• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2007.03a
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• pp.372-392
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• 2007

• The Journal of Engineering Geology
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• v.17 no.1 s.50
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• pp.27-40
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• 2007

Stratigraphy has been renewedly set up and the evolution of tectonic events related to basin formation has been exam-ined on the basis of fault-slip data analysis in the Tertiary Eoil and Waeup basins of the southeastern part of Korea. First of all, field mapping was carried out in detail for Tertiary formations and then paleostress analysis were peformed with more than 400 fault slip data collected from 11 sites in the Tertiary formations and the Yucheon Group. It is judged that both the Eoil and Waeup basins filled up with Tertiary deposits might be simultaneously formed in separate locations. The Janggi Group in the Eoil basin is divided into following stratigraphic units in ascending order: Gampo Conglomerte, Hongdeok Basalt, Nodongri Conglomerate and Yeondang Basalt, and the Bomkori Group in the Waeup basin: Waeupri Tuff; Andongri Conglomerate, Yongdongri Tuff and Hoamri Volcanic Breccia. Paleostress analysis by using striated faults reveals five sequential tectonic events: (1) NW-SE transtension (event I), (2) NW-SE transpression (event IIl), (3) NE-SW pure extension (event III), (4) N-S transpression (event IV) and (5) E-W pure compression (event V). Therefore, five sequential tectonic movements are closely associated with the formation and evolution of the Tertiary basins in the study area: tectonic event I of NW-SE extension is related to formation of the Tertiary basins during the late Oligocene to the Early Miocene, tectonic events II, III and IV caused the termination of the Tertiary basin opening and the crustal uplift in the study area, and tectonic event V upheaved the east coast or Korean Peninsula with compressive stress due to intense subduction of the Pacific plate into Asian continent since the Early Pliocene.

• The Journal of Engineering Geology
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• v.33 no.3
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• pp.427-438
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• 2023

We carried out a geological survey to classify the types of mass movement in Danyang Geopark (where various rock types are distributed) and analyzed the mechanical and hydraulic characteristics of landslide materials using a series of laboratory tests. Debris flows occurred in areas of limestone/marble, shale, and porphyroblastic gneiss, and limestone/marble landslides were distinguished from the others through the presence of karren topography. Soil tests showed that soil derived from weathered gneiss, which has a higher proportion of coarse grains, has a higher friction angle, lower cohesion, and larger hydraulic conductivity than soils from areas of limestone/marble, and shale. Rock failure mass movements occurred in areas of phyllite, sandstone, and conglomerate and were subdivided into plane failure, block-fall, and boulder-fall types in areas of phyllite, sandstone, and conglomerate, respectively. The shear strength of phyllite is much lower than that of the other types of rock, which have similar rock quality. The slake durability index of the conglomerate is similar to that of the other rock types, which have similar degrees of weathering, but differential weathering of the matrix and clasts was clearly observed when comparing the samples before and after the test. This study can help establish appropriate reinforcement and disaster prevention measures, which depend on the type of mass movement expected given the geological characteristics of an area.

• Proceedings of the KSEG Conference
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• 2005.04a
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• pp.235-242
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• 2005

본 연구에서는 퇴적암의 시험 관련자료 2,000 여건을 사암(역암 포함), 셰일 및 석회암으로 구분하여 흡수율, 단위중량, 일축압축강도, 점착력, 내부마찰각, 인장강도, 탄성계수, P파속도 및 S파속도 등의 특성치 분포도와 상관성을 분석하였다. 이러한 암석 특성치는 지하공간개발시 안전하고 경제적인 설계와 시공에 참고자료로 활용될 수 있는데 퇴적암의 강도특성 분석결과 사암과 석회암이 셰일 보다 전반적으로 양호하여 대규모 지하공간개발에 유리한 것으로 평가하였으며, 또 84% 신뢰도를 만족하는 범위에서 퇴적암의 암종별 공학적 특성치의 상관관계식을 유도하였다.

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.311-314
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• 2003

청양금산광상(군량맥)의 주변지질은 선캠브리아기의 변성퇴적암류, 중생대의 대동누층군 퇴적암류 및 소규모의 화성암과 맥암류가 분포된다. 선캠브리아기의 변성퇴적암류는 호상편마암, 각섬암질 편암, 사문암, 화강편마암, 미그마타이트질 편마암, 결정질석회암 및 석회규산염암으로 구성된다. 쥬라기 대동누층군 퇴적암류인 조계리층, 백운사층 및 성주리층은 광산의 동쪽에 북북동방향으로 분포되며 함장석각력사암, 사암, 역암, 셰일 및 이암으로 구성된다. (중략)

• The Journal of Engineering Geology
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• v.16 no.3 s.49
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• pp.227-233
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• 2006

Bedrock is inhomogeneous for its genetically diverse origins and geological conditions when it forms, and especially, conglomerates and core-stones are one of these typical composite geo-materials composed of weak matrixes and strong pebbles. Mechanical properties of these composite bedrocks, like a conglomerate, generally vary depending on the mechanical properties and distributions of pebbles and the matrix. Therefore, regarding the consequence of understanding mechanical property of bedrocks in the designing slopes, tunnels, and other engineering facilities, empirical rock classification methods generally applied in the mechanical property modeling may not be suitable and rather, we may need some other classification methods, or tests more specific for these inhomogeneous composite bedrocks. This study includes a series of analyses to see elastic behaviors and modulus of composite geo-materials using homogenization theory. Forty nine case models were made for the elastic analysis with considering 5 factors such as gravel content, gravel size, strength of matrix, sorting and dip angle. The results analyzed are applicable to calculate elastic modulus of composite geo-materials as conglomerates and core-stones.

• Economic and Environmental Geology
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• v.57 no.2
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• pp.205-217
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• 2024

This study evaluated the physical characteristics and quality of volcanic rocks distributed in the Jeju Island-Ulleung Island area as aggregate resources. The main rocks in the Jeju Island area include conglomerate, volcanic rock, and volcanic rock. Conglomerate is composed of yellow-red or gray heterogeneous sedimentary rock, conglomerate, and encapsulated conglomerate in a state between lavas. Volcanic rocks are classified according to their chemical composition into basalt, trachybasalt, basaltic trachytic andesite, trachytic andesite, and trachyte. By stratigraphy, from bottom to top, Seogwipo Formation, trachyte andesite, trachybasalt (I), basalt (I), trachybasalt (II), basalt (II), trachybasalt (III, IV), trachyte, trachybasalt (V, VI), basalt (III), and trachybasalt (VII, VIII). The bedrock of the Ulleung Island is composed of basalt, trachyte, trachytic basalt, and trachytic andesite, and some phonolite and tuffaceous clastic volcanic sedimentary rock. Aggregate quality evaluation factors of these rocks included soundness, resistance to abrasion, absorption rate, absolute dry density and alkali aggregate reactivity. Most volcanic rock quality results in the study area were found to satisfy aggregate quality standards, and differences in physical properties and quality were observed depending on the area. Resistance to abrasion and absolute dry density have similar distribution ranges, but Ulleung Island showed better soundness and Jeju Island showed better absorption rate. Overall, Jeju Island showed better quality as aggregate. In addition, the alkaline aggregate reactivity test results showed that harmless aggregates existed in both area, but Ulleungdo volcanic rock was found to be more advantageous than Jeju Island volcanic rock. Aggregate quality testing is typically performed simply for each gravel, but even similar rocks can vary depending on their geological origin and mineral composition. Therefore, when evaluating and analyzing aggregate resources, it will be possible to use them more efficiently if the petrological-mineralological research is performed together.

• The Journal of Engineering Geology
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• v.3 no.1
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• pp.63-74
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• 1993

There is many differences in morphology according to the geology in the basin of the Mortagne. The upstream where the substratum is composed of mainly the sandstone and conglomerate has the mountainous relief and the steep slope, so it is covered with the forest in regard to land use. Also the dimate influenced by the topography brings much of the predpitation and causes low temperature. The monthly oufflow and the peak flow are different between the upstream and downstream by these factors. It seems to be the very common and ordinary phenomena but this study is aimed at presenting the possibility of the quantitative amrnation between the factors and the flow regime in the future.

• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.72-72
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• 2010

지구과학은 자연과학 중에서 야외 현장에서 자연 현상의 관찰과 조사를 기초로 하는 학문이다. 특히 지질학 분야는 야외 조사를 통해 학생 스스로 탐구하고 문제를 발견함으로써 자연에 대한 흥미와 관심을 갖게 하여 지질학적 현상을 이해하게 한다. 그러나, 충북 지역에서 개발된 야외지질학습장의 부재와 입시위주의 교육환경으로 인하여 교사들은 한정된 범위에서 야외 현장 학습을 계획 및 실시하고 있다. 본 연구에서는 교사들에게 실제 야외학습의 패러다임을 사용한 야외학습장을 개발하여 지구과학 교육과정 중 야외학습의 교육적 자료로 제공 될 수 있도록 하였으며, 이러한 학습장을 토대로 지구과학교육에 야외학습을 쉽게 응용 할 수 있도록 하는데 그 목적이 있다. 이를 위하여 다양한 암석과 지질구조를 가지고 있고, 지리적으로 접근이 편리한 단양군 일대를 야외학습장으로 선정 하였다. 단양군 일대의 야외지질 학습코스에는 앨걸마운드, 어란석, 주상도 작성(석회암층군과 충식석회암), 두족류화석, 부정합관계에 놓인 역암층의 5개의 관찰지점이 있으며 실제 현장에서 각 관찰 지점별로 학생들이 활동할 수 있도록 야외지질 학습 자료를 제시하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.2
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• pp.99-105
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• 1986

This study was carried out to compare the soil profile development indices of Sinjeong series according to the distribution areas in Yeongnam district. The results obtained were as follows; 1. The soils studied were belong to fine loamy family of hilly residual soils derived from conglomerate. These soils were well drained and dominantly had 30-60% slopes, and used for forest. 2. The surfaces were typified by brownish red (5YR) or brownish yellow (10YR) loam, subsoils were clay loam of reddish brown (5YR) or reddish yellow (7.5YR) and the substrata were in dark reddish brown (5YR) or pink (7.5YR) sandy loam. 3. The indices of horizon development of the soils studied were from 0.18 to 0.38 and the index in illuvial horizons with clay films were over 0.36, that were higher than the others. The profile development indices were similar to each other ranging from 30.18 to 35.93. 4. Positive correlations were observed among horizon development indices and normalized values of structure, texture and consistences, but the relationship between profile development indices and consistences were not the same. 5. The amount of clay minerals formed in the soil horizons per 100g of parent materials were 1.1-1.6g and the rates of the clay leached were around 4.4-5.9%. 6. The sphericity and roundness of the gravels contained in the soils studied were 0.741 and 0.715, respectively. These similarity of "well rounded" gravels certify that the parent rocks were formed under similar environments.