• Economic and Environmental Geology
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• v.37 no.5
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• pp.543-554
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• 2004

Analysis of multi-channel seismic reflection and well data serves to detail the structural evolution of the northern Okinawa Trough, southern offshore Korea. The overall structural style of the area is characterized by a series of half grabens and tilted fault blocks bounded by basement-involved listric normal faults. Most half grabens and tilted fault blocks developed in the direction of NNE-SSW, parallel to the axis of the Okinawa Trough. Orientation and distribution of the listric faults also suggest the development of transfer faults in NW-SE direction. The rifting phase of the northern Okinawa Trough have been established on the basis of structural and stratigraphic analyses of depositional sequences and their seismic expressions. Major phase of rifting probably started in the Late Miocene and the most active rifting occurred during the Early Pliocene. The rifting produced a series of half grabens and tilted fault blocks bounded by listric normal faults. It appears that the rifting activity has become weaker since the Late Pliocene, but the Pleistocene sediments faulted by listric faults bounding tilted fault blocks suggest that the rifting activity is probably still in progress.

• Journal of the Korean Geophysical Society
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• v.7 no.3
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• pp.225-232
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• 2004

To investigate the depositional environment and the geological structure of the Jeju Basin in the South Sea of Korea, we acquired 54-channel seismic data of about 1,980 line-km. The study area lies at the northeastern part of the East China Sea Trough, a Tertiary back-arc basin. The sedimentary basin formed by rifted activities resulted in the formation of graben and/or half-graben structures. The basin is composed of pre-rift, syn-rift and post-rift sediments bounded by regional unconformity. The pre-rift and syn-rift sediments consist of Oligocene, Early and Middle Miocene sequence, whereas the post-rift sediments consist of Late Miocene and Plio-Pleistocene sequences. Seismic and well data from the Jeju Basin indicate that Oligocene-Miocene sediments were deposited under fluvial and lacustrine depositional conditions. Following compressional tectonic movements in the Late Miocene time and a subsequent period of erosion, regional subsidence during the Pliocene time brought the Jeju Basin under marine conditions, resulting in the deposition of dominantly marine sediments.

• Proceedings of the KSEEG Conference
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• 2005.04a
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• pp.317-319
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• 2005

• Economic and Environmental Geology
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• v.36 no.6
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• pp.491-499
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• 2003

The Okinawa Trough is a rift basin formed by extension. Analysis of multichannel seismic reflection profiles from the northwestern margin of the northern Okinawa Trough reveal that the trough is characterized by a series of tilted fault blocks bounded by listric normal faults and half-grabens developed between blocks, showing typical rifted structures. The trough display three kinds of sedimentary sequences with different seismic reflection characteristics: prerift, synrift and postrift sediments. The prerift sequence develops parallel to the dip direction of tilted fault blocks. The synrift sediments, mostly deposited in the half-grabens between tilted fault blocks, are generally well characterized by divergence of the reflectors towards the blocks indicating contemporaneous deposition during tilting. The postrift sediments are featured by continuous and parallel reflectors. The width of the half-graben and the throw-displacement rate of the basin bounding fault are closely connected. The throw-displacement rate is the maximum when the rifting event is the most active and the width of the half-graben is proportional to the rate.

• Journal of the Korean Geophysical Society
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• v.9 no.4
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• pp.409-416
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• 2006

Reflection seismic survey has been conducted using R/V Yuzmogeologia of Russia on the area of between northern part of Powell basin and South Scotia Ridge. 48-channel seismic data have been processed using Promax system. Hesperides and Eastern Deep located in the central part of the South Scotia Ridge show similar geological structure comprising two distinct sedimentary layers. The lower layer filled with fault breccia is considered to be formed with the expansion of the deeps. The upper layer is filled with pelagic sediments which implies this layer is formed after the spreading of the deeps has stopped. The south branch of the South Scotia Ridge is characterized by bigger width than the north branch. Topographical depression shown in the south branch is formed by many faults accompanied with the seafloor expansion of Powell basin.

• The Korean Journal of Petroleum Geology
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• v.9 no.1_2 s.10
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• pp.16-23
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• 2001

The study area in the East Sea is located on the northeastern margins of the Ulleung Basin near the Kita-Yamato Bank. The research area provides the important clue to the development of Miocene basins which are characterized by the normal faults and volcanic activities related to rifting in the continental crust. Kita-Yamato Bank is a small sediment-filled graben which was formed by failed rifting in the Early Miocene. The basins rapidly vary the bathymetry, depth of acoustic basement and thickness of sedimentary layer. The tension in the study area caused the extensional lithospheric deformation before/during the Early Miocene. In consequence, tectonic forces resulted in the depression or subsidence of basement from continental rifting in the Kita-Yamato Bank followed by the opening of the Ulleung Basin, and caused the onset of graben or half-graben structure bounded by large blocked syn-rift faults. Afterward no significant tectonic deformation exists, with the consequence that post-rift normal faults with small heave were formed and reactivated by the resultant forces such as tectonic subsidence, sediment loading and volcanic activity. The Cenozoic sediment layer has a maximum thickness of 1.0 s along the center of the graben or half-graben, which overlies the consolidated acoustic basement. Seismic units V and IV supposed to be syn-rift sedimentary rocks are deformed by both the volcanic activities and numerous basement-involved normal faults induced from extension. In the uppermost layer, slump scars resulted from the slope failure are recognized.

• The Korean Journal of Petroleum Geology
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• v.14 no.1
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• pp.53-62
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• 2008

Seismic interpretation was carried out based on biostratigraphy of Fukue-1 well in Japan side of the Domi Basin and compared with the Cheju Basin and Tertiary basins in north-west Kyushu. East China Sea Basin including Domi Basin began to develope in the latest Cretaceous$\sim$Paleocene related to rifting. The basin was filled with a thick package of syn-rift sediments during Paleocene to Oligocene and was under post-rift stage effected by transtenssion during Miocene. Previous studies suggest that the basin had been mostly filled with Miocene formation (>3 km), but the Miocene formation is interpreted to be comparatively thin in this study. The thickness of the Miocene formation varies from tens of meters to hundreds of meters and become thicker to the south-west of Cheju Basin. The index taxa of the Oligocene$\sim$Eocene nannofossils and dinoflagellates found in the Cheju Basin and Tertiary basins in north-west Kyushu also corroborate the result of this study.

• Journal of the Mineralogical Society of Korea
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• v.25 no.1
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• pp.51-61
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• 2012

터키는 알파인 조산대 내의 테티얀 광상대(Tethyan belt)에 위치한다. 이 광상대는 섭입과, 충돌, 열개 운동으로 형성되었고 후기 백악기에서 신생대 화성암류와 오피올라이트(ophiolite)와 관련된다. 터키 지표의 5.5%를 덮고 있는 변성지괴는 북동부의 스트란야(Strandja), 카쟉(Kazdag), 서부의 멘데레스(Menderes), 중부의 키르세히르(Kirsehir), 남동부의 비틀리스(Bitlis)와 포투르지(Poturge)에 분포한다(그림 3과 4). 비교적 연구가 많이 진행된 서부지역의 변성지괴 연구결과에 따르면 변성작용연대는 선캠브리아기에서 올리고세이다. 변성상은 녹색편암상과 각섬암상에서 에콜로자이트상과 백립암상에 이른다(Yigit, 2009). 상기 여러 지괴는 여러 번에 걸쳐 변성작용을 겪었다. 서부의 멘데레스 지괴는 다섯 개의 변성상을 보여주고 있으며, 두 번째 변성작용까지는 알파인 조산운동 이전의 시기이다. 다양한 지질과 지체구조는 터키의 다양한 광상의 부존 가능성을 가능케 한다. 주요자원인 금-동-몰리브덴 광상은 주로 후기 백악기에서 신생대의 화산호와 관련된 반암동과 천열수 광상이다. 동-연-아연 광상은 VMS 중 쿠로코와 사이프러스형 광상과 MVT 광상에 속한다. 알려진 크롬광상의 대부분은 포디폼광상이며 알파인-오피올라이트 암석과 관련된다.

• The Korean Journal of Petroleum Geology
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• v.7 no.1_2 s.8
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• pp.7-12
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• 1999

A new high-resolution rnagnetotelluric (MT) survey was conducted for pull-apart basin analysis (Cretaceous Eumsung Basin), combined with surface sedimentological results. Two cross-basinal MT profiles represent an asymmetric form with a subbasin in the southeastern part. These basinal architectures are well compatible with paleoflow directions and facies transitions of surface sedimentology. The results also suggest that the basin fills reflect pull-apart opening with rapid subsidence of the central blocks. Combined with the surface sedimentological data on asymmetric lithofacies distribution, facies transitions, and paleoflow directions of the alluvio-lacustrine systems, the MT data help explain basin-fill processes during the basin formation. For petroleum exploration and basin analysis, the high-frequency MT technique can be a useful substitute for the costly burden of a seismic-reflection survey on land.

• Journal of Chest Surgery
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• v.34 no.6
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• pp.485-489
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• 2001

Background: The most important factor in preventing sternal complications is stable sternal approximation. We have tried to find the most effective sternal closure method by examining the incidence of sternal dehiscence with or without infection in patients with cardiac surgery through median sternotomy. Material and Method: This study was performed in 489 patients over 45 years of age with median sternotomy for open cardiac surgery. Simple closure with interrupted 6 wires was performed in 159 patients, figure-of-8 closure technique in 119, overlapping interrupted closure using 10 wires in 150, and combined closure technique of interrupted simple closure and figure-of-8 suture closure in 61. Two hundred thirty-four patients underwent valve and aortic operations and 213 patients coronary artery bypass surgery. Result: Sternal dehiscence with or without infection occurred in 12 (2.5 %) patients. The complication developed in 5 of 159 patients (3.1%) with six interrupted simple closure, in 4 of 119 patients (3.4%) with figure-of-8 closure, and in 3 of 150 patients (2.0%) with overlapping interrupted closure using 10 wires, but there was no complication in 61 patients with combined closure technique (relative risk for other closure techniques, p<0.05). There was no significant difference in the incidence of the sternal complication between valve and aortic operation group and coronary artery bypass group (3.0% vs 2.3%, not significant), but diabetes mellitus was a significant independent risk factor (odds ratio and multivariate analysis, p<0.05). Conclusion: The sternal closure technique that combines simple interrupted suture closure and figure-of-8 suture closure may be a more useful technique to enhance sternal stabilization compared to other closure techniques, such as simple interrupted closure, 8-figure closure, and overlapping interrupted closure.