• Title/Summary/Keyword: Volcanic observation

Search Result 40, Processing Time 0.027 seconds

Developing Interactive Simulator for Predicting Volcanic Ash (실시간 대화형 화산재 확산 예측 시스템 개발)

  • Kim, Hae-Dong;Lee, Ho-Man
    • Journal of Environmental Science International
    • /
    • v.23 no.3
    • /
    • pp.527-532
    • /
    • 2014
  • According to the analysis of volcanic observation data around Korean peninsula, the activities of volcano increase continuously. For example, the volcanic eruption of Mt. Sakurajima is an example, and Mt. Baekdu can be another example potentially. In these regards, developing unified system including realtime prediction and 3D visualization of volcano ash are important to prepare the volcanic disaster systematically. In this technical report, an interactive simulator embedding dispersion algorithm and 3D visualization engine is developed. This system can contribute to the realtime prediction of volcanic disaster scientifically.

Monitoring of the Volcanic Ash Using Satellite Observation and Trajectory Analysis Model (인공위성 자료와 궤적분석 모델을 이용한 화산재 모니터링)

  • Lee, Kwon-Ho;Jang, Eun-Suk
    • Korean Journal of Remote Sensing
    • /
    • v.30 no.1
    • /
    • pp.13-24
    • /
    • 2014
  • Satellite remote sensing data have been valuable tool for volcanic ash monitoring. In this study, we present the results of application of satellite remote sensing data for monitoring of volcanic ash for three major volcanic eruption cases (2008 Chait$\acute{e}$n, 2010 Eyjafjallaj$\ddot{o}$kull, and 2011 Shinmoedake volcanoes). Volcanic ash detection products based on the Moderate Resolution Imaging Spectro-radiometer (MODIS) observation data using infrared brightness temperature difference technique were compared to the forward air mass trajectory analysis by the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. There was good correlation between MODIS volcanic ash image and trajectory lines after the volcanic eruptions, which support the feasibility of using the integration of satellite observed and model derived data for volcanic ash forecasting.

Monitoring Techniques for Active Volcanoes (활화산의 감시 기법에 대한 연구)

  • Yun, Sung-Hyo;Lee, Jeong-Hyun;Chang, Cheol-Woo
    • The Journal of the Petrological Society of Korea
    • /
    • v.23 no.2
    • /
    • pp.119-138
    • /
    • 2014
  • There are various ways to monitor active volcanoes, such as the method of observing the activity of a volcano with the naked eye, the method of referring to the past eruptive history based on the historic records and the method of monitoring volcanoes by using observation equipment. The most basic method from the observation equipment-using methods to monitor volcanoes is seismic monitoring. In addition to this, the ways to monitor volcanoes are as follows: resonance observation which may be effective to remove artificial noises from the seismic activities that are recorded in the seismograph, ground deformation by using precision leveling, electronic distance measurement, tiltmeter, GPS, and InSAR observation method, volcanic gas monitoring, hydrologic and meteorological monitoring, and other geophysical monitoring methods. These monitoring methods can make volcanic activities effectively monitored, determine the behavior of magmas in magma chambers and help predict the future volcanic eruptions more accurately and early warning, thus, minimize and mitigate the damage of volcanic hazards.

Volcano Monitoring Using Earthquakes (지진을 이용한 화산감시)

  • Han, Arim;Park, Iseul;Kim, Ki Young
    • Geophysics and Geophysical Exploration
    • /
    • v.16 no.4
    • /
    • pp.268-274
    • /
    • 2013
  • Continuous seismic observation of volcanic earthquakes related to migration of magma or gas, is one of the most important methods used to monitor active volcanoes. In this review paper, we introduce the characteristics of volcanic earthquakes and their classification based on locations of foci, waveforms, frequencies, lithology, and source mechanisms. We also present some examples of successful warnings of volcanic eruptions and the present status of some observations of volcanic earthquakes in Japan, the United States, Italy, and New Zealand.

Monitoring and Forecasting the Eyjafjallajökull Volcanic Ash using Combination of Satellite and Trajectory Analysis (인공위성 관측자료와 궤적분석을 이용한 Eyjafjallajökull 화산재 감시와 예측)

  • Lee, Kwon Ho
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.30 no.2
    • /
    • pp.139-149
    • /
    • 2014
  • A new technique, namely the combination of satellite and trajectory analysis (CSTA), for exploring the spatio-temporal distribution information of volcanic ash plume (VAP) from volcanic eruption. CSTA uses the satellite derived ash property data and a matching forward-trajectories, which can generate airmass history pattern for specific VAP. In detail, VAP properties such as ash mask, aerosol optical thickness at 11 ${\mu}m$ ($AOT_{11}$), ash layer height, and effective radius from the Moderate Resolution Imaging Spectro-radiometer (MODIS) satellite were retrieved, and used to estimate the possibility of the ash forecasting in local atmosphere near volcano. The use of CSTA for Iceland's Eyjafjallaj$\ddot{o}$kull volcano erupted in May 2010 reveals remarkable spatial coherence for some VAP source-transport pattern. The CSTA forecasted points of VAP are consistent with the area of MODIS retrieved VAP. The success rate of the 24 hour VAP forecast result was about 77.8% in this study. Finally, the use of CSTA could provide promising results for VAP monitoring and forecasting by satellite observation data and verification with long term measurement dataset.

An Experimental Study on the Application of Porous Scoria Concrete to Artificial Reefs for Soft Coral (연산호 육성용 어초 개발을 위한 송이 다공성 콘크리트의 적용성에 관한 실험적 연구)

  • HONG CHONG-HYUN;KIM MOON-HOON;KIM SEOK-CHEL;PARK SUNG-BAE;Ryu SEONG-PIL
    • Journal of Ocean Engineering and Technology
    • /
    • v.19 no.4 s.65
    • /
    • pp.28-34
    • /
    • 2005
  • In the study application of volcanic scoria concrete to artificial reefs is investigated. Volcanic scoria is a natural volcanic product that shows light weight, mil/i-porous, and far-infrared irradiation characteristics. The properties of volcanic scoria concrete using Jeju scoria aggregate are evaluated by conducting a comprehensive series of tests on strength and void ratio. It is concluded that the volcanic scoria concrete has the sufficient strength of 4MPa-13MPa and adequate void ratio of $12\%-35\%$ to be accepted as artificial reef concrete. The field experiments are performed through observation by scuba diver's at the Seogwipo coast. Porous specimen and plane concrete specimen are prepared for comparison purposes. Seasonal changes of soft coral on the two series of test specimens were have been observed from Apr. 9, 2004 to Mar. 18, 2005. The soft coral is well grown on the porous specimen however there are no significant changes on the conventional plain concrete specimen. Thus it is concluded that the volcanic scoria concrete is highly suitable as artificial reef concrete.

Gravity and Magnetic Surverys for Volcanic Rocks in Yeoncheon Area, kyonggi-do (경기도 인천지역 분포하는 화산암류에 대한 중력 및 자력 탐사 연구)

  • 박혁진
    • Economic and Environmental Geology
    • /
    • v.32 no.6
    • /
    • pp.645-651
    • /
    • 1999
  • The gravity and magnetic measurements have been obtained from 34 stations with 50m intervals along the survey line positioned between Jangtanri and sindapri for studying subsurface geology and structures of the volcanic rocks in Yeoncheon area. The Bouguer gravity and magnetic anomaly values were evaluated from the reduction of the field observation, and then interpreted by Nettleton's method and maximum-pepth rules, are approximately 160m based on magnetic data and 135m based on gravity data. High Bouguer gravity anomaly zone between 0m in Jangtanri and 900m along the survery line, is caused by thick and high density, older dasalt which is positioned beneath jijangbong tuff breccia, and this result corresponds to the interpretation result based on magnetic anomly. Lower gravity and magnetic anomaly zones ariund 900m are caused by between 1300m and 1550m are caused by high density of Quarternary basalt exposed in the surface, and lower gravity and magnetic anomalies at 200m and 1250m are caused by faults.

  • PDF

The History of Volcanic Hazard Map (화산위험지도의 역사)

  • Yun, Sung-Hyo;Chang, Cheolwoo;Ewert, John W.
    • The Journal of the Petrological Society of Korea
    • /
    • v.27 no.1
    • /
    • pp.49-66
    • /
    • 2018
  • Volcano hazard mapping became a focus of scientific inquiry in the 1960s. Dwight Crandell and Don Mullineaux pioneered the geologic history approach with the concept of the past is the key to the future, to hazard mapping. The 1978 publication of the Mount St. Helens hazards assessment and forecast of an eruption in the near future, followed by the large eruption in 1980 demonstrated the utility of volcano hazards assessments and triggered huge growth in this area of volcano science. Numerical models of hazardous processes began to be developed and used for identifying hazardous areas in 1980s and have proliferated since the late 1990s. Model outputs are most useful and accurate when they are constrained by geological knowledge of the volcano. Volcanic Hazard maps can be broadly categorized into those that portray long-term unconditional volcanic hazards-maps showing all areas with some degree of hazard and those that are developed during an unrest or eruption crisis and take into account current monitoring, observation, and forecast information.

Initial Evaluation using Geochemical Data to infer Tectonic Setting of Mt. Baekdu/Changbaishan Volcano (백두산 화산의 지체구조 추론을 위한 지구화학적 데이터를 이용한 기초 평가)

  • Yun, Sung-Hyo;Chang, Cheolwoo;Pan, Bo
    • Journal of the Korean earth science society
    • /
    • v.43 no.1
    • /
    • pp.128-139
    • /
    • 2022
  • This study aimed to investigate the tectonic setting of the volcanic edifice at Mt. Baekdu by analyzing petrochemical characteristics of Holocene felsic volcanic rocks distributed in the Baekdusan stratovolcano edifice and summit of the Cheonji caldera rim, as well as Pleistocene mafic rocks of the Gaema lava plateau and Changbaishan shield volcano edifice. During the early eruption phases, mafic eruption materials, with composition ranging from alkali basalt to trachybasalt, or from subalkaline (tholeiitic) basalt to basaltic andesite formed the Gaema lava plateau and Changbaishan shield volcanic edifice, whereas the Baekdusan stratovolcano edifice and Holocene tephra deposits near the summit of the Cheonji caldera comprises trachytic and rhyolitic compositions. Analysis results revealed bimodal compositions with a lack of 54-62 SiO2, between the felsic and mafic volcanic rocks. This suggested that magmatic processes occurred at the locations of extensional tectonic settings in the crust. Mafic volcanic rocks were plotted in the field of within-plate volcanic zones or between within-plate alkaline and tholeiite zones on the tectonic discrimination diagram, and it was in good agreement with the results of the TAS diagram. Felsic volcanic rocks were plotted in the field of within-plate granite tectonic settings on discrimination diagrams of granitic rocks. None of the results were plotted in the field of arc islands or continental margin arcs. The primitive mantle-normalized spider diagram did not show negative (-) anomalies of Nb and Ti, which are distinctive characteristics of subduction-related volcanic rocks, but exhibited similar patterns of ocean island basalt. Trace element compositions showed no evidence of, magmatic processes related to subduction zones, indicating that the magmatic processes forming the Baekdusan volcanic field occurred in an intraplate environment. The distribution of shallow earthquakes in this region supports the results. The volcanic rocks of the Baekdusan volcanic field are interpreted as the result of intraplate volcanism originating from the upwelling of mantle material during the Cenozoic era.

Predicting the extent of the volcanic ash dispersion using GOCI image and HYSPLIT model - A case study of the 17 Sep, 2013 eruption in SAKURAJIMA volcano - (GOCI 위성영상과 HYSPLIT 모델을 이용한 화산재 확산경로 예측 - 2013년 9월 17일 분화된 사쿠라지마 화산을 중심으로 -)

  • Lee, Seul-Ki;Ryu, Geun-Hyeok;Hwang, Eui-Hong;Choi, Jong-Kuk;Lee, Chang-Wook
    • Korean Journal of Remote Sensing
    • /
    • v.30 no.2
    • /
    • pp.303-314
    • /
    • 2014
  • Mt. SAKRAJIMA in southern Kagosima, japan is one of the most active volcanoes in the world. On 18 August 2013, the SAKRAJIMA volcano recently went into the largest scaled eruption with a huge plume of volcanic ash. Therefore, the concern arises if this considerable amount of ashes might flow into the Korea peninsula as well as Japan. In this paper, we performed numeric experiment to analyze how volcanic product resulted from the SAKRAJIMA volcano has impacted on Korea. In order to predict the spread pathway of ash, HYSPLIT model and UM data has been used and 17th September 2013 has been selected as observation date since it is expected that the volcanic ash would flow into the South Korea. In addition, we have detected ash dispersion by using optical Communication, Ocean and Meteorological Satellite- Geostationary Ocean Color Imager (COMS-GOCI) images. As the results, we come to a very satisfactory conclusion that the spread pathway of volcanoes based on HYSPLIT model are matched 63.52 % with ash dispersion area detected from GOCI satellites image.