5:15 PM - 6:45 PM
[SVC27-P04] The Patterns in Large Volcanic Eruptions identified by Eruption Sequence Database
Keywords:volcanic eruption, large volcanic eruption, volcanic disaster mitigation
A significant volcanic eruption poses a formidable social risk to communities near volcanoes. Although current scientific knowledge offers insights into the physical mechanisms underlying such eruptions, it falls short of predicting future events with precision. To address this gap, we have undertaken a comprehensive review, compiling over 1,400 events and observations from a wide range of literature and documents about more than 20 major volcanic eruptions worldwide. This effort has culminated in creating the "Eruption Sequence Database (ESDB)" hosted on the GSJ-AIST website to enhance our understanding and forecasting capabilities of volcanic phenomena.
To decipher the complex dynamics of volcanic activity, we have pioneered a structured methodology known as the Volcanic Unrest Classification (VUC). This new approach assigns a numerical value, ranging from 0 to 7, to each event and observation, correlating directly to the severity of the situation. Utilizing this classification, we developed a time-series representation called the VUC Graph. This graph plots time on the x-axis against the VUC rating on the y-axis, facilitating a clear and comprehensive visualization of the various stages of volcanic unrest, including the onset, peak, and resolution phases, across different eruptions. This methodological advancement enables a more nuanced understanding of volcanic phenomena, allowing for a detailed analysis of their progression over time.
Our in-depth analysis of the Eruption Sequence Database (ESDB), utilizing the Volcanic Unrest Classification (VUC), has identified three fundamental patterns in large volcanic eruptions: Waning, Multipeak, and Escalating Types.
The Waning Type is the most prevalent among large-scale volcanic eruptions, exemplified by events such as the 1912 (Taisho) eruption of Sakurajima and the 2011 eruption of Puyehue Cordon-Caulle. These eruptions commence with an intensity of VEI 4-5 and gradually subside over months, typically transitioning from explosive Plinian eruptions to more subdued lava effusions. This pattern is frequently observed in volcanoes with a history of regular eruptive activity.
In contrast, the Multipeak Type is distinguished by its episodic nature and the absence of a singular climactic phase. Eruptions of this category, including those like the Augustine 1976 or Usu 1977 events, often involve effusive activity without reaching a definitive peak.
Although less common, the Escalating Type accounts for the most catastrophic eruptions, such as the 1883 Krakatau eruption, the 1991 Pinatubo eruption, and the 2022 Hunga-Tonga Hunga-Ha’apai eruption. These events begin with moderate activity and escalate rapidly, culminating in the partial or complete destruction of the volcanic structure. The critical period from the initial eruption to the climax typically spans months, suggesting that the potential for significant damage could be substantially reduced with accurate prediction.
Eruption Sequence Database: https://gbank.gsj.jp/volcano/esdb/
To decipher the complex dynamics of volcanic activity, we have pioneered a structured methodology known as the Volcanic Unrest Classification (VUC). This new approach assigns a numerical value, ranging from 0 to 7, to each event and observation, correlating directly to the severity of the situation. Utilizing this classification, we developed a time-series representation called the VUC Graph. This graph plots time on the x-axis against the VUC rating on the y-axis, facilitating a clear and comprehensive visualization of the various stages of volcanic unrest, including the onset, peak, and resolution phases, across different eruptions. This methodological advancement enables a more nuanced understanding of volcanic phenomena, allowing for a detailed analysis of their progression over time.
Our in-depth analysis of the Eruption Sequence Database (ESDB), utilizing the Volcanic Unrest Classification (VUC), has identified three fundamental patterns in large volcanic eruptions: Waning, Multipeak, and Escalating Types.
The Waning Type is the most prevalent among large-scale volcanic eruptions, exemplified by events such as the 1912 (Taisho) eruption of Sakurajima and the 2011 eruption of Puyehue Cordon-Caulle. These eruptions commence with an intensity of VEI 4-5 and gradually subside over months, typically transitioning from explosive Plinian eruptions to more subdued lava effusions. This pattern is frequently observed in volcanoes with a history of regular eruptive activity.
In contrast, the Multipeak Type is distinguished by its episodic nature and the absence of a singular climactic phase. Eruptions of this category, including those like the Augustine 1976 or Usu 1977 events, often involve effusive activity without reaching a definitive peak.
Although less common, the Escalating Type accounts for the most catastrophic eruptions, such as the 1883 Krakatau eruption, the 1991 Pinatubo eruption, and the 2022 Hunga-Tonga Hunga-Ha’apai eruption. These events begin with moderate activity and escalate rapidly, culminating in the partial or complete destruction of the volcanic structure. The critical period from the initial eruption to the climax typically spans months, suggesting that the potential for significant damage could be substantially reduced with accurate prediction.
Eruption Sequence Database: https://gbank.gsj.jp/volcano/esdb/