• Journal of The Geomorphological Association of Korea
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• v.23 no.3
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• pp.41-55
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• 2016

The granulometric characteristics and chemical composition of the samples from the Bukpyeong myeon, Hainam gun, Jeollanam do were analyzed in this study. The samples were collected from the outcrop of coastal area where the height is about 30m. The burial age of the sediments also estimated by OSL(Optically Stimulated Luminescence) method. The origin and forming processes of the samples are not clear in this stage as limited number of evidences can be found. However it is suggested that the samples are not aeolian deposits originated from chinese loess by the chemical analysis. The mean diameter of samples were $5{\sim}6{\varphi}(silt)$ and are increased slightly downwards. The samples also well sorted. The samples have been heavily weathered by the chemical alteration index. The value of CIA increase downward rapidly at the upper part of outcrop, then stabilized afterwards. The vertical concentration changes ratio of cations varies; Si increases downwards while Fe, Ti, K and Mg decrease. There are fluctuation in concentration ratio of Na and Ca with increasing depth. The burial age of sample from upper part are estimated as $104.52{\pm}4.45ka\;BP$, while that of lower part are $136.10{\pm}6.52ka\;BP$, and they fall in to last part of MS6. The deposition rate for this site is found about 0.017mm/year. The uplift rate of the site is supposed to be 0.24~0.26m/ka with assumption of palaeo-sea level of +6m. However the origin of the sediment deposits should be explored and cleared.

• Korean Journal of Heritage: History & Science
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• v.45 no.1
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• pp.86-101
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• 2012

The constituting rocks of Multi-storied Round shape stone Pagoda of Unjusa Temple are lithic tuff and rhyolite tuff breaccia which show green or grey and also rock fragment with poor roundness are present in the structure. lithic tuff is composed of feldspar and quartz which are glassy texture and cryptocrystalline and also micro crystalline are scattered. phenocryst quartz and feldspar in the substrate composed of feldspar and opaque minerals are found in rhyolite tuff breaccia. dust, exfoliation, cavity, fracture and crack are observed in all the stone of the pagoda and the result of Infrared Thermography shows partial inter cavities have developed severely which may cause further exfoliation. In addition, a great deal of various grey, green, and yellow brown lichen as well as bryophyte are present at the upper part of eastern and western roof stone located above the third floor. Discolors remarkably shown at stereobate and roof stone are identified as inorganic pollutants such as manganese oxide, iron oxide and iron hydroxide. The stone of the pagoda of the Chemical Index of Alteration (CIA) and the Weathering Potential Index (WPI) are 55.69 and 1.12 respectively and this corresponds to a highly weathered stage. The measured values, average ultrasonic velocity 2,892m/s, coefficient of weathering 0.4k and compressive strength $1,096kg/cm^3$, suggest that the rock strength and durability are weakened.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.23-36
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• 2012

This study aims to think about the problem of dolmens: the reasons for the presence of dolmens and how to construct it, at the point of view of geographical and geomorphological. The subjects of this study is the dolmens which locate between at Dogok Hyosanri and Chunyang Daesinri Hwasoon-gun, Jeonlanamdo. The study areas in Hyosanri, Daesinri has been observed as follows. First, the long axis direction of Dolmen upper stone and the slope one are the same. Second, tor, block stream, hockey stick, etc. Third, Composition of the soil silt> sand> clay is distributed in the order. Forth, The soil of high quality silt and the roundness of angular, sub-angular-level and the high frequency, peaks of quarts and illite clay minerals show. Fifth, in the result of $SiO_2/Al_2O_3$, $SiO_2/R_2O_3$, and CIA(Chemical Index of Alteration), Hyosanri, Daesinri areas show mechanical weathering was dominant and chemical weathering environment was not being progressed. The blocks used in construction of dolmens had moved to the bottom of slopes by mass movement such as solifluction then them which had been placed in the position seem to be used by people of Bronze. Based on the above results, the process of construction of dolmens can be estimated as follows. They would dig up the ground under the upper stone of dolmens, put the supporting stone in the place, then dig up earth, place into remains, close the obturating stones, then heal up earth.

• Journal of the Korean earth science society
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• v.33 no.6
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• pp.481-496
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• 2012

REE, major and trace elements, and Sr-Nd isotopic ratios of surface sediments around Jeju Island were analyzed for identifying the origin of the sediments. The Chemical Index of Alteration (CIA) between 44.2 to 68.9 (av. 59.4) shows a similarity with the Huanghe sediment. The most sediments found within the study areas show a very similar chondrite-normalized REE pattern that has enriched LREE ($La_{(N)}/Sm_{(N)}$ >3) and small negative Eu anomaly, typically of average shales. The UCC-nornalized REE patterns of the southwestern offshore sediment samples show a very similar pattem with the Changjiang sediment with enriched in most REE and more convex REE pattern than those of the Huanghe and Keum rivers sediments, which indicates that the Changjiang River's suspended sediments have been transported into the western part of Jeju Island. The $^{87}Sr/^{86}Sr$ isotopic ratios vs ${\varepsilon}_{Nd}(0)$ values were thus used as a tracer to discriminate the provenance of sediments in the study area. Based on the discriminated diagram, it clearly showed that most sediments in the western and northwestern part were closely plotted with sediments of the Huanghe River. However, the sediments in the southwestern part near the Changjianf estuary were closely plotted with submerged delta sediments of the Changjiang River. In contrast, the sediment samples of the northeastern part showed discriminative figures from those of the Chinese rivers. It suggests that sediments around Jeju Island must be originated from diverse sources.

• Korean Journal of Heritage: History & Science
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• v.37
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• pp.285-307
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• 2004

Synthesize and examine petrological characteristic and geochemical characteristic by weathering formation of rock and progress of weathering laying stress on stone cultural properties of Unjusa temple of Chonnam Hwasun county site in this research. Examine closely weathering element that influence mechanical, chemical, mineralogical and physical weathering of rocks that accomplish stone cultural properties and these do quantification, wish to utilize by a basic knowledge for conservation scientific research of stone cultural properties by these result. Enforced component analysis of rock and mineralogical survey about 18 samples (pyroclastic tuff; 7, ash tuff; 4, granite ; 4, granitic gneiss; 3) all to search petrological characteristic and geochemical characteristic by weathering of Unjusa temple precinct stone cultural properties and recorded deterioration degree about each stone cultural properties observing naked eye. Major rock that constitution Unjusa temple one great geological features has strike of N30-40W and dip of 10-20NE being pyroclastic tuff. This pyroclastic tuff is ranging very extensively laying center on Unjusa temple and stone cultural properties of precinct is modeled by this pyroclastic tuff. Stone cultural propertieses of present Unjusa temple precinct are accomplishing structural imbalance with serious crack, and because weathering of rock with serious biological pollution is gone fairly, rubble break away and weathering and deterioration phenomenon such as fall off of a particle of mineral are appearing extremely. Also, a piece of iron and cement mortar of stone cultural properties everywhere are forming precipitate of reddish brown and light gray being oxidized. About these stone cultural properties, most stone cultural propertieses show SD(severe damage) to MD(moderate damage) as result that record Deterioration degree. X-ray diffraction analysis result samples of each rock are consisted of mineral of quartz, orthoclase,plagioclase, calcite, magnetite etc. Quartz and feldspar alterated extremely in a microscopic analysis, and biotite that show crystalline form of anhedral shows state that become chloritization that is secondary weathering mineral being weathered. Also, see that show iron precipitate of reddish brown to crack zone of tuff everywhere preview rock that weathering is gone deep. Tuffs that accomplish stone cultural properties of study area is illustrated to field of Subalkaline and Peraluminous, $SiO_2$(wt.%) extent of samples pyroclastic tuff 70.08-73.69, ash tuff extent of 70.26-78.42 show. In calculate Chemical Index of Alteration(CIA) and Weathering Potential Index(WPI) about major elements extent of CIA pyroclastic tuff 55.05-60.75, ash tuff 52.10-58.70, granite 49.49-51.06 granitic gneiss shows value of 53.25-67.14 and these have high value gneiss and tuffs. WPI previews that is see as thing which is illustrated being approximated in 0 lines and 0 lines low samples of tuffs and gneiss is receiving esaily weathering process as appear in CIA. As clay mineral of smectite, zeolite that is secondary weathering produce of rock as result that pick powdering of rock and clothing material of stone cultural properties observed by scanning electron micrographs (SEM). And roots of lichen and spore of hyphae that is weathering element are observed together. This rock deep organism being coating to add mechanical weathering process of stone cultural properties do, and is assumed that change the clay mineral is gone fairly in stone cultural properties with these. As the weathering of rocks is under a serious condition, the damage by the natural environment such as rain, wind, trees and the ground is accelerated. As a counter-measure, the first necessary thing is to build the ground environment about protecting water invasion by making the drainage and checking the surrounding environment. The second thing are building hardening and extirpation process that strengthens the rock, dealing biologically by reducing lichens, and sticking crevice part restoration using synthetic resin. Moreover, it is assumed to be desirable to build the protection facility that can block wind, sunlight, and rain which are the cause of the weathering, and that goes well with the surrounding environment.