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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korean earth science society
Journal Basic Information
Journal DOI :
The Korean Earth Science Society
Editor in Chief :
Volume & Issues
Volume 30, Issue 7 - Dec 2009
Volume 30, Issue 6 - Oct 2009
Volume 30, Issue 5 - Sep 2009
Volume 30, Issue 4 - Aug 2009
Volume 30, Issue 3 - Jun 2009
Volume 30, Issue 2 - Apr 2009
Volume 30, Issue 1 - Feb 2009
Selecting the target year
Variation Analysis of Geomagnetic Data Observed Around the Event of Andong Earthquake (May 2, 2009)
Oh, Seok-Hoon ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 683~691
DOI : 10.5467/JKESS.2009.30.6.683
Geomagnetic variation around May 2, 2009 when Angdong earthquake broke out was analyzed using the data recorded at the Cheong-yang geomagnetic observatory, KMA. Firstly, we predict the geomagnetic variation by PCA analysis of geomagnetic data, and then compare the predicted value with the observed data to find any significant differences in residuals. Secondly, wavelet semblance technique is applied to compare the time series before and after the earthquake. Some meaningful change is detected in the Z-field. Thirdly, eigen value analysis for the 3 component geomagnetic data is performed. The location of the observatory was too far from the epicenter and the magnitude was too small to find decisive precursory phenomenon. Nevertheless we can detect some significant correlation between the earthquake and the variation of the geomagnetic field. Various signal processing methods applied in this study will give some opportunity to find precursory effects in the future.
Wavelet-based Semblance Filtering of Geophysical Data and Its Application
Oh, Seok-Hoon ; Suh, Baek-Soo ; Im, Eun-Sang ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 692~698
DOI : 10.5467/JKESS.2009.30.6.692
Wavelet transform has been widely used in terms that it may overcome the shortcoming of conventional Fourier transform. Fourier transform has its difficulty to explain how the transformed domain, frequency, is related with time. Traditional semblance technique in Fourier transform was devised to compare two time series on the basis of their phase as a function of frequency. But this method is known not to work well for the non-stationary signal. In this study, we present two applications of the wavelet-based semblance method to geophysical data. Firstly, we show filtered geomagnetic signal remained with components of high correlation to each observatory. Secondly, highly correlated residual signal of gravity and magnetic survey data, which are also filtered by this semblance method, is present.
3-D Inversion of 3-D Synthetic DC Resistivity Data for Vein-type Ore Deposits
Lee, Ho-Yong ; Jung, Hyun-Key ; Jeong, Woo-Don ; Kwak, Na-Eun ; Lee, Hyo-Sun ; Min, Dong-Joo ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 699~708
DOI : 10.5467/JKESS.2009.30.6.699
Recently as the interest in the development of domestic ore deposits has increased, we can easily find some studies on exploration geophysics-based ore-deposit survey in literature. Based on the fact that mineralized zone are generally more conductive than surrounding media, electrical resistivity survey among several geophysical surveys has been applied to investigate metallic ore deposits. Most of them are grounded on 2-D survey. However, 2-D inversion may lead to some misinterpretation for 3-D geological structures. In this study, we investigate the feasibility of the 3-D electrical resistivity survey to 3-D vein-type ore deposits. We first simulate 2-D dipole-dipole survey data for survey lines normal to the strike and 3-D pole-pole survey data, and then perform 3-D inversion. For 3-D ore-body structures, we assume a width-varying dyke, a wedge-shaped, and a fault model. The 3-D inversion results are compared to 2-D inversion results. By comparing 3-D inversion results for 2-D dipole-dipole survey data to 3-D inversion results for 3-D pole-pole survey data, we could note that the 2-D dipole-dipole survey data yield better inversion results than the 3-D pole-pole data, which is due to the main characteristic of the pole-pole array. From these results, we are convinced that if we have certain information on the direction of the strike, it would be desirable to apply 2-D dipole-diple survey for the survey lines normal to the strike. However, in most cases, we do not have any information on the direction of the strike, because we already developed the ore deposit with the outcrops and the remaining ore deposits are buried under the surface. In that case, performing 3-D pole-pole electrical resistivity survey would be a reasonable choice to obtain more accurate interpretation on ore body structure in spite of low resolution of pole-pole array.
The Analysis of Mesoscale Circulations Characteristics Caused by the Evaporation-Efficiency of Water Retention Pavement
Kim, In-Su ; Lee, Soon-Hwan ; Kim, Hae-Dong ; Suh, Young-Chan ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 709~720
DOI : 10.5467/JKESS.2009.30.6.709
Field observation and numerical experiments were conducted to understand the impact of water retention pavement on the surface heat budget and on the regional circulation. The numerical model applied in this study is the atmospheric dynamic model Local Circulation Model (LCM) with two dimensional grid system, and a field observation was carried out under the clear sky and calm conditions of the weather on 19 July 2007. In the field observation, the maximum value of surface temperature on pavement covered with water retention material reached the
at 1430 LST and the values was lower for
than that of asphalt without the material. The Case BET03 assumed to be 0.3 for the surface evaporation efficiency was in good agreement with the observation and its sensible and latent heat fluxes were numerically estimated to be 229 and 227
, respectively. Results of the numerical experiments demonstrated that the water retention pavement tends to induce the increase of latent heat flux associated with the lower surface temperature and mixing height during the daytime. Discontinuity of latent heat caused by the water retention pavement also tends to promote the development of mesoscale circulation called as land-land breeze or country breeze.
A Study on the Characteristics of Tropical Cyclone Passage Frequency over the Western North Pacific using Empirical Orthogonal Function
Choi, Ki-Seon ; Kang, Ki-Ryong ; Kim, Do-Woo ; Hwang, Ho-Seong ; Lee, Sang-Ryong ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 721~733
DOI : 10.5467/JKESS.2009.30.6.721
A pattern of tropical cyclone (TC) movement in the western North Pacific area was studied using the empirical orthogonal function (EOF) and the best track data from 1951 to 2007. The independent variable used in this study was defined as the frequency of tropical cyclone passage in 5 by 5 degree grid. The
modes were the east-west, north-south and diagonal variation patterns. Based on the time series of each component, the signs of first and second mode changed in 1997 and 1991, respectively, which seems to be related to the fact that the passage frequency was higher in the South China Sea for 20 years before 1990s, and recent 20 years in the East Asian area. When the eigen vectors were negative values in the first and second modes and TC moves into the western North Pacific, TC was formed mainly at the east side relatively compared to the case of the positive eigen vectors. The first mode seems to relate to the pressure pattern at the south of Lake Baikal, the second mode the variation pattern around
, and the third mode the pressure pattern around Japan. The first mode was also closely related to the ENSO and negatively related to the
-3.4 index in the correlation analysis with SST anomalies.
The Spectral Characteristics of Climatological Variables over the Asian Dust Source Regions and its Association with Particle Concentrations in Busan
Son, Hye-Young ; Kim, Cheol-Hee ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 734~743
DOI : 10.5467/JKESS.2009.30.6.734
In order to examine how climatological condition can influence on urban scale particulate air pollutants, single and cross spectrum analysis have been performed to daily mean concentrations of particulate matters (
) in Busan together with the climatological variables over the Asian dust source regions. Single power spectrum analysis of
concentrations in Busan shows that, aside from the typical and well-known periodicities, 3-4 year of peak periodicity of power spectrum density was identified. In cross spectrum analysis, this 3-4 year periodicity is found to have a strong positive correlation with the wind speed and pressure, and negative with the temperature and relative humidity, which is rather consistent with both characteristics of air mass during the Asian dust event whose periodicities have been recorded inter-annually over the Korean urban cities. Over the Asian dust source regions,
vs. precipitation shows no significant periodicity from the time series of precipitation data, but the periodicity of EDI (Effective Drought Index) shows some interannual variabilities ranging from 2 to 4 years over the various source regions, suggesting that, rather than precipitation itself, the EDI could be more closely associated with the occurrence frequency of Asian dust and interannual variability of urban particle concentrations in Korean cities.
Characteristics of Brightness Temperature of Geostationary Satellite on Lightning Events during Summer over South Korea
Lee, Yun-Jeong ; Suh, Myoung-Seok ; Eom, Hyo-Sik ; Seo, Eun-Kyoung ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 744~758
DOI : 10.5467/JKESS.2009.30.6.744
The characteristics of brightness temperature (BT) of infrared and water vapor channels from MTSAT-1R have been investigated using 12 persistent and frequent lightning cases selected from the summer lightnings of 2006-2008. The infrared (IR1, 10.3-11.3
) and water vapor (WV, 6.5-7.0
) channels from the MTSAT-1R and the lightning observation data from Korea Meteorological Administration are used. When there is no lightning, the BTs of the IR1 and WV channels show the largest frequency at around 290-295K and 245K, respectively. On the other hand, the BTs of two channels show the largest frequency at 215K caused by strong convection when there is lightning. As a result, the WV-IR1 difference (BTDWI) sharply increases from -50K to 0K. Although it depends on the evolution stage of thunderstorms, the lightning mainly occurs at the core of circular convection in the mesoscale convective complex (MCC), whereas the lightning occurs by concentrated line-shape in the squall line. A strong positive correlation exists between the lightning frequency and the BT in the MCC regardless of the BT, but only at the very cold BT in the squall line. In general, the characteristics of BT are well defined for the lightning occurring in the concentrated line, but they are not well defined in the MCC, especially during the decaying stage of MCC. When they are defined well, the lightning occurs when the BTs of IR1 and WV are lower than 215K, BTDWI is near -3 to 1K, and local standard deviation of IR1 decreases to around 1K.
Characteristics of 8th Grade Students' Conclusions Presented in Self-Directed Scientific Inquiry Reports
Shin, Mi-Young ; Choe, Seung-Urn ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 759~772
DOI : 10.5467/JKESS.2009.30.6.759
The purpose of this study was to understand characteristics of eighth graders' conclusions presented in their self-directed scientific inquiry reports. We developed a framework, Analysis of Conclusions of Self-Directed Scientific Inquiry, to analyze students' conclusions. We then compared the conclusions with the inquiry questions students generated to find out whether the questions affected students' conclusions. In addition, we analyzed students' responses from the survey about their perceptions of drawing conclusions. According to the results, the conclusions were characterized into two categories, i.e., scientific basic assumption and scientific explanation. Almost half of the students' conclusions fall under the scientific basic assumptions. Most of the scientific explanations were deductive explanations and inductive explanations. Then, the kinds of conclusions were affected by the inquiry questions because the scientific explanations were made more than the scientific basic assumptions in answering the inquiry questions. Some students couldn't recognize differences between conclusions and experiment results.
Levels of Reflection and Attainment of School Science Curriculum Demonstrated in the Texts of Exhibition Panels in Science Museums: Case Studies of Earth Science Contents at the Secondary Level
Kim, Tae-Hyeong ; Lee, Chang-Zin ; Ryu, Chun-Ryol ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 773~786
DOI : 10.5467/JKESS.2009.30.6.773
Recently, the connection between science museum and school science curriculum has been emphasized, but the frameworks for evaluating school science curricula are insufficient in terms of how much of school science curriculum was reflected and attained. The purposes of this study are to develop a framework that can be utilized to evaluate levels of curriculum that are reflected and attained in the texts of exhibition panels displayed in science museums. We developed an evaluation tool based on the frameworks used to assess students' achievement in the secondary school curriculum, and we used the tool to measure the reflection and attainment levels demonstrated in the texts of exhibition panels about earth science contents of secondary school curriculum in three science museums located in Chungcheong-do, central part of Korea. Findings showed that the levels of reflection and attainment of secondary school curriculum in exhibition panels about earth science contents in science museums were measured 38.7% and 2.82 points out of 5.0respectively. We hope that the evaluation tool used in this study could be utilized to measure the levels of reflection and attainment of secondary school science curriculum demonstrated in the text of each of exhibition panels in science museums.
Development of Experimental Apparatus to Efficiently Educate the Phenomena by Coriolis Force
Kim, Eun-Ju ; Lee, Sang-Bub ; Yoon, Ill-Hee ; Lee, Hyo-Nyong ;
Journal of the Korean earth science society, volume 30, issue 6, 2009, Pages 787~798
DOI : 10.5467/JKESS.2009.30.6.787
A new apparatus was presented in order to help understand the concept of the Coriolis force which is essential in understanding the trajectories of the atmospheric current and the tide of seawater. In the apparatus proposed in high-school textbooks, since the slide from which the ball is released is set outside the rotating disk, it was not possible to interpret, with the trajectory of the ball on the disk, the motion of the atmosphere and the current of seawater occurring as a result of the Coriolis force. In order to resolve such problem, a new apparatus was developed in which the slide was set on the disk and rotated with the disk. Experiments were carried out using both the existing apparatus and the new apparatus, and the results were compared. While, in the experiment performed with the existing apparatus, it was difficult to analyze the trajectory of ball because the motion of the ball was not smooth when it hit the disk, in the experiment with the new apparatus it was much easier to analyze the trajectories. It was also possible to compare the trajectories when the initial velocity of the ball was varied.