, 한라산의 남측과 북측 사면에 8개의 강수채수기를 설치하여 1년 동안 (2000. 9 ~ 2001. 8) 월강수를 채취하였다. 연구기간 동안에 강수량은 남쪽사면이 북쪽사면보다 약 37% 더 많았다. 강수의 산소동위원소 조성은 온도효과를 거의 보이지 않았다. 그러나 여름 강우에는 우량효과가 매우 뚜렷하였다. 고도가 높아지면서 강수의 동위원소 조성이 낮아지는 고도효과가 남측과 북측사면에서 모두 뚜렷이 관찰되었다. 가중평균값으로 볼 때 북측사면 강수의 동위원소 조성이 남측사면 강수보다 약 0.5$^{0}$ $_{00}$ 낮은 것이 관찰되었는데 이는 비그늘효과(rain shadow effect) 때문인 것으로 해석된다. 다른 지역에 비하여 북부지역 지하수 동위원소 조성이 상대적으로 결핍되어 있는 것은 기존 연구 결과처럼 지하수 이동속도가 빠르기 때문에 일어나는 현상이 아니고 지하수로 함양된 강수의 원래의 동위원소 조성을 반영하기 때문인 것으로 해석된다.다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.360-364
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• 2006

물수지 분석을 통해서 유역의 수문순화 체계를 이해하기 위해서는 무엇보다 필요한 인자가 증발산량이다. 장기간에 걸쳐 연구유역에서 수소와 산소 동위원소를 이용하여 증발산량을 산정하였다. 물 분자를 이루는 이상적인 추적자인 수소와 산소 강우를 풍수기($4{\sim}10$월)와 갈수기(11월$\sim$3월)로 나누어 수소와 산소 동위원소 조성을 강수량 가중 평균치를 구하고 이 값을 지하수의 수소와 산소 동위원소 조성 값과 비교하여 증발산량을 산정한 것이다. 이러한 시도는 증발산량의 산정이 단순한 경험식이나 열전도 가정식이 아닌 실측했다는데 의의가 있다.

• The Journal of Engineering Geology
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• v.12 no.3
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• pp.285-294
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• 2002

The origin of nitrate in confined groundwater was studied using oxygen ($\delta$180), hydrogen ($\delta$D), and nitrogen ($\delta$15N) stable isotopes, along with chemical data of NO3-N. We analyzed groundwaters from more than sixty manufactories producing natural mineral waters around the country During the period of 1998-2001, an average value of nitrate was fair]y low (0.95 mg/$\ell$), however, groundwaters from six sites showed more than 2 mg/$\ell$ of nitrate. The stable isotope data of the groundwaters are -8.3~-11 $\textperthousand$ $\delta$8O, -60~-75 $\textperthousand$ $\delta$D, which lies in an average range of the groundwaters. The nitrogen isotope data with -11.8~-5.1$\textperthousand$ $\delta$15N suggest that manure, organic nitrate, and fertilizers can not be the origin of nitrate in the goundwaters.

• Ocean and Polar Research
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• v.30 no.3
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• pp.249-258
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• 2008

Oxygen isotopic composition(${\delta}^{18}O$) of walleye pollock, Theragra chalcogramma, otoliths were measured to investigate interannual and regional correlation with habitat temperature. Specimens were collected from fishermen in Korea and Japan between $1997{\sim}1999$, while seawater temperatures were obtained from Korean and Japanese Oceanographic Data Centers. Seawater temperature was generally lower off the eastern Korean Peninsula than off eastern Hokkaido(Japan). Sagittal otoliths were removed for measurement of ${\delta}^{18}O$ using a micro-drilling technique. In most cases, ${\delta}^{18}O$ and habitat temperature exhibited negative relationship in Korean and Japanese waters. Higher ${\delta}^{18}O$ was observed in Korean pollock compared to Japanese pollock. The marginal parts of otoliths exhibited higher ${\delta}^{18}O$ than cores from both regions. This is an indication that somatic growth of walleye pollock occurs in deeper and cooler waters. Interannual variation in ${\delta}^{18}O$ was also observed. Mean ${\delta}^{18}O$ values acquired from 1997 otoliths were lower(2.15%) than those of 1998(2.67%) and 1999 (2.65%) in Korean pollock. These measurements coincided with changes in observed temperature in Korean waters, in which mean seawater temperature was warmer in 1997 than in 1998 and 1999. In Japanese waters, mean seawater temperature was lowest in 1997, which coincided with highest ${\delta}^{18}O$ values in the same year.

• Economic and Environmental Geology
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• v.50 no.6
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• pp.517-523
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• 2017

A linear relationship between two stable water isotopes, oxygen and hydrogen, has been used to understand the water cycle as a basic tool. A slope and intercept from the linear relationship indicates what kind of physical processes occur during movement of water. Traditionally, ordinary least squares (OLS) method has been utilized for the linear relationship, but total least squares (TLS) method provides more accurate slope and intercept theoretically because isotopic compositions of both oxygen and hydrogen have uncertainties. In this work, OLS and TLS were compared with isotopic compositions of snow and snowmelt collected from the King Sejong Station, Antarctica and isotopic compositions of water vapor observed by Lee et al. (2013) in the western part of Korea. The slopes from the linear relationship of isotopic compositions of snow and snowmelt at the King Sejong Station were estimated to be 7.00 (OLS) and 7.16(TLS) and the slopes of stable water vapor isotopes were 7.75(OLS) and 7.87(TLS). There was a melting process in the snow near the King Sejong Station and the water vapor was directly transported from the ocean to the study area based on the slope calculations. There is no significant difference in two slopes to interpret the physical processes. However, it is necessary to evaluate the slope differences from the two methods for studies for example, groundwater recharge processes, using the absolute slope values.

• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.297-311
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• 1997

To understand the mass-independent isotopic fractionation effects, thermal decomposition of ozone was performed. Initial oxygen gas was converted to ozone completely. Then, the ozone was decomposed to oxygen at various temperatures ($30~150^{\circ}C$). Isotopic compositions of product oxygen and residual ozone were measured using a stable isotope mass spectrometer. The experimental results were compared with the studies which were performed at the similar conditions. From the raw experimental data, the functions of the instantaneous fractionation factors were calculated by the least square fit. The results clearly showed the temperature dependence. They also showed the pressure dependence and the surface effect. This study may play an important role in the study of ozone decomposition mechanism. It can be applied to explain the mass-independent isotopic pattern found in stratospheric ozone and in meteorites.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.231-234
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• 2003

Using lysimeter, oxygen and hydrogen isotopic compositions of soil waters were monitored at a test site of Jeju university during November 2002 to June 2003. Oxygen and hydrogen isotopic compositions of soil waters were found to reflect those of precipitation of the study area. Based on d-values, apparent residence times of about 2 and 4 months were found for infiltration of water through the soil layer to depths of 30 cm and 60cm, respectively.