• Korean Journal of Heritage: History & Science
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• v.46 no.4
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• pp.108-125
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• 2013

This study examined the actual reconstruction drawing, composite mineral, particle size and property test, fine organic matters, color differences and main ingredients of the earthen mold excavated in Dongcheon-dong, Gyungju. The cross-section of the inner mold and outer mold divides into inside (1st layer) and outside (2nd layer), with organic matters mixed outside. The cross-section has been altered due to heat and form removal agent. X-ray analysis revealed that the layer was made of minerals with high transmissivity and only quartz particles were observed through a polarizing microscope. The inside of cross-section in SEM observation identified enlarged air gap, with crack developed in the center, but no changes observed on the outside. The particle size of the composites is almost the same for the inner mold and outer mold and is silt clay loam. The ratio between silt clay and silt clay loam was about 2.7:1 and 2.9:1 respectively. In the property test, the density and absorption rate of inner mold and outer mold were similar, but porosity was different, with inner mold of 27.36% and outer mold of 31.09%. The color difference of cross-section seems to have been caused by the spread of soot on the 1st layer surface for removal of form or by the covering of ink to protect the 1st layer. Composite mineral analysis revealed the same composition for the inner mold and outer mold, except for the magnetite that was detected in the inner mold alone. As for the main ingredient analysis, the average content of $SiO_2$ was 71.64% and that of $Al_2O_3$ was 14.59%. As for the sub-ingredients, $Fe_2O_3$ was 4.51%, $K_2O$ 3.06%, $Na_2O$, MgO, CaO, $TiO_2$, $P_2O_5$ and MnO was less than 2%.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.2
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• pp.103-109
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• 2009

Soils originated from limestone, located at the southern part of Kangwon province and Jecheon, Danyang of Chungbuk province are mainly composed of fine texture, and have different properties from soils originated from granite and granite gneiss, especially for water movement. This study was conducted for classification of hydrologic soil group (HSG) of soils originated from limestone by measuring the infiltration rate of surface soils and percolation rate of sub soils. Soils used for the experiment were 6 soils in total : Gwarim, Mosan, Jangseong, Maji, Anmi and Pyongan series. Infiltration and percolation rate were measured by a disc tension infiltrometer and a Guelph permeameter, respectively. Particle size distribution and organic matter content of the soils were analyzed. HSG, which was made by USDA NRCS(National Resources Conservation Service) for hydrology, of Gwarim series with O horizon of accumulated organic matter was classified as type A which show the properties of low runoff potential, rapid infiltration and percolation rate. HSG of Mosan series, which has high gravel content and very rapid permeability, was classified as type B/D because of the impermaeble base rock layer under 50cm from surface. HSG of Jangseong series with shallow soil depth was classified as type C/D owing to the impermaeble base rock layer under 50cm from surface. HSG of Maji series was type B, and HSG of Anmi series used as paddy land was type D because of slow infiltration and percolation rate caused by the disturbance of surface soil by puddling. HSG of Pyeongan series having a sudden change of layer in soil texture was type D because of the slow percolation rate caused a the layer.

• Korean Journal of Heritage: History & Science
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• v.50 no.4
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• pp.148-165
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• 2017

Mural paintings drawn inside ancient tombs are very sensitive to changes in the environment such as temperature and humidity, especially the finish layer of the tomb murals differ in preservability depending on the material properties and humidity conditions. In this study, I examined the mural painting of Songsan-ri Tomb No.6, where the finish layer was made of earth, and identified the physical changes that can occur due to drying, depending on the material properties of the finish layer. I found out through particle size analysis that the finish layer of the mural painting in Songsan-ri Tomb No.6 is about 85.0wt% below silt, about 14.0wt% clay therein, mostly composed of silt and below clay. I also found out through physical property evaluation that surface change rate of samples showed the largest change at 15.5% in reproduced finish layer sample made up of bentonite, followed by 7.8% of reproduced finish layer sample made up of celadon soil, 6.3% of reproduced finish layer sample made up of loess, 6.2% of reproduced finish layer sample composed of white clay and the same order of change in appearance was confirmed in each sample consisted of soil. In addition, it showed the same trend of surface change rate, and the bentonite condition showed the largest change, in the measurement of shrinkage rate and expansion rate. The experiment shows that the finish layer composed of soil is affected by cohesion among particles according to the content of fine parts and the relationship between the agglomeration due to the content of the differentiated part and the stress due to the expansibility depending on the kind of the clay mineral etc. Therefore, it can be concluded that the physical damage occurred in the mural painting finish layer of the Songsan-ri Tomb No.6 is related to the factors such as the material characteristics of the soil and the highly humid environmental change inside the tomb.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.385-392
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• 2009

This study was conducted to reclassify Namweon series, black volcanic ash soils, in Jeju Island based on the second edition of Soil Taxonomy : A Basic System of Soil Classification for Making and Interpreting Soil Surveys. Morphological properties of typifying pedon of Namweon series were investigated and physicochemical properties were analyzed according to Soil Survey Laboratory Methods Manual. The typifying pedon of Namweon series has black (10YR 2/1) silt loam Ap horizon (0~11 cm) and black (10YR 2/1) silt loam BA horizon (11~72 cm). Bw horizon (72~100 cm) is very dark brown (10YR 2/2) silt loam. That occurs on lava plain derived from volcanic ash materials. The typifying pedon contains 5.2~6.4% oxalate extractable (Al + 1/2 Fe), over 85% phosphate retention, and lower bulk density than $0.90Mg\;m^{-3}$. Ap, BA, and Bw horizons of the pedon have andic soil properties. That can be classified as Andisol. The typifying pedon has an udic soil moisture regime and has a 1,500 kPa water retention of 15% or more on air-dried samples throughout all horizons, and can be classified as Udand. Ap and BA horizons (0~72 cm) have a color value, moist, and chroma of 2 or less, melanic index of 1.70 or less, and 6% or more organic carbon. That meets the requirements of melanic epipedon. That keys out as Melanudand. That has more than 6.0% organic carbon and the colors of mollic epipedon throughout a layer 50 cm or more thick within 60 cm of the mineral soil surface.. Thus, that keys out as Pachic Melanudand. The pedon has a fine-earth fraction that has a water content at 1,500 kPa tension of 12% or more on air-dried samples and has less than 35% (by volume) rock fragments. Thus, the substitute for particle-size class is medial. That has a sum of 8 times the Si (percnt by weight extracted by acid oxalate) plus 2 times the Fe (percnt by weight extracted by acid oxalate) of 5 or more, and 2 times the Fe is more than 8 times the Si. Thus, the mineralogy class is ferrihydritic. Namweon series can be classified as medial, ferrihydritic, thermic family of Pachic Melanudands, not as ashy, thermic family of Typic Melanudands.