• Title/Summary/Keyword: geological region

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Design Strategies for Regionality in Contemporary Landscape Architecture (현대 조경 설계에서 지역성 구현 전략)

  • Choi, Jung-Mean
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.6
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    • pp.98-106
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    • 2016
  • This paper has attempted to reexamine current international circumstance and the meaning of regionality and discover the practical design strategy in the process of observing the trend of contemporary landscape architecture from the perspective of regionality. Contemporary landscape architecture has started to discover possibility in the local value and create identity. This tendency can be classified as follows: First, regionality is re-examined as a medium which can integrate nature, culture and city. As a concept which contains time and spatial continuity, landscape is a matter of the identity of land and area. Second, regionality has been reinterpreted and recreated by designers. Landscape designers attempt to restore the past memories and traces instead of adding a new concept after erasing previous physical features. This design attitude has spatialized time continuity. Third, site is seen as a palimpsest, not tabula rasa in contemporary landscape architecture. It has been attempted to visually materialize the natural and ecological processes and spatial features. Fourth, site is approached in a tectonic approach instead of analytical approach. It is attempted to organize and restore the geological and archeological memories and ecological processes. Differentiation has emerged as a critical design strategy in contemporary landscape architecture. However, regionality is also formed through an interaction with continuity as well as through differentiation. In this sense, the following possibilities can be reviewed as practical design strategies to realize regionality: First, a terra-tectonic approach discovers and selects possibility in the site and expresses the site, creating practical possibility which strengthens regionality. If the memory and conditions of the site are different, the identity would different as well. Second, continuity of region itself is a gene pool with comparative advantage. As a rough sketch of design, it acts as a loose conformity on designers' experience and practice. Of course, this approach is not absolute with some limitations. It is necessary to explore practical strategies.

Petrology of the Syenites in Sancheong, Korea (경남 산청 지역의 섬장암에 관한 암석학적 연구)

  • Ok, Eun-Young;Kim, Jong-Sun;Lee, Sang-Won;Kang, Hee-Cheol
    • The Journal of the Petrological Society of Korea
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    • v.24 no.1
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    • pp.25-54
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    • 2015
  • Syenite is not a common rock, unlike granitic rocks formed the major component of the continental crust. The aim of this study is to decipher the occurrences and detailed descriptive characteristics of the syenite distributed in Sancheong area, and to investigate the petrogenesis of the syenitic magma based on geochemical study. The dominant minerals in syenite are alkali feldspar (usually orthoclase and rarely microcline), plagioclase, amphibole, biotite, and quartz. Syenites are found in a wide variety of colors. The anhedral hornblende and biotite filling the boundary of feldspar and quartz indicate that the hydrous minerals were crystallized lately, and that water was insufficient at the beginning of crystallization in magma. According to the analysis of mineral composition, amphibole in syenite is mostly ferro-edenite, and the pressure is calculated as 3.3~4.9 kb with 11.9~17.3 km of emplacement depth. Biotite and pyroxene are plotted in the region of annite and hedenbergite, respectively. Based on petrochemical studies of major elements, syenite belongs to alkaline series, metaluminous, and I-type. On the other hand, the variation patterns of trace and rare earth elements of syenite differ from the patterns of diorite and granite. In the geochemical characteristics, syenite is different from gabbro-diorite spatially adjacent to syenite, as well as granite. These results suggest that each rock has been generated from the different sources of magma. Additionally, based on the experimental data, the syenitic magma can be formed (1) by the partial melting at a high pressure and dry system, (2) when the initial crystallization minerals to be residue with migration of the residual melts separated from the ascending cotectic magma (3) when fluorine compositions to be plentiful in the protolith and/or at depth of the magma. Based on the petrographic characteristics of the syenite, Sancheong syenitic magma may have been formed by partial melting in a dry system.

Aeromagnetic Interpretation of the Southern and Western Offshore Korea (한국 서남근해에 대한 항공자력탐사 해석)

  • Baag Czango;Baag Chang-Eob
    • The Korean Journal of Petroleum Geology
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    • v.2 no.2 s.3
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    • pp.51-57
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    • 1994
  • Analysis of the aeromagnetic data aquired by US Navy in the year 1969 permits us to predict a new sedimentary basin, Heugsan Basin, south of the known Gunsan Basin in Block Ⅱ. The basin appears to consist of three sub-basins trending NNW-SSE. The results of our analysis provide not only an independent assessment of the Gunsan Basin, but also new important information on the tectonic origin and mechanism for the two basins as well as for the entire region. The basin forming tectonic style is interpreted as rhombochasm associated with double overstepped left-lateral wrench faults. From the magnetic evidence, a few NE-SW trending major onshore faults are extended to the study area. We also interpreted the nature of the faults to be left-lateral wrenches. This new gross structural style is consistent with the results of recent Yeongdong Basin analysis by Lee. The senses of fault movement are also supported by the paleomagnetic evidence that the Philippine Sea had experienced an 80-degree clockwise rotation since the Eocene. Based on a 2 $\frac{1}{2}$ model study the probable maximum thickness of the sediments in the Gunsan Basin is approximately 7500 meters. We believe that the new Heugsan Basin was left unidentified because a high velocity layer may be overlying the basin. Because the overall structural configuration of the Heugsan Basin appears to be favorable for hydrocarbon accumulation, a detailed airborne magnetic survey is recommended in the area in order to verify the magnetic expression of this thick basin. A detailed subsequent marine gravity survey is also recommended in order to delineate the sedimentary section and to acquire supplemental data to the magnetic method only if an overlying high velocity layer is confirmed. Otherwise a high energy source seismic survey may be more effective.

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High-Resolution Paleoproductivity Change in the Central Region of the Bering Sea Since the Last Glaciation (베링해 중부 지역의 마지막 빙하기 이후 고생산성의 고해상 변화)

  • Kim, Sung-Han;Khim, Boo-Keun;Shin, Hye-Sun;Uchida, Masao;Itaki, Takuya;Ohkushi, Kenichi
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.3
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    • pp.134-144
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    • 2009
  • Paleoproductivity changes in the central part of the Bering Sea since the last glacial period were reconstructed by analyzing opal and total organic carbon (TOC) content and their mass accumulation rate (MAR) in sediment core PC23A. Ages of the sediment were determined by both AMS $^{14}C$ dates using planktonic foraminifera and Last Appearance Datum of radiolaria (L. nipponica sakaii). The core-bottom age was calculated to reach back to 61,000 yr BP. and some of core-top was missing. Opal and TOC contents during the last glacial period varied in a range of 1-10% and 0.2-1.0%, and their average values are 5% and 0.7%, respectively. In contrast, during the last deglaciation, opal and TOC contents varied from 5 to 22% and from 0.8 to 1.2%, respectively, with increasing average values of 8% and 1.0%. Opal and TOC MAR were low ($1gcm^{-2}kyr^{-1}$, $0.2gcm^{-2}kyr^{-1}$) during the last glacial period, but they increased (>5 and >$1gcm^{-2}kyr^{-1}$) during the last deglaciation. High diatom productivity during the last deglaciation was most likely attributed to the elevated nutrient supply to the sea surface resulting from increased melt water input from the nearby land and enhanced Alaskan Stream injection from the south under the restricted sea-ice and warm condition during the rising sea level. On the contrary, low productivity during the last glacial period was mainly due to decreased Alaskan Stream injection during the low sea-level condition as well as to extensive development of sea ice under low-temperature seawater and cold environment.

Conservation Status, Construction Type and Stability Considerations for Fortress Wall in Hongjuupseong (Town Wall) of Hongseong, Korea (홍성 홍주읍성 성벽의 보존상태 및 축성유형과 안정성 고찰)

  • Park, Junhyoung;Lee, Chanhee
    • Korean Journal of Heritage: History & Science
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    • v.51 no.3
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    • pp.4-31
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    • 2018
  • It is difficult to ascertain exactly when the Hongjuupseong (Town Wall) was first constructed, due to it had undergone several times of repair and maintenance works since it was piled up newly in 1415, when the first year of the reign of King Munjong (the 5th King of the Joseon Dynasty). Parts of its walls were demolished during the Japanese occupation, leaving the wall as it is today. Hongseong region is also susceptible to historical earthquakes for geological reasons. There have been records of earthquakes, such as the ones in 1978 and 1979 having magnitudes of 5.0 and 4.0, respectively, which left part of the walls collapsed. Again, in 2010, heavy rainfall destroyed another part of the wall. The fortress walls of the Hongjuupseong comprise various rocks, types of facing, building methods, and filling materials, according to sections. Moreover, the remaining wall parts were reused in repair works, and characteristics of each period are reflected vertically in the wall. Therefore, based on the vertical distribution of the walls, the Hongjuupseong was divided into type I, type II, and type III, according to building types. The walls consist mainly of coarse-grained granites, but, clearly different types of rocks were used for varying types of walls. The bottom of the wall shows a mixed variety of rocks and natural and split stones, whereas the center is made up mostly of coarse-grained granites. For repairs, pink feldspar granites was used, but it was different from the rock variety utilized for Suguji and Joyangmun Gate. Deterioration types to the wall can be categorized into bulging, protrusion of stones, missing stones at the basement, separation of framework, fissure and fragmentation, basement instability, and structural deformation. Manually and light-wave measurements were used to check the amount and direction of behavior of the fortress walls. A manual measurement revealed the sections that were undergoing structural deformation. Compared with the result of the light-wave measurement, the two monitoring methods proved correlational. As a result, the two measuring methods can be used complementarily for the long-term conservation and management of the wall. Additionally, the measurement system must be maintained, managed, and improved for the stability of the Hongjuupseong. The measurement of Nammunji indicated continuing changes in behavior due to collapse and rainfall. It can be greatly presumed that accumulated changes over the long period reached the threshold due to concentrated rainfall and subsequent behavioral irregularities, leading to the walls' collapse. Based on the findings, suggestions of the six grades of management from 0 to 5 have been made, to manage the Hongjuupseong more effectively. The applied suggested grade system of 501.9 m (61.10%) was assessed to grade 1, 29.5 m (3.77%) to grade 2, 10.4 m (1.33%) to grade 3, 241.2 m (30.80%) and grade 4. The sections with grade 4 concentrated around the west of Honghwamun Gate and the east of the battlement, which must be monitored regularly in preparation for a potential emergency. The six-staged management grade system is cyclical, where after performing repair and maintenance works through a comprehensive stability review, the section returned to grade 0. It is necessary to monitor thoroughly and evaluate grades on a regular basis.