• Animal Systematics, Evolution and Diversity
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• 제16권1호
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• pp.39-53
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• 2000

1994년 7월부터 1999년 6월까지 대한해협의 당사 및 인근수역에서 본인과 연구팀에 의해 조간대와 잠수 및 SCUBA 잠수등으로 수행되었다. 채집된 재료는 8과 17속 30종으로 동정 분류 되었고, 이 중 한 종, 주머니가죽멍게(Molgula hozawai)은 한국미기록 종이었으며, 그 외 29종은 당사 및 인근 수역에서는 처음으로 밝혀지는 종들이다. 이 지역 해초류의 생물지리학적 분포를 보면 30종 모두가 우리나라 천해종이며 난수역 종이다. 이들 중 23종은 거제도에서 이미 보고된 종이고, 12종은 춘도에서 보고되었으며, 6종 일로툼멍게(Eudistoma illotum), 새공멍게(Symplegma connec-tans), 가로줄멍게(Boltenia transversaria), 우주멍게(Microcosmus multitentacluatus), 네모가죽멍게(Pyura squamata)와 주머니가죽빛멍게(Molgula hozawai)는 이들 3개 난수역 지역에서는 처음으로 보고된 종이다. 그리고 11종(37%)은 3개 지역에 공통으로 나타났고 12종(40%)은 당사와 거제도에 공통이며, 한종(3%), 두줄미더덕(Styela canopus)은 당사와 춘도에서 공통종으로 나타났다. 따라서 당사 및 인근 수역의 해초류는 거제도와 춘도의 해초류상과 아주 유사하며 이는 이들 지역이 거의 같은 위도(북위 34$^{\circ}$ 40'- 35$^{\circ}$ 22', 동위 128$^{\circ}$ 45' - 129$^{\circ}$ 27')에 위치하고 있어 북상하는 따뜻한 쿠로시오 난류의 영향을 받기 때문으로 사료된다.

• 자원환경지질
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• 제27권1호
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• pp.65-80
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• 1994

The Tertiary $Ch{\check{o}}ngja$ basin is located in the southeastern coastal area of the Korean Peninsula. It is a lozenge shaped fault-bounded basin with circa $5{\times}5km$ areal extent, isolated from other Tertiary basins by the Cretaceous Ulsan Formation in-between. The northwestern boundary of the basin is a domino/listric type normal fault trending $N30^{\circ}E$, whereas its southwestern boundary is a dextral strike-slip fault (trending $N20^{\circ}W$) with a lateral offset of more than 1 km. The basin is bounded by the East Sea on the eastern margin. Basin-fills consist of extrusive volcanic rock (Tangsa Andesites) of Early Miocene (16~22 Ma in radiometric age), unconsolidated fluviatile conglomerate (Kangdong Formation) and shallow brackish-water sandstone ($Sinhy{\check{o}}n$ Formation). The latter yields abundant Vicarya-Anadara molluscan fossils of early Middle Miocene age. The Tertiary strata become younger toward the northwestern boundary-fault of the basin, showing a zonal distribution pattern parallel to the fault: the younger sedimentary formations occupy a narrow zone of 2 km width along the northwestern boundary-fault, whereas the older Tangsa Andesites underlie them unconformably in the eastern and southeastern portions of the basin. The strata in the basin, including the Tangsa Andesites, are tilted (about $20^{\circ}$) toward the northwestern boundary-fault Sedimentary strata thicken toward the boundary-fault, forming a wedge shaped half-graben structure. A number of small-scale syndepositional normal growth faults and graben structures are observed in the sedimentary strata. These extensional structures have the same trend as the normal northwestern boundary-fault which we interpret as a pull-apart detachment fault. These characteristics imply persistent extension during the basin evolution, caused by a NW-SE directed tensional force. The $Ch{\check{o}}ngja$ basin is, thus, a kind of syndepositional tectonic basin evolved in a strike-slip (pull-apart) regime. The latter was caused by a dextral simple shear associated with the NNW-SSE opening of the East Sea. In view of the fact that the normal growth faults do not cut through the uppermost portion of the youngest $Sinhy{\check{o}}n$ Formation, it is inferred that the tensional force came to be inactive in the early Middle Miocene. This is coincident in timing with the termination of the East Sea opening (15 Ma).

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.107-112
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• 2005

Road is built continuously along with development of industry and cut slope is happened necessarily in road construction. Geoengineers are executing cut slope stability analysis considering various cut slope condition such as topography, geology, hydraulic condition and so on. The Tertiary Jungja Basin is located in the southeastern coastal area of the Korea Peninsula. Jungja Basin area is created by geotectonic movement of the plate after Early Miocene epoch. The northwestern and southwestern boundary of the basin is fault zone. The Basement rock is hornfels (Ulsan Formation). Basin-fills consist of extrusive volcanic rock(Tangsa Andesites), unconsolidated fluviatile conglomerate(Kangdong Formation) and shallow brackish-water sandstone(Sinhyun Formation). The characteristics of cut slopes in this area is different with cut slopes in the other site. Soil layers in this area is unconsolidated sediments and is not formed the weathering and erosion of the rock. So, the depth of soil layer is very thick. Faults of this area are northwest-southeast and northeast-southwest direction. Expandible clay mineral as smectite, chlorite et al. detected from fault gouge using XRD. Therefore, Jungja Basin area must consider the characteristics of the faults and soil layers thickness necessarily cut slopes stability analysis.