• Title/Summary/Keyword: Volcanic stones

Search Result 8, Processing Time 0.023 seconds

An Experimental Study on Development of Artificial Reefs Using Volcanic Stones for Marine Forests (용암석을 사용한 해중림 조성용 인공 조초 개발에 관한 실험적 연구)

  • Hong, Chong-Hyun;Ghoa, Jong-Hun
    • Journal of Ocean Engineering and Technology
    • /
    • v.22 no.3
    • /
    • pp.103-108
    • /
    • 2008
  • Topics discussed in this paper are engineering design of artificial reefs, design considerations of compressive strength and pH, materials of silica fume concrete and volcanic stones for reef construction, and field monitoring of artificial reefs. Six artificial reefs were deployed offshore at Biyangdo in July 2006, and succession patterns on the reefs were investigated bimonthly from July 2006 to October 2007. The spore-bag method, which has been widely used in Korea for the attachment of seaweed on artificial reefs, was applied to the developed reefs using the kelp Ecklonia cava, which is the dominant species in Jeju, and recruitment and growth patterns were observed.

Substrate removal characteristics in anaerobic filter using volcanic stones (화산석(火山石)을 이용(利用)한 혐기성고정상(嫌氣性固定床)에 있어서 기질(基質)의 제거특성(除去特性))

  • Eom, Tae-Kyu;Kim, Young-Chur;Kim, Kyung-Ho
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.7 no.1
    • /
    • pp.46-53
    • /
    • 1993
  • This study was carried out to examine substrate removal characteristics with the variation of the hydraulic retention time in an anaerobic filter. The feed concentration of synthetic wastewater used in the experiment was $10,000mg/l$ glucose. As media, the porosity of volcanic stones in Jeju island were 76%. The conditions of the experiment were as follows; HRT ranging from 1 day to 3 day, loading rates ranging from 3.33kg $COD_{er}/void\;m^3.day$ to 10kg $COD_{er}/void\;m^3.day$ and a temperature $35^{\circ}C$. Based on the results of the experiments, the COD removal efficiency was 98~99% in $COD_{er}$ method with loading rates ranging from 3.33kgCOD/void $m^3.day$ to 10kg COD/void $m^3.day$ and HRT ranging from 1day to 3 day. The produced quantity of gas equivalant to a porosity volume was $1.332~3.756Nm^3/void\;m^3.day$. The relationship between $COD_{er}$ loading rates and gas produced quantity equivalant to a porosity volume was well fitted with the equation of $Nm^3/void\;m^3.day{\cdot}=0.359L_0+0.179$($L_0=COD$ loading rate). Judging from the removal efficiency in this experiment, We concluded that anaerobic filter using Volcanic stones is one of improved and effective. As media, practical value of volcanic stones is sufficient.

  • PDF

Source Area of the Rocks Using the West Stone Pagoda of Gameunsaji Temple Site, Korea (감은사지삼층석탑(서탑)에 사용된 석재 공급지에 대한 연구)

  • Jwa, Yong-Joo;Kim, Kun-Ki;Ko, Seok-Bae;Kim, Jong-Sun
    • The Journal of the Petrological Society of Korea
    • /
    • v.15 no.3 s.45
    • /
    • pp.128-138
    • /
    • 2006
  • The west stone pagoda of Gameunssji temple site (National Treasure No. 112) has been damaged mainly by fracture, exfoliation and granular disintegration. In this study, the source area of the rocks using the west stone pagoda was examined in terms of petrological feature, magnetic susceptibility, and ${\gamma}-ray$ spectrometer. The stones include abundant crystal fragments of biotite, quartz and feldspars in the fine-grained matrix; they are petrographically discriminated to vitric-crystal tuff or crystal tuff. Measured magnetic susceptibility values are of from 10 to 20 $({\times}10^{-3}\;SI\;unit)$. From the ${\gamma}-ray$ spectrometer measurement K, eU, and eTh contents of the stones are about 3%, 0 to 8ppm, and 9 to 18 ppm, respectively. These features are used as indicators to presume the source area of the stones. Comparing the petrographical and chemical characteristics between the stones of the west stone pagoda and the country rocks near the Gameunsaji temple site, it is suggested that the most similar country rock to the stones could be dacitic volcanic rocks of the Beomgokri group in the Waeup basin. The Beomgokri group is lithostratigraphically divided into Waeupri tuff, Yongdongri tuff and Beomgokri volcanic rocks. Among the three rocks, the crystal tuff of the Beomgokri volcanic rocks seems likely to have been the source rock of the stones of the west stone pagoda.

Alkali- Aggregate Reaction of the Crushed Stones Depending on the ASTM C 227 and C 1260 Test Method (ASTM C 227과 ASTM C 1260에 따른 쇄석 골재의 알칼리-골재 반응성)

  • 전쌍순;이효민;진치섭;황진연;이진성
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2003.05a
    • /
    • pp.13-18
    • /
    • 2003
  • The concrete structure can be easily damaged due to alkali-aggregate reaction. The alkali-aggregate reaction is a reaction between the alkalies(K or Na) in cement and an unstable mineral of the aggregates. There are several test methods to identify alkali reactivity of aggregates. In general, crushed stones are tested by petrographic examination, chemical method and 모르타르 바 method. This study tested alkali-aggregate reactivity of crushed stones that has different rock types such as granitic, volcanic, metamorphic and sedimentary rocks. Samples are collected from 12 local aggregate production companies. Alkali-reactivity of various rock types was evaluated by using ASTM C 227 and C 1260, and compared the test results of two test methods.

  • PDF

Mineralogical Characteristics and Designation of Key Beds for the Effective Surveys of the Jeonnam Pyrophyllite Deposits (전남일원 납석광상의 광물학적 특성과 효과적 탐사를 위한 Key Beds의 선정)

  • Yoo, Jang-Han;Kim, Yong-Ug;Lee, Gill-Jae
    • Journal of the Mineralogical Society of Korea
    • /
    • v.22 no.4
    • /
    • pp.297-305
    • /
    • 2009
  • Ores of the Jeonnam pyrophyllite province mainly consist of not only pyrophyllite but also kaolinite, and they usually contain minor amounts of muscovite and quartz. We usually call them as porcelaneous stones which usually show lower grade characteristics in the viewpoint of Korean nonmetallic industries. Mineralogical studies for the ores and their intimate formations revealed that another kind of clay minerals could have been produced from the volcanic sediments with similar ages and compositions. Corundum is commoner than the diaspore in the pyrophyllite deposits, and so diaspore can be regarded as one of temporary minerals from which corundum would be finally formed. Kaolinite deposits contain neither diaspore nor corundum, but alunites produced by an advanced argillic alteration are often observed in the upper portions of the kaolin ores. The lowest formation interbedded with pyrophyllite and/or kaolinite ores usually contain purple tuff bed on the uppermost part, and in ascending order, siliceous formation, fine ash tuff and lapillistone are found in the study areas. As ages are becoming younger, amounts of pyrophyllite and kaolinite are radically decreased, or disappeared completely. On the other hand, content of muscovite is slightly increased, and those of plagioclase feldspars and quartz are found to have been preserved from the original rocks during alteration process. Most of ore bodies show rather well bedded formations which are easily discernable in the outcrops, but more effective discremination is desirable where rather massive ores exist. Siliceous beds and purple tuff ones on the upper part of ore bodies would be useful as marker horizons or key beds which have distinct lithologies and extensions.

Geology and Distribution of Crushed Aggregate Resources in Korea (국내 골재석산의 분포와 유형 분석)

  • Hong Sei Sun;Lee Chang Bum;Park Deok Won;Yang Dong Yun;Kim Ju Yong;Lee Byeong Tae;Oh Keun Chang
    • Economic and Environmental Geology
    • /
    • v.37 no.5
    • /
    • pp.555-568
    • /
    • 2004
  • The demand of aggregate resources in Korea has been increased with a rapid economic growth since the 1980s. About 25% of the total aggregate production is derived from riverine aggregates, 20% to 25% from marine sands, 40% to 45% from crushed aggregate and the rest 5% to 15% from old fluvial deposits. The abundance of crushed coarse aggregates varies in the uniform distribution of country, but in general it can be concentrated in the most densely populated areas, five main cities. Typical rock types of the Korean crushed stones are classified as plutonic rocks of 27%, metamorphic rocks of 32%, sedimentary rocks and volcanic rocks of 18%, respectively. The most abundant coarse aggregate used in the country is obtained from granite (25% of total) and subordinately gneiss (20%), sandstone (10%) and andesite (10%). Although rock types using as dimension stone are only fifteen, those as aggregate amount up to twenty nine rocks. These rocks consist of plutonic rocks such as granite, syenite, diorite, aplite, porphyry, felsite. dike and volcanic rocks such as rhyolite, andesite, trachyte, basalt, tuff, volcanic breccia and metamorphic rocks such as gneiss, schist, phyllite, slate, meld-sandstone, quartzite, hornfels, calc-silicate rock, amphibolite. And sandstone, shale, mudstone, conglomerate, limestone, breccia, chert are main aggregate sources in tile sedimentary rocks. The abundance of plutonic rocks is the highest in Chungcheongbuk-do, and decreases as the order of Jeollabuk-do, Gangwon-do and Gyeonggi-do. In Jeollanam-do, volcanic aggregates occupy above 50%, on the contrary sedimentary aggregates are above 50% in Gyeongsangnam-do.

Interdisciplinary Study on Bronze Age Artifacts in Midwestern Korea: Material Characteristics and Provenance Presumption for Stone Artifacts of the Sinsongri Site in Seosan (한반도 중서부 청동기시대 유물의 융합과학적 연구: 서산 신송리유적 석기의 재질특성과 산지추정)

  • Lee, Chan Hee;Kim, Ran Hee;Eo, Eon Il
    • Journal of Conservation Science
    • /
    • v.30 no.2
    • /
    • pp.205-217
    • /
    • 2014
  • The stone artifacts in Bronze age from the Sinsongri sites in Seosan, Korea were studied on material characteristics and provenance presumptions. The use and rock names of the artifacts are a stone before processing, two semifinished stone arrowheads and a grinding stone plate by slates. In addition, there is semifinished stone arrowhead by andesitic rocks. The slate could be observed easily around the site, and the andesitic rock could be confirmed typical occurrences of the all kinds of rocks around the Kanwoldo and Hwangdori, Anmyun area above 10km from the site. As a result of analysis which is comparing between stone artifacts and same kinds of raw material rocks, the stone artifacts made by slates have similar lithology and geochemical characteristics however, the stone artifacts made by andesitic rocks are found a some different part of characteristics to the same kind of raw material rocks. Comparing of major, rare earth, compatible and incompatible elements about stones artifacts made by slates and by the same kinds of raw material rocks have same geochemical patterns. However stone artifacts made by andesites and the raw material rocks are confirmed some differences of geochemistry. Therefore the slate stone artifacts in Sinsongri site suggest that these are domestic-type which are made of the rocks around the site, and it was understood that the andesitic stone artifacts are foreign-type which need to get more geological survey and study about different volcanic artifacts of the site around the area.

Archeological Quest on the Origin and Formation of the Stone Needle in the Korean Peninsula (폄석(砭石)의 한반도 기원과 형성에 관한 연구)

  • Yim, Yong-Soo;Sohn, In-Chul;Kang, Yeon-Seok;Kim, Seong-Chul;Kim, Jae-Hyo
    • Korean Journal of Oriental Medicine
    • /
    • v.15 no.2
    • /
    • pp.51-61
    • /
    • 2009
  • Objective: Much has been known that the systematical theory of acupuncture was developed from stone needle as therapeutic tools for orthopedic diseases in ancient times. Stone needle is very old therapeutic method like moxibustion and has been recognized that it was developed since the Stone Age in China so far. In the present study, it was examined for the origination and formation of stone needle based on stone relics of the Stone Age in Korean Peninsular, the medical and geographical literatures. Materials and methods: The facts of stone needle was examined and arranged on the ancient medical or geographical literatures such as The Yellow Emperor's Canon Internal Medicine, Shanhaijing as an ancient geographical book, etc. The clan societies and family related to an origination of stone needle was chased together with their cultural characteristics and origination. The stone relics which have been digged out of historic sites in the North-East Asia were examined for a relevance to stone needle. Results: In The Yellow Emperor's Canon Internal Medicine, it was referred to the stone needle that originated from a fishery zone related to the east coast district in North-East Asia. Through the examination of Shan Hai Jing as an ancient geographical book and its historical reviews, a Go-yi clan society who keep Go's family tree dealt well with the stone needle and jewels including jade in the North-East Asia before the publication periods of The Yellow Emperor's Canon Internal Medicine, and is comprised in the culture of Dong-yi clan society but not the Chinese culture. The obsidian stones, which have been digged out of historical sites in the North-East Asia since the Stone Age, are originated from volcanic areas combined with seashore that seems to be Baekdu mountain district in Korea and Kyushu district in Japan. Furthermore, obsidian stone tools which were found out at Laodung peninsula and the Korean peninsula are archeologically similar to the stone needle with regards to the shape, size and dual-use. In addition, specific obsidian stone tools have been used in orthopedic surgery as well-crafted obsidian blades have a cutting edge up to five times sharper than high-quality steel surgical scalpels. Conclusion: The origin of obsidian stone needle is well corresponded to the explanation about that of the stone needle. It is suggested that the stone needle which influenced in completion of acupuncture and Meridian theory in China seems to be an obsidian stone, and distribution of obsidian stone needle has been closely connected to Dong-yi clan society which are lived in the North-East Asia including Baekdu-mountain district.

  • PDF