• Title/Summary/Keyword: MT survey

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MT surveys near Century Zinc Mine, NW Queensland, Australia (호주 Century 아연 광산에서의 MT 탐사)

  • Lee, Tae-Jong;Lee, Seong-Kon;Song, Yoon-Ho;Cull, James
    • Geophysics and Geophysical Exploration
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    • v.10 no.4
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    • pp.345-352
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    • 2007
  • Two-dimensional (2D) MT surveys near the Century mine in Australia have been performed with very far remote reference in Esashi, Japan (RR_ESS) as well as Gregory Downs (RR_GREG), which are roughly 6,400 km and 80 km apart from the survey area, respectively. Good quality of MT data could be obtained by remote reference processing with RR_GREG, while the coherency of magnetic fields between field sites and RR_ESS was not sufficient to be used as remote data. Both 2D and 3D inversion of 2D profile data represented the general geological structure beneath the survey area. The main target of the survey, Termite Range Fault, appeared as a boundary between a conductive block to the north and a resistive block to the south in the reconstructed resistivity section, and is inclined slightly to the north-east direction.

Analysis of Benthic Macroinvertebrate Community and Biological Evaluation of Water Quality in the Gapyung Region of the Upper North Han River, Korea (한강 상류수계(가평)의 저서성 대형무척추동물 군집분석 및 생물학적 수질평가)

  • 배경석;유승성;원두희;김민영;신재영
    • Journal of Environmental Health Sciences
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    • v.28 no.2
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    • pp.149-160
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    • 2002
  • Analysis of benthic macroinvertebrate community structure and biological estimation of water quality by the benthic macroinvertebrates from the Mt. Myungji(1267m), Mt. Kalbong(840m), Mt. Daegeum(704m) and Mt. Jubal(489m) region of Gapyung-gun, Kyunggi-do were investigated from April to November, 2001. Total taxa of benthic macroinvertebrates were 105 species, 38 families, 13 orders, 5 classes in 4 phyla. Aquatic insects were 33 species in ephemeroptera, 5 species in odonata, 13 species in plecoptera, 2 species in hemiptera, 1 species in megaloptera, 27 species in trichoptera, 3 species in coleoptera and 13 species in diptera, respectively. Non-insects were 1 species in platyhelminthes, 5 species in gastropoda, 1 species in oligochaeta, 1 species in crustacea, respectively. Ephemeroptera, trichoptera and plecoptera as indicators in clean water were very abundantly. Occurrence species at each survey area was 67 species at Mt. Myungji and 69 species at Mt. Kalbong, 48 species at Mt. Daege.um and 47 species at Mt. Jubal, respectively. Mean species diversity indices at Mt. Myungji, Mt. Kalbong, Mt. Daegeum and Mt. Jubal were 3.30, 3.33, 2.59 and 3.43, respectively. According to the saprobic system based on the species diversity indices of benthic macroinvertebrates, Mt. Myungji, Mt. Kalbong and Mt. Jubal are determined as Limnosaprobic area, respectively, but Mt. Daegeum is determined as $\beta$-mesosaprobic area.

The Value and Application of The Mt. Palgong in Daegu (대구 팔공산의 가치와 활용방안)

  • JEON, Young-Gweon
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.2
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    • pp.51-68
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    • 2012
  • This paper aims to investigate the value in culture, history and ecology of the Mt. Palgong. It attempts to build the strategy for making use of The Mt. Palgong by literature survey, interview, and field survey. The main results are as follows: 1) The boundary of physical geography of the Mt. Palgong is classified into two. The boundary of the Mt. Palgong limits to granite mass block in a narrow sense, while in a broad sense, the boundary of the Mt. Palgong includes a contact aureole to be bordered on the Mt. Palgong granite mass block. The boundary from a cultural viewpoint limits to Daegu city(excluding Dalseong county) and Gyeongsan city, Yeongcheon city, Gunwi county and Chilgok (Dongmyeong-myeon, Giseong-myeon) in Gyeongbuk province. 2) In the geological boundary, one of the south-west slope is clearer than that of the north-east slope of the Mt. Palgong. The landforms such as tor, sheeting joint and gutter are well developed as a whole. Mountain landform such as boulder stream, polygonal cracking is relatively well developed on the south-west slope, while river landform is relatively well developed on the north-east slope of the Mt. Palgong. 3) It is necessary to develope various masterpiece of interesting stories related to Mt. Palgong in order to make the Mt. Palgong excellent tour complex. 4) It is desirable to designate the Mt. Palgong as a national park for systematic management. A master plan should be ultimately designed to raise brand value of Daegu city, and make good identity of the city by restoring 'The Mt. Palgong Jecheondan' and registering 'Gatbawi' as world heritage. 5) It is reasonable that the method of development in The Mt. Palgong should be based on the pattern of 'slow life town'. 'The Mt. Palgong museum' will then be designed to give visitors all the informations on The Mt. Palgong.

Study of geological structure in area of Hwasan caldera using geophysical method (지구물리학적 방법에 의한 화산 칼데라 지역의 지질구조 연구)

  • Kwon, Byung-Doo;Lee, Heui-Soon;Yang, Joon-Mo;Park, Gye-Soon;Eom, Joo-Young;Kim, Dong-Oh
    • 한국지구물리탐사학회:학술대회논문집
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    • 2007.06a
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    • pp.267-272
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    • 2007
  • Uiseong subbasin belonging to Kyungsang basin resulted from volcanic activity in the late Cretaceous. In this study, we carry out MT and gravity survey at the Hwasan caldera, which was formed of volcanic and abyssal rocks complex, then analyze and identify geological substructure. Potential survey such as gravity and magnetic survey has been mainly carried out in former studies, so depth information for understanding substructure was not enough. To complement a potential survey, we use MT method, which has high vertical resolution. Moreover we make a simple 2D model comparing with former study. The result of MT and gravity 2D modeling shows that this area is roughly composed of 3 layers; The bottom layer is a basement. In the second layer, intrusive rocks having high resistivity is placed along the ring faults and the sedimentary layer of low resistivity is inside caldera. The highest layer is alluvium. To comprehend the 3D structure of the Hwasan caldera, we perform 3D gravity inversion, and construct the 3D model from the result of 3D gravity inversion. MT responses are calculated by using the constructed 3D model and the 3D model of the Hwasan caldera's structure is suggested after comparing the calculated values with the observed values at MT line.

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Estimating Economic Value of Environmental Resource - Focussed on the Preservation Value of Bong-seo Mt. by Using the CVM in Cheonan City (환경자윈의 경제적 가치평가에 관한 연구 - 천안시 봉서산의 보존가치 추정을 중심으로 -)

  • 이지은;허승욱
    • Korean Journal of Organic Agriculture
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    • v.11 no.1
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    • pp.39-53
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    • 2003
  • This study attempted to estimating economic value of environmental resource by using the contingent valuation method(CVM), known as one of the tool measuring the economic benefits. To analysis the preservation value of Bong-seo Mt.. the surveys were conducted for citizens resident in Cheonan city. The sample sizes of the survey were 200 respectively. The survey method adopted face-to-face interview method as a mean of correcting useful response. This study considers models for evaluating the willingness to pay(WTP) based on payment card contingent valuation survey data and has attempted to measure goodness of fit for the data obtained from the survey design. It was estimated that the average WTP of Cheonan citizens for a maintenance and management of Bong-seo Mt. was 5,010 won per month and 60 ,118 won per year. When it is translated by total number of households in Cheonan city, there is the preservation value of approximately 8.8 billion won per year. On the other hand, total expense of development increased about 1.7 times over including application of the preservation value.

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Mammalian Status of Mt. Cheomchalsan in Jindo, Korea

  • Shin, Hwa-Yong;Lee, Hwa-Jin;Kim, Woo-Yeol;Yoon, Hee-Nam;Lee, Jung-Hyo;Ha, Jeong-Wook
    • Animal Systematics, Evolution and Diversity
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    • no.spc9
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    • pp.80-83
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    • 2016
  • In order to analyze a status of animal in an area where has been became a land cause of Jindo Grand Bridge established on Jindo island area, mammal status in the biggest mountain in Jindo province, Mt. Cheomchalsan has been investigated for four times from May to October of 2016. According to the investigation, 5 orders, 9 families and 15 species of inhabitation was confirmed, and water deer (Hydropotes inermis), raccoon (Nyctereutes procyonoides), cat (Felis catus), and etcetera were dominant. Biodiversity and evenness index were likely to be high as 2.24 and 0.83, respectively and it is considered that favorable condition of natural ecosystem for inhabitation of mammalian is established. Meanwhile, since the cat designated as control species is confirmed as a dominant species, it is supposed that continuous management is necessary.

The Structure Analysis of Plant Communities of Betula ermanii Community in Subalpine (아고산대 사스래나무군락의 식물군집구조 분석 연구)

  • Da-Um Yun;Choong-Hyeon Oh
    • Korean Journal of Environment and Ecology
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    • v.38 no.3
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    • pp.338-350
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    • 2024
  • A vegetation survey was conducted and analyzed on 25 survey plots of Betula ermanii communities in the subalpine zone of Mt. Gariwang, Mt. Balwang, Mt. Bangtae, and Mt. Hambaek in Gangwon-do. As a result of TWINSPAN and DCA analysis, the community was divided into a total of 3 communities: Betula ermanii-Quercus mongolica community(GroupI), Betula ermanii-Acer pseudosieboldianum community (GroupII), and Betula ermanii community(GroupIII). As a result of the vegetation structure analysis, Betula ermanii-Quercus mongolica community(GroupI) is located on the periphery of the Mt. Bangtae trail at altitude of 1,082~1,192m, and Betula ermanii-Acer pseudosieboldianum community(GroupII) is located on the ridges and slopes of Mt. Bangtae, Mt. Gariwang, and Mt. Hambaek at altitudes of 1,230~1,373m. Betula ermanii-Quercus mongolica community(GroupI) and Betula ermanii-Acer pseudosieboldianum community(GroupII) are currently dominated by Betula ermanii, but after long term, it is expected that they will transe to Quercus mongolica. The Betula ermanii community(GroupIII) is located the summit of Mt. Hambaek and the summit of Mt. Balwang at altitude of 1,428~1,464m. It is expected that the community will be maintained as Betula ermanii community, because Betula ermanii is very dominant, and so the next generation dominant species is maintained by Betula ermanii. Betula ermanii community generally appear above 1,000 m above sea level, and the higher the altitude, the more dominant the Betula ermanii are. As a result of the soil analysis, the soil characteristics shows a similar pattern to the subalpine belt of Daecheongbong Peak of Mt. Seoraksan and Banyabong Peak of Mt. Jirisan. As a result of the species diversity index analysis, the species diversity index was 1.210~1.293, the abundance index was 0.698~0.795, and the dominance index was 0.208~0.302.

Magnetotelluric survey applied to geothermal exploration: An example at Seokmo Island, Korea (자기지전류법을 이용한 석모도에서의 지열자원 탐사)

  • Lee, Tae-Jong;Han, Nu-Ree;Song, Yoon-Ho
    • Geophysics and Geophysical Exploration
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    • v.13 no.1
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    • pp.61-68
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    • 2010
  • A magnetotelluric (MT) survey has been performed to delineate deeply extended fracture systems at the geothermal field in Seokmo Island, Korea. To assist interpretation of the MT data, geological surveying and well logging of existing wells were also performed. The surface geology of the island shows Cretaceous and Jurassic granite in the north and Precambrian schist in the south. The geothermal regime has been found along the boundary between the schist and Cretaceous granite. Because of the deep circulation along the fracture system, geothermal gradient of the target area exceeds $45^{\circ}C/km$, which is much higher than the average geothermal gradient in Korea. 2D and 3D inversions of MT data clearly showed a very conductive anomaly, which is interpreted as a fracture system bearing saline water that extends at least down to 1.5 km depth and is inclined eastwards. After drilling down to the depth of 1280 m, more than 4000 tons/day of geothermal water overflowed with temperature higher than $70^{\circ}C$. This water showed very similar chemical composition and temperature to those from another existing well, so that they can be considered to have the same origin; i.e. from the same fracture system. A new geothermal project for combined heat and power generation was launched in 2009 in Seokmo Island, based on the survey. Additional geophysical investigations including MT surveys to cover a wider area, seismic reflection surveys, borehole surveys, and well logging of more than 20 existing boreholes will be conducted.

Vascular Plants Distributed in the Naknam-Jeongmaek - Focused on Gilmajae, Mt. Muryang, Mt. Yeohang, Mt. Muhak, Mt. Cheonju and Mt. Sineo - (낙남정맥에 분포하는 관속식물상 - 길마재, 무량산, 여항산, 무학산, 천주산, 신어산을 중심으로 -)

  • Oh, Hyun-Kyung;Kim, Dong-Pil;You, Ju-Han
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.19 no.2
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    • pp.19-39
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    • 2016
  • This study was carried out to investigated the flora of Naknam-Jeongmaek, Korea. The survey sites were Gilmajae, Mt. Muryang, Mt. Yeohang, Mt. Muhak, Mt. Cheonju and Mt. Sineo. The flora were summarized, numbering 666 taxa including 112 families, 357 genera, 574 species, 4 subspecies, 73 varieties and 15 forms. The threatened species was Aconitum austrokoreense. The rare plants were 12 taxa including Asarum maculatum, Wikstroemia ganpi, Viola albida, Tricyrtis macropoda and so forth. The Korean endemic plants were 19 taxa including Salix koriyanagi, Thalictrum actaefolium var. brevistylum, Weigela subsessilis, Hosta minor and so forth. The specific plants by floristic region were 81 taxa including 38 taxa of grade I, 19 taxa of grade II, 16 taxa of grade III, 7 taxa of grade IV and 1 taxa of grade V. The naturalized plants were 32 taxa including Rumex crispus, Physalis angulata, Erechtites hieracifolia, Taraxacum officinale and so forth. The invasive alien plants were Ambrosia artemisiifolia and Aster pilosus.

DC Resistivity Survey Design for Deep Magma in Mt. Baekdu Using Distributed Acquisition System (백두산 심부 마그마 탐사를 위한 분산계측 시스템을 이용한 전기비저항탐사 설계)

  • Lee, Hyosun;Jung, Hyun-Key;Cho, Sung-Ho;Kim, Yesol;Lee, Youn Soo;Min, Dong-Joo
    • Journal of the Korean earth science society
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    • v.40 no.2
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    • pp.177-187
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    • 2019
  • Several volcanic activities have continued in Mt. Baekdu since the Millennium eruption, and these phenomena have increased the need for volcanic activity surveillance. Various geophysical approaches are needed to obtain the depth and size of magma chamber that lie several kilometers below the surface. We examined the applicability of direct-current resistivity survey in this study. In order to explore the deep magma chamber of Mt. Baekdu, which has a spatial limitation due to the borderline, a large-scale survey with a length of tens of kilometers should be conducted. This type of survey requires a distributed measurement system and optimized exploration designs. Therefore, we propose survey designs taking advantage of our developed distributed acquisition system and analyze the applicability using numerical simulation. We confirmed that our designs that use single survey line with offline transmitting points show comparable results to the conventional 3D survey. It is expected that our research result can contribute to the deep geophysical exploration in Mt. Baekdu.