• Title/Summary/Keyword: Ground cave-in

Search Result 38, Processing Time 0.022 seconds

Fundamental Parameter 법에 의한 만장굴용암 쌍자석주의 형광X선분포

  • ;Ko, Mun-Ok;Kim, Gyung-Sik
    • Journal of the Speleological Society of Korea
    • /
    • v.19 no.20
    • /
    • pp.29-62
    • /
    • 1989
  • Cheju Island, which was formed by volcanic activity, is an oval in its shape with the major axis 80km and the minor axis of 40km. The island holds in its heart Mt. Hanala rising 1,950m above the sea. Petrological study of this volcanic island has been made actively by Sang-Man Lee, Chong-Kwang Won and Moon-Won Li. The chronological measurements of the island by Chong-Kwan Won and Moon-Won Lee showed that it is composed of Sanbangsan trachytes and Backlokdam trachytes(25,000 year ago). These reports are based on the chemical analysis and the rediometric chronological measurements on the ground. However, there has been no reports about the inside of caves. We made an (composition) analysis of the inside of Manjang Cave by the fundamental parameter method in X-ray fluorescence spectrometry. The fundamental parameter method in X-ray fluorescence spectrometry is nondestructive analysis. and it enables us to make the values processed by a computer. The results obtained by this methods are as follows: SiO$_2$(49%), $Al_2$O$_3$(17%), Fe$_2$O$_3$(13%), CaO(8.1%), MgO(5.5%), Na2O(3.6%), TiO$_2$(2.1%), $K_2$O(0.86%), P$_2$O$_{5}$(0.28%), and MnO(0.20%) respectively. The data obtained by the fundamental parameter method in X-ray fluorescene was compared with the data provided by Chong-Kwan Won and Moon-Won Lee. Our measurement was made by K-Ar-method in cooperation with T. ITAYA. The samples are of 30,000-420,000 years ago. The composition of the values of our underground analysis with the existing values obtained by the analyses on the ground produced new data about Cehju volcanic island.d.

  • PDF

Performance of Heat Pump System Using Underground Air as Heat Source (지하공기를 이용하는 농업시설용 난방시스템)

  • Kang, Youn-Ku;Ryou, Young-Sun;Kim, Young-Hwa;Sung, Moon-Seok;Kim, Jong-Koo;Jang, Jae-Kyoung;Lee, Hyoung-Mo
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2009.11a
    • /
    • pp.587-589
    • /
    • 2009
  • The districts of underground geologic structure in Jeju island where underground air is distributed are lava cave, pyroclastic, open joint, and crushing zone. Such districts are identified to secure an enough airflow when air ventilation layer is to secure 25-35m in depth. In Jeju, Ground air is used for heating greenhouse and fertilizing natural $CO_2$ gas by suppling directly into greenhouse. But the heating method by suppling ground air into greenhouse directly bring about several problem. The occurrence of disease of the crops by high humidity is worried because the underground air which becomes discharge from underground air layer has over 90% relative humidity. The underground air is inadequate in heating for crops which need high temperature heating such as mangos, Hallbong and mandarin orange because the temperature of it is $15{\sim}18^{\circ}C$. Also There is worry where the ventilation loss becomes larger because the air pressure inside greenhouse is high by supplying underground air directly. In this study the heat pump system using underground air as heat source was developed and heating performance of the system was analysed. Heating COP of the system was 2.5~5.0 and rejecting heat into greenhouse and extracting heat from underground air were 40,000~27,000 kcal/h, 30,000~18,000 kcal/h respectively.

  • PDF

Weighted Analysis Method for Estimating the Orientation of Limestone Caves in Korea (가중치를 이용한 국내 석회동굴 발달 방향성 해석법 개발에 관한 연구)

  • Lee, Sang-Kyun;Park, Hyeong-Dong
    • The Journal of Engineering Geology
    • /
    • v.24 no.1
    • /
    • pp.39-52
    • /
    • 2014
  • Limestone caves that consist of main passages and branches are formed by a variety of processes, and have the characteristic of developing with a preferred orientation controlled by discontinuities such as bedding, joints, and faults around the cave. However, it is difficult to analyze a representative orientation from various orientations. To interpret the overall development orientation of limestone caves, this study proposes new development orientation analysis methods, termed the Average Span Ratio Method (ASRM) and the Individual Development Ratio Method (IDRM), using the weighting of persistence. Nine limestone caves in Korea were randomly selected for testing the new methods. The methods show a stronger development orientation for limestone caves than that obtained by traditional methods, which consider only the distribution of development orientations. Based on an analysis of the relationship between the average span and the dip angle of bedding, it is confirmed that shallowly dipping bedding is a major contributor to the expansion of span in limestone caves. In addition, using scan-line survey data acquired in the field, we perform an RMR analysis of stability of the ground around limestone caves.

Ground Subsidence Caused by the Development of Underground Karstic Networks in Limestone Terrain, Taebag City Korea (석회암 분포지에서 터널시공에 따른 지표침하 원인 분석)

  • Lee, Byung-Joo;Park, SungWook;Kim, Dea-Hong;Song, Young-Karb
    • The Journal of Engineering Geology
    • /
    • v.26 no.1
    • /
    • pp.63-70
    • /
    • 2016
  • The aim of this study is the safety and an accident prevention in limestone terrain by the underground tunneling. The geology of the study area consists of a Paleozoic sedimentary sequence dominated by limestone, sandstone, shale, and carbonaceous shale. The sequence gently dips to the northeast but the joint contains steep with variable trend. A significant fracture zone is developed in the limestone and shale beds, sub-parallel to bedding, and follows in part the limestone-sandstone contact. Monitoring of groundwater levels in the area shows marked fluctuations in the water table, which repeatedly rose to a level of -4 m before sinking to -15 m. These cycles occurred in mid-May, 2007 and in early and middle June. The data indicate that these fluctuations were unrelated to rainfall that occurred during the study period. We infer that the fluctuations were associated with the development of underground karstic networks along the deep fracture zone, and overlying ground subsidence is likely related to the rapid sinking of groundwater and the associated strong downward suction force.

Conservation and Management of Lava Tubes in Jeju Island, Korea (제주도 용암동굴의 보존 및 관리 방안에 관한 연구)

  • Kim, Beom-Hoon;Kim, Tae-Ho
    • Journal of the Korean association of regional geographers
    • /
    • v.13 no.6
    • /
    • pp.609-622
    • /
    • 2007
  • This paper examines the lava tubes designated as a natural monument in Jeju Island, and then makes the several suggestions for conserving and managing them. The cave entrances should be scientifically and strictly managed to prevent the deterioration, and to preserve the interior ecosystem, of the lava tubes. The land use and vegetation of the ground surface over the lava tubes should be also systematically managed; the destroyed sand dunes must be recovered for the development of speleothem in the lava tubes, and the plants with deep roots must be removed for the prevention of ceiling collapse. The provincial authorities should manage the ground surface over the lava tubes as a public land to remove the factors threatening the stability of the lava tubes. Since the roads crossing the ground surface are likely to cause the collapse of the lava tubes, new roads bypassing the caves need to be constructed, and warning signs should be also installed at the traverse points. A monitoring system on the cultural properties protection area over the lava tubes could be effectively established by encouraging residents to participate the conservation program of lava tubes. Since the falling blocks from ceilings have been usually observed in the lava tubes, it is urgent to examine their stability. In particular, the dangerous sections must be continuously monitored for taking a quick measure against the collapse. The air environments of lava tubes need to be scientifically analyzed based upon the long-term observations. The lighting equipments must be improved to minimize the green pollution in the lava tubes open to the public. The numbers of visitors should be also controlled to prevent the destruction and contamination of lava tubes caused by a large number of visitors.

  • PDF

Development of underground facility information collection technology based on 3D precision exploration (3차원 정밀탐사 지하시설물 정보 수집 기술 개발)

  • Jisong RYU;Yonggu JANG
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.26 no.4
    • /
    • pp.56-66
    • /
    • 2023
  • Safety accidents are increasing, such as changes in groundwater levels due to construction work or natural influences, or ground cave-ins caused by soil runoff from old water supply and sewage pipes. In addition, underground facility management agencies must make efforts to improve the accuracy of underground information through continuous investigation and exploration in accordance with the Special Act on Enhanced Underground Safety Management. Accordingly, in this study, we defined the configuration of equipment and data processing method to collect 3D precise exploration underground facility information and developed 3D underground facility information collection technology to ensure accuracy of underground facilities. As a result of verifying the developed technology, the horizontal accuracy improved by an average of 6cm compared to the existing method, making it possible to acquire 3D underground facility information within the error range of the public survey work regulations.

Radon concentration measurement at general house in Pusan area (부산지역 일반주택에서의 라돈농도측정)

  • Im, In-Cheol
    • Journal of radiological science and technology
    • /
    • v.27 no.2
    • /
    • pp.29-33
    • /
    • 2004
  • Until early 1980s we have lived without thinking that radon ruins our health. But, scientists knew truth that radon radioactive danger is bedeviling on indoor that we live for a long time. Specially, interest about effect that get in danger and injury for Radon and human body is inactive in our country. Recently, with awareness for Radon contamination, We inform about importance and danger of Radon in some station of the Seoul subway, indoor air of school facilities and We had interest with measure and manages. Usually, Radon gas emitted in base of building enters into indoor through building floor split windage back among radon or indoor air of radon daughter nucleus contamination is increased. Therefore, indoor radon concentration rises as there are a lot of windages between number pipe of top and bottom and base that enter crack from estrangement of the done building floor, underground to indoor. Thus, Radon enters into indoor through architecture resources water as well as, kitchen natural gas for choice etc., but more than about 85% from earth's crust emit. Danger and injury of health by Radon and Radon daughter nucleus that is indicated for cause of lung cancer incerases content of uranium of soil rises specially from inside pit of High area and a mine, cave, hermetical space with house. Safe sub-officer of radon concentration can not know and danger always exists large or small during. So, Important thing reduces danger of lung cancer by lowering concentration of Radon within house and building. Therefore, is thought that need general house Radon concentration measurement, measured Radon concentration monthly using Sintillator radon monitor. Study finding appeared high all underground market 1 year than the ground, and the winter appeared high than the summer. Specially, month that pass over 4pCi in house that United States Environmental Protection Agency advises appeared in underground, and appeared and know Radon exposure gravity by 4 months during 12 months. Therefore, Thinking that establishment and regulation of norm and preparation of reduction countermeasure about Radon are pressing feels, and inform result that measure Radon concentration.

  • PDF

A bibliographic study on medical science ancient period (上古時代) and the era of the old-Korea (古朝鮮時代) (상고시대(上古時代)와 고조선시대(古朝鮮時代)의 의학(醫學)에 관(關)한 문헌적(文獻的) 고찰(考察))

  • Kwon, Hak Cheol;Park, Chan-Guk
    • Journal of Korean Medical classics
    • /
    • v.3
    • /
    • pp.218-247
    • /
    • 1989
  • As mentioned above, I got the next conclusion since I had considered the medical contents of the ancient period(上古時代) and the era of the old-Korea(古朝鮮時代) through several bibliographic records. 1. There were Pung-baeg(風伯), Uh-sa(雨師), Un-sa(雲師) that were the names of the governmental officials during the ancient period of Whan-ung(桓雄). Among them, Uh-sa specially managed the treatment for diseases. When we think of the significance of Pung(風)-which means the winds, Uh(雨)-which means the rain, Un(雲)-which means of clouds, we will find out that the human life will be affected by all kinds of phenomena of the nature. So I can infer that ancestries could prevent and treat diseases with adjusting them tn the changes in the weather. 2. There were five government officials(五事) in the ancient period of Whan-ung(桓雄上古時代). They are Uh-ga(牛加), Ma-ga(馬加), Ku-ga(狗加), Cheo-ga(猪加) and Yang-ga(羊加), and had charges of five important duties. Among them, Cheo-ga was set to a charge of treatment for diseases. So we can notice that there existed people who treated for diseases professionally. When we think of the meanings of Uh(牛)-which intends cows or bulls. Ma(馬)-which intends horses, Ku(狗)-which intends dogs, Cheo(猪)-which intends wild boars and Yang(羊)-which intends sheep, we can see that livestocks would be raised at that time, and they came to have more chances to digest meat. Since the digestion of meat became to be a burden on the stomach and the intestines, it might cause a lot of indigestive troubles. 3. When I compared Tan-gun Pal-ga(檀君八加) with the Oh-ga(五加) in the ancient period of Whan-ung(桓雄上古時代), I could tell that the community of Tan-gun's period is more advanced and specialized than one of Whan-ung's. When I think of the next sentence ; "The Prince Imperial, Bu-u(夫虞) become to be a Ro-ga(鷺加), who treat for diseases professionally.", I am sure that the treatment for diseases was more importment than any other things, because he was the third son of Tan-gun(檀君). 4. According to Tan-gun(檀君) mythology, Whan-ung(桓雄) came down from the heaven of the pure Yang(純陽) to the earth and then changed into a man who had had more Yang(陽) than Yin(陰). And a bear came up from the underground(or the cave) to the ground and then changed into a women who had had more Yin(陰) than Yang(陽). So both of them became to hold together. This story implicated that ancestors had taken a serious view of each of them, namely the ancestors didn't give the ascendance to the one side of them, and made much account of the mutual harmony. So I am sure that this fact coincided with the basic theories of oriental medical science. To refer to two proverbs of Tan-gun mythology that are "Ki-Sam-Chil-Il(忌三七日)" which means caring for twenty one days, and "Pul-Gyon-Il-Gwang-Baeg-Il(不見日光百日)" which means keeping indoors for one hundred days, I can tell you that "twenty-one-day" involves the principle of the birth of life, and "one-hundred-day" contains a preparatory period or the period of death to bear another life. 5. From the medical stuff, such as wormwood(艾), garlic(蒜), or wonder-working herbage(靈草), that had been written at the bibliographic papers of the ancient period(上古時代) and the era of the old-Korea(古朝鮮時代), I consider that many people might get a lot of women's diseases, indigestive troubles, and other diseases that were caused by the weakness, but with using various spices, such as the leaves of water pepper(蔘), they could prevent the occurrance of all kinds of diseases previously. So I regard this treatment as the medicine from food. 6. One of the sayings at Nae-gyong(內經) is that "The stone accupuncture(砭石) came from the orient." We can see both "wonder-wor-king wormwood(靈草)" and "dried wormwood(乾艾)" in the several bibliographic papers of the ancient history of the old-Korea(朝鮮上古史). From these records, I can be convinced that ancestors would utilize the acupuncture(針) and the moxa cautery(灸) to cure a patient of a disease. 7. Even though someone claimed that the book, "medical science and chemistry(醫學化學)" and "medical treatment(醫學大方)" had had been written during the ancient period of the old-Korea(上古朝鮮時代), such a fact can't have been ascertained historical evidence. But it has been handed down that there existed the original phonetic alphabet, such as the "Ka-Im-To alphabet(加臨土文字)" at that time. The terms about the diseases, which had been occurred at the community of the old-Korea(古朝鮮地域), were recorded fragmentarily at other records after that time. The origin of confucianism came from the race of the eastern barbarians, and Tae-Ho-Pok-Hi(太嗅伏義) and the king. Sun(舜) came from the eastern barbarians, too. The divination of tortoise shells at the country of Un(殷) is another from which was developed at the eastern barbarians' fortune-telling of animal bones. From these facts, I can infer that, by all means, they might record the medical knowledge which had been stored for thousands of years while contacting with china directly.

  • PDF