• Title/Summary/Keyword: Ganghwa

Search Result 255, Processing Time 0.038 seconds

Petrology and petrochemistry of the so called "Ganghwa syenitic rock" in southeastern part of Ganghwa Island (강화도(江華島) 동남부(東南部)에 분포(分布)하는 소위(所謂) 강화섬장암질암(江華閃長岩質岩)에 대(對)하여)

  • Kim, Yong-Jun;OH, Mihn-Soo
    • Economic and Environmental Geology
    • /
    • v.11 no.2
    • /
    • pp.47-57
    • /
    • 1978
  • The study focused on the petrology and petrochemistry of the so called "Ganghwa syenitic rocks" which intruded into metasediment of basement in southeastern part of Ganghwa Island. The geologic sequence of the mapped area was shown in table 1, 10 model analyses and 7 chemical analyses on the rock samples taken from the Ganghwa syenitic rocks and Manisan granite have been used to discuss the nomenclature of the rocks and petrological relationship between rock types. The petrograpical and petrochemical features based on, the analyses are as follows: 1) Ganghwa syenitic rocks consist of Ganghwa alkali syenite and Ganghwa diorite porphyry which based on the classification of the subcommision on systematics of igneous of IGUS. Ganghwa diorite porphyry which occured as dike forms are intruded into Ganghwa alkali syenite. The rock forming minerals of Ganghwa alkali syenite are composed of perthite, plagioclase, quartz, hornblend and chlorite in major, and zircon, apatite, sericite and magnetite in minor. Ganghwa diorite porphyries consist of plagioclase, biotite, hornblend, orthoclase and chlorite, with, porphyritic texture. 2) In silica-oxides variation (Fig. 2) and AMF diagram (Fig_ 3), the Ganghwa alkali syenite is similar to the trend of Daly's average basalt-andesite-dacite-rhyolite than Skaergaard which shows the trend of the fractional crystallization of magma, and equivalent to the alkali rock series by Peacock. 3) The general trend of data points shift to plagioclase, and are superimposed on the alkali rich terminal part of the granodiorite province of SW Finland in normative Q-Kf-Pl(Fig. 4) and Or-Ab-An diagram respectively. The above-mentioned evidences suggested that the Ganghwa syenitic rocks are the differential products resulted by assimilation of intermediated magma and metasedment rock under relatively rapid cooling condition.

  • PDF

Local Movement of Shorebirds for Roosting between Ganghwa and Yeongjong Island in the West Coast of Korea

  • Kim, Hwa-Chung;Yoo, Jeong-Chil
    • The Korean Journal of Ecology
    • /
    • v.27 no.2
    • /
    • pp.73-77
    • /
    • 2004
  • Movement of shorebirds for roosting was studied to find their response to insufficient roosting area on Ganghwa Island. It was taken from two kinds of aspects of population fluctuation and direct observation of movement from March to October in 2002. Based on the data from their weekly fluctuation and flight observation, shorebirds on Ganghwa Island moved to roosts located far away. Shorebirds feeding at southern Ganghwa Island moved to Yeongjong Island for roosting during the spring tide period. High tide count showed that the number of shorebirds on Yeongjong Island increased strikingly, while the number of birds on Ganghwa Island decreased. As the tide level increased, the number of shorebirds on Ganghwa Island decreased in the fall migrating season (r$_{s}$= -0.81, p<0.001), whereas that on Yeongjong Island was not correlated significantly. Direct observation showed that some of the birds on the upper tidal zone of Ganghwa Island moved directly to the northern mudflat of Yeongjong Island during the flowing tide or dropped by flat zone on Seondu-ri. Insufficient coastal wetlands on Ganghwa Island induced them to move away from the island for roosting place and to endure costly flight energy expenditure. The development of wetlands on the southern Yeongjong Island would make them have no place available to roosts. Therefore this study proposes that shorebird roosts on Ganghwa Island should be created to conserve their habitat.t.

The history of ginseng cultivation in Ganghwa area (강화 지역의 인삼 재배 역사)

  • Lee, Sungdong
    • Journal of Ginseng Culture
    • /
    • v.2
    • /
    • pp.9-16
    • /
    • 2020
  • Ginseng was first addressed ever in the medical record in HyangYakGooGupBang (鄕藥救急方), the oldest Korean medical book published in Kingdom of Goryeo (918-1392) when Ganghwa was the provisional capital city at the time. It is believed that ginsengs in Ganghwa were planted and cultivated from 1100s. Intensive ginseng production in Ganghwa began when Ganghwa became the special district of the Kaesong Ginseng Union (開城人蔘組合) in 1920s, this intensive production continued till the Korean War in 1950. After the Korean War ended in 1953, ginseng production was resumed. In 1967, Ganghwa Ginseng Association (江華蔘業組合) was founded. The total acreage of ginseng harvested was nearly 200 ha in 1967 and it increased to ha 900 in 1974. By mid-1970s, Ganghwa became the largest ginseng region in Korea by total production and acreage. Most of ginseng roots cultivated in Ganghwa are six years old. Ganghwa, which was already well-known for red ginseng productions, has become even more famous for ginseng production.

Estimation of Oxygen Consumption Rates by Using an Oxygen Microelectrode in Ganghwa Intertidal Flat (강화도 남부 갯벌퇴적물에서 산소 미세전극을 이용한 산소소모율 추정)

  • Kim, Dong-Seon
    • Ocean and Polar Research
    • /
    • v.28 no.2
    • /
    • pp.119-127
    • /
    • 2006
  • We measured oxygen microprofiles using an oxygen microelectrode in Ganghwa intertidal flat in April and September. Oxygen consumption rate was calculated by using three different methods based on the oxygen microprofiles. The method using the PROFILE software was thought to be the most reliable among the three methods. The oxygen consumption rates calculated at station D1 by using the PROFILE software were 10.5 and 6.27mmol $m^{-2}d^{-1}$ in April and September, respectively. At station D2, they were 10.9mmol $m^{-2}d^{-1}$ in April and 5.39 mmol $m^{-2}d^{-1}$ in September. There was little spatial variation, but large seasonal variation, with almost two times larger values in April than in September. The higher rate in April is ascribed to higher oxygen concentration in the seawater and higher organic carbon content in the surface sediments, which probably accelerate oxygen consumption for organic matter decomposition in the sediments. Aerobic remineralization rates estimated from the oxygen consumption rates ranged from 4.14 to 8.07 mmol C $m^{-2}d^{-1}$ in Ganghwa intertidal flat, which were much lower than the anaerobic remineralization rate.

A Basic Study on the Landscape Characteristics of Cultural Heritage Area at the Gapgot Fortification in Ganghwa island (갑곶돈 일대 문화재 지역의 경관특징에 관한 기초연구)

  • Hyun, Sang-Kyu
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.33 no.1
    • /
    • pp.88-96
    • /
    • 2015
  • This purpose of this study was to identify the landscape characteristics of cultural heritage area in Gapgot fortification by performing text analysis of related literature and antique maps. And accumulate modern photograph to investigate the landscape of modern. As a additionally analysis, was examined landscape of Gapgot fortification area using aerial photograph. The results were as follows. First, Gapgot fortification has the historical value as symbolic and practical gateway to Ganghwa island caused by geographical position. And historical culture resources were located in Gapgot fortification area such as through traffic, military facilities. Secondly, According to literature and antique maps, Gapgot fortification area was village and military facilities from Goryeo dynasty. The village and military facilities was expanded with Jinhae pavilion since construct Ganhwa castle. Thirdly, In modern Gapgot fortification area appear consecutive coastal landscape when entry Ganghwa bridge. But, inhibiting elements of landscape should be remedied.

Foramniferal Characteristics in the Ganghwa Tidal Flat (강화 남부 갯벌의 유공충 특성)

  • Woo, Han Jun;Lee, Yeon Gyu
    • Journal of Wetlands Research
    • /
    • v.8 no.3
    • /
    • pp.51-65
    • /
    • 2006
  • Surface sediments for sedimentary analyses were sampled at 199 stations in the study area in August 2003. The surface sediments consisted of six sedimentary facies. Generally, sandy mud sediments dominated in the southern tidal flat of Ganghwa Island and sand sediments dominated in channel and subtidal zones of the western part of Ganghwa Island. The area of sandy mud sediment extended to eastward tidal flat compared to sedimentary facies in August 1997. In 30 surface sediment samples from the Ganghwa tidal flat and subtidal zone, 61 species were recorded in total assemblages, including 34 species of living population. Ammonia beccarii and Elphidium etigoense in living population and Ammonia beccarii, Elphidium etigoense, Jadammina sp. and Textularia earlandi in total assemblage were widely distributed. Generally, relatively large numbers of species and high values of species diversity occurred in the area of western part of tidal flat. Cluster analysis of total assemblages discriminates four biofacies. Biofacies 1 indicated eastern part of the tidal flat and biofacies 4 indicated western part of the tidal flat. Biofacies 3 were transitional zone between biofacies 1 and 4.

  • PDF