• Title/Summary/Keyword: Volcanic hazards

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The History of Volcanic Hazard Map (화산위험지도의 역사)

  • Yun, Sung-Hyo;Chang, Cheolwoo;Ewert, John W.
    • The Journal of the Petrological Society of Korea
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    • v.27 no.1
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    • pp.49-66
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    • 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.

Selecting Hazardous Volcanoes that May Cause a Widespread Volcanic Ash Disaster to the Korean Peninsula (한반도에 광역화산재 재해를 발생할 수 있는 위험화산의 선정)

  • Yun, Sung-Hyo;Choi, Eun-Kyeong;Chang, Cheolwoo
    • Journal of the Korean earth science society
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    • v.37 no.6
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    • pp.346-358
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    • 2016
  • This study built the volcano Data Base(DB) of 289 active volcanoes around the Korean Peninsula, Japan, China (include Taiwan), and Russia Kamchatka area. Twenty nine more hazardous volcanoes including Baekdusan, Ulleungdo and 27 Japanese volcanoes that can cause a widespread ash-fall on the Korean peninsula by potentially explosive eruption were selected. This selection was based on the presence of volcanic activity, whether or not containing dangerous explosive eruption rock types, distance from Seoul, and volcanoes having Plinian eruption history with volcanic explosivity index (VEI) 4 or more. The results of this study are utilized for screening high-risk volcanoes that may affect the volcanic disaster caused by a widespread fallout ash. By predicting the extent of spread of ash caused by these hazardous volcanic activities and by analyzing the impact on the Korean peninsula, we suggest that it should be used for helping to predict volcanic ash damages and conduct hazards mitigation research as well.

INTERACTIVE GEOLOGICAL HAZARD MAPS USING GEOHZARDVIEW

  • Bandibas, Joel;Wakita, Koji;Katou, Hirokazu
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.522-524
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    • 2003
  • This paper presents the interactive method of showing geological hazard maps and other related information using the new GIS software developed at the Geological Survey of Japan. The main purpose of the software is to easily provide information about geological hazards to a wide range of users. The software incorporates spatial and a-spatial data to interactively present the time, locations and extent of occurrence of geological hazards and other related information. Queries for hazard information can be easily done. Simulations of the occurrence of a particular geological event like the spread of volcanic ash during major volcanic eruptions can also be easily shown.

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INVESTIGATION OF BAIKDU-SAN VOLCANO WITH SPACE-BORNE SAR SYSTEM

  • Kim, Duk-Jin;Feng, Lanying;Moon, Wooil-M.
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.148-153
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    • 1999
  • Baikdu-san was a very active volcano during the Cenozoic era and is believed to be formed in late Cenozoic era. Recently it was also reported that there was a major eruption in or around 1002 A.D. and there are evidences which indicate that it is still an active volcano and a potential volcanic hazard. Remote sensing techniques have been widely used to monitor various natural hazards, including volcanic hazards. However, during an active volcanic eruption, volcanic ash can basically cover the sky and often blocks the solar radiation preventing any use of optical sensors. Synthetic aperture radar(SAR) is an ideal tool to monitor the volcanic activities and lava flows, because the wavelength of the microwave signal is considerably longer that the average volcanic ash particle size. In this study we have utilized several sets of SAR data to evaluate the utility of the space-borne SAR system. The data sets include JERS-1(L-band) SAR, and RADARSAT(C-band) data which included both standard mode and the ScanSAR mode data sets. We also utilized several sets of auxiliary data such as local geological maps and JERS-1 OPS data. The routine preprocessing and image processing steps were applied to these data sets before any attempts of classifying and mapping surface geological features. Although we computed sigma nought ($\sigma$$^{0}$) values far the standard mode RADARSAT data, the utility of sigma nought image was minimal in this study. Application of various types of classification algorithms to identify and map several stages of volcanic flows was not very successful. Although this research is still in progress, the following preliminary conclusions could be made: (1) sigma nought (RADARSAT standard mode data) and DN (JERS-1 SAR and RADARSAT ScanSAR data) have limited usefulness for distinguishing early basalt lava flows from late trachyte flows or later trachyte flows from the old basement granitic rocks around Baikdu-san volcano, (2) surface geological structure features such as several faults and volcanic lava flow channels can easily be identified and mapped, and (3) routine application of unsupervised classification methods cannot be used for mapping any types of surface lava flow patterns.

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Fragility Assessment of Agricultural Facilities Subjected to Volcanic Ash Fall Hazards (농업시설물에 대한 화산재 취약도 평가)

  • Ham, Hee Jung;Choi, Seung Hun;Lee, Sungsu;Kim, Ho-Jeong
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.27 no.6
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    • pp.493-500
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    • 2014
  • This paper presents findings from the assessment of the volcanic ash fragility for multi-hazard resisting vinyl greenhouse and livestock shed among the agricultural facilities. The volcanic ash fragility was evaluated by using a combination of the FOSM (first-order second-moment) method, available statistics of volcanic load, facility specifications, and building code. In this study, the evaluated volcanic ash fragilities represent the conditional probability of failure of the agricultural facilities over the full range of volcanic ash loads. For the evaluation, 6 types(ie., 2 single span, 2 tree crop, and 2 double span types) of multi-hazard resisting vinyl greenhouses and 3 types(ie., standard, coast, and mountain types) of livestock sheds are considered. All volcanic ash fragilities estimated in this study were fitted by using parameters of the GEV(generalized extreme value) distribution function, and the obtained parameters were complied into a database to be used in future. The volcanic ash fragilities obtained in this study are planning to be used to evaluate risk by volcanic ash when Mt. Baekdu erupts.

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
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    • v.23 no.2
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    • pp.119-138
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    • 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.

The 2014 Eruption and Precursors of Ontake Volcano, Japan (일본 온타케 화산의 2014년 분화와 전조현상)

  • Yun, Sung-Hyo;Lee, Jeong-Hyun;Chang, Cheol-Woo
    • The Journal of the Petrological Society of Korea
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    • v.23 no.4
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    • pp.405-418
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    • 2014
  • Ontake Volcano, Japan, began to erupt without any precursors on September 27, 2014, at 11:52 AM, and it caused many losses of life. Although Japan's preparation manual and prevention for volcanic eruptions and volcanic hazards has been well established, it could not prevent damage due to the sudden eruption of the volcano. Soon after the eruption, however, Japan Meteorological Agency (JMA) led many organizations and institutions, including JMA's Volcanic Eruption Prediction Liaison Council, Meteorological Research Institute (MRI) and National Agriculture and Food Research Organization and they understood the eruption situation quickly and shared the information based on their close cooperation and contact systems. Through these efforts, JMA published the unified result to the public, informing the public of the situation around the volcano and about the eruption and of how the residents and climbers around the volcano should react to the volcanic hazards caused by the eruption. The Korean Government can learn how to respond to a future eruption of a volcano, such as Mt. Baekdu which has the potential to erupt in the foreseeable future.

The Framework of Aeronautical Information System for Volcanic Ash Hazard Management (화산재대응시스템을 위한 항공교통정보 프레임워크)

  • Nam, Doohee;Lee, Jinsun;Lee, Sangsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.16 no.1
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    • pp.166-175
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    • 2017
  • Hazardous volcanic activity will continue to occur in the ring of fire, a major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur. and, because of rising populations, development pressures, and expanding national and international air traffic over volcanic regions, risks to life and property through exposure to volcano hazards continue to increase. During an eruption, volcanic contamination can reach and exceed the cruising altitudes of turbine-powered aircraft, among others, within minutes and spread over vast geographical areas within a few days. Volcanic ash can affect the operation of aircraft at aerodromes. Volcanic ash deposition at an aerodrome, even in very small amounts, can result in the closure of the aerodrome until all the deposited ash has been removed. In this study, air traffic information framework is presented along with algorithms to define affected routes, waypoints and airports using GIS geometry analysis.