• Journal of the Korean association of regional geographers
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• v.13 no.1
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• pp.32-42
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• 2007

In Sagye coast of Andeok-myeon, southwestern Jeju, shore platform of noncohesive Hamori Formation, marine terrace deposit of round gravels, coastal dune composed of shell sand and volcanic sand, and back lake are linked closely with each other. In this paper, the formation process of Sagye coastal geomorphic system analysed by using OSL dating method is as follows: Firstly, Hamori Formation is a horizontal stratum filed up of tuff reworked by submarine volcanic eruption during 3$\sim$7.6 ka BP. Hollow at the boundary between Hamori Formation' flat and Kwangheak Basalt's gentle slope become a back lake when block is appeared over the sea level by uplift. Secondly, while Hamori Formation was laid below sea level, gravels which had been broken and abraded at southwestern rocky coast composed of Kwangheak basalt or been transported through the small stream from adjacent hillslope were deposited in rapid flow environment. Thirdly, deposition of round gravels was ceased by earth uplift, and shore platform was constructed by abrasion process of energy of swash moving forward. As altitude of shore platform is equal to high tidal level of spring tide, compared it with present high tidal level of study area, earth is uplifted about 105m since shore platform was formed. Fourthly, much sandy sediments transported from offshore bottom covered shore platforms and marine terrace deposits. Lighter sediments among sandy sediments was blown to back, formed secondary sand dune since about 500 year.

• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.55-57
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• 2010

부산 서구 두도(Doodo Islet 頭島)공원과 인접 암남(岩南)공원일대는 후기 백악기 (약 8,000만년 전) 유천층군의 다대포층(多大浦層)이 분포되어 있으며 이 층의 쇄설성퇴적암으로부터 공룡알 공룡알둥지 조각류 공룡 배아(embryo)화석 육식공룡과 초식공룡의 싸움터 유적 초식공룡의 피부화석 직경 30mm의 알(공룡?)화석 공룡골화석 새화석 나자식물 둥치화석 양치식물 잎과 목편 인상화석 등 동식물 화석이 대량으로 쏟아져 나왔고(발견자 : 필자와 한석운 공동), 종유석 해식동굴 해식애 해안단구 파식대지 풍화혈 구조 Stacks과 Stumps 해안자갈과 모래 등 지형자연사 유적과 장군산 등 후기 백악기의 화산 자연산 유적이 즐비하여 이곳은 국가적 보물로 평가되고 있다. 아래에 이들 자연사 유산을 기록으로 남길까 한다.

• Journal of the Korean earth science society
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• v.44 no.6
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• pp.611-628
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• 2023

This study aimed to explore the geo-educational value of Deokmyeong-ri in Goseong-gun, Gyeongsangnamdo, through field research. The study area comprises well-exposed outcrops, which can be used as field sites during field trip for studying sedimentary structures (normal grading bedding, cross bedding, ripple, and desiccation crack), coastal depositional environments (coastal cliff, shore platform, and gravel beach), basic principles of relative dating (unconformity, fault, intrusion, and xenolith), and columnar joints. This study evaluated the field sites based on the achievement standards and textbooks used in the science curriculum. The field sites have a high educational value because they exhibit typicality, as mentioned in the textbook, and provide study materials for enrichment learning. Furthermore, Deokmyeong-ri Area has well-developed tourist and educational infrastructures; thus, it is a safe place for geological education.

• Journal of the Korean earth science society
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• v.41 no.6
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• pp.588-598
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• 2020

The seafloor geology of Ieodo, a submerged volcanic island, has been poorly understood, although this place has gained considerable attention for ocean and climate studies. The main purpose of the study is to understand and elucidate types, distribution patterns and provenance of the surficial sediments in and around the Ieodo area. For this purpose, 25 seafloor sediments were collected using a box-corer, these having been analyzed for grain sizes. XRD (X-ray Diffraction) analysis of fine-grained sediments was conducted for characterizing clay minerals. The peak of Ieodo exists in the northern region, while in the southern area, shore platforms occur. The extensive platform in the south results from severe erosion by strong waves. However, the northern peak still survived from differential weathering. Grain size analyses indicated that gravels and gravelly sands with skeletons and shells were distributed predominantly on the volcanic apron and shore platform. Muddy sediments were found along the Ieodo and the adjacent deeper seafloor. Based on the analysis of clay mineral composition, illites were the most abundant in fine muds, followed by chlorites and kaolinites. The ratio plots of clay minerals for the provenance discrimination suggested that the Ieodo muds were likely to be derived from the Yangtze River (Changjiang River). As a consequence, gravels and gravelly sands with bioclastics may be supplied from the Ieodo volcanic apron by erosion processes. Wave activities might play a major role in transportation and sedimentation. In contrast, fine muds were assumed to be derived from the inflow of the Yangtze River, particularly in summer. Deposition in the Ieodo area is, therefore, probably controlled by the inflow from the Changjiang Dilute Water and summer typhoons from the south.

• Journal of The Geomorphological Association of Korea
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• v.19 no.1
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• pp.99-108
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• 2012

To consider geomorphological and geological characteristics to Gatbawi(the 500th natural monument), it was investigated with the aspect of scale, form, mineralogy, chemistry and weathered state. Showing typically erosional features, micro-terrains as sea cliffs, sea notches, marine plateaus and tafoni developed well on coastal areas near the monument. Sea cliffs are vertical and form sea notches in their bases. Coastal terraces are 3.5m in width and 20m in trace. Tafoni are honey combed. The monument is mainly composed of quartz, plagioclase, microcline, biotite, sericite in mineral and corresponded to crystalline tuff dominated in quartz and plagioclase. It has 23.60~28.27 wt.% of $Al_2O_3$, 3.27~5.80 wt.% of $Na_2O$, and 0.11~0.20 wt.% of Cl in chemical contents, leveling higher than those of earth crust standards. It is considerably weathered on the basis of CAI(77.42~83.93%). The monument is very useful for natural perspective tourism and education. Therefore, it is necessary that several ideas as guide plates, observing telescope, explaining guider, education programs connected with related services, touring goods, picture for books on utilization on the monument must establish.