PDF(Pubmed)
Abstract：
After 43 years of dormancy, Taal Volcano violently erupted in January 2020 forming a towering eruption plume. The fall deposits covered an area of 8605 km2, which includes Metro Manila of the National Capital Region of the Philippines. The tephra fall caused damage to crops, traffic congestion, roof collapse, and changes in air quality in the affected areas. In a tropical region where heavy rains are frequent, immediate collection of data is crucial in order to preserve the tephra fall deposit record, which is readily washed away by surface water runoff and prevailing winds. Crowdsourcing, field surveys, and laboratory analysis of the tephra fall deposits were conducted to document and characterize the tephra fall deposits of the 2020 Taal Volcano eruption and their impacts. Results show that the tephra fall deposit thins downwind exponentially with a thickness half distance of about 1.40 km and 9.49 km for the proximal and distal exponential segments, respectively. The total calculated volume of erupted fallout deposit is 0.057 km3, 0.042 km3, or 0.090 km3 using the exponential, power-law, and Weibull models, respectively, and all translate to a VEI of 3. However, using a probabilistic approach (Weibull method) with 90% confidence interval, the volume estimate is as high as 0.097 km3. With the addition of the base surge deposits amounting to 0.019 km3, the volume translates to a VEI of 4, consistent with the classification for the observed height and umbrella radius of the 2020 main eruption plume. VEI 4 is also consistent with the calculated median eruption plume height of 17.8 km and sub-plinian classification based on combined analysis of isopleth and isopach data. Phreatomagmatic activity originated from a vent located in Taal Volcano\'s Main Crater Lake (MCL), which contained 42 million m3 of water. This eruptive style is further supported by the characteristics of the ash grain components of the distal 12 January 2020 tephra fall deposits, consisting dominantly of andesitic vitric fragments (83-90%). Other components of the fall deposits are lithic (7-11%) and crystal (less than 6%) grains. Further textural and geochemical analysis of these tephra fall deposits contributes to better understand the volcanic processes that occurred at Taal Volcano, one of the 16 Decade Volcanoes identified by the International Association of Volcanology and Chemistry of the Earth\'s Interior (IAVCEI) because of its destructive nature and proximity to densely populated areas. The crowdsourcing initiative provided a significant portion of the data used for this study while at the same time educating and empowering the community to build resilience.
BACKGROUND: The online version contains supplementary material available at 10.1007/s00445-022-01534-y.
BACKGROUND: The online version contains supplementary material available at 10.1007/s00445-022-01534-y.
摘要：
经过43年的休眠,塔尔火山于2020年1月猛烈喷发，形成了高耸的喷发羽流。秋季矿床占地8605平方公里，其中包括菲律宾国家首都地区的马尼拉大都会。特非拉瀑布对庄稼造成损害,交通拥堵,屋顶坍塌,以及受影响地区的空气质量变化。在暴雨频发的热带地区，立即收集数据对于保存泰夫拉秋季存款记录至关重要，很容易被地表水径流和盛行的风冲走。众包,实地调查，并对特非拉瀑布矿床进行了实验室分析，以记录和描述2020年塔尔火山喷发的特非拉瀑布矿床及其影响。结果表明，tephra瀑布沉积物呈指数下降趋势，近端和远端指数段的厚度半距离约为1.40km和9.49km，分别。根据指数计算，喷发沉降沉积物的总体积为0.057km3、0.042km3或0.090km3，幂律,和Weibull模型，分别,和所有翻译为3的VEI。然而,使用90%置信区间的概率方法(威布尔法)，体积估计值高达0.097km3。基础涌流沉积物的添加量为0.019km3，体积转化为4的VEI，与2020年主要喷发羽流的观测高度和伞形半径的分类一致。VEI4也与17.8km的中值喷发羽流高度和基于等值线和等值线数据的综合分析的亚叠系分类一致。火山活动起源于位于塔尔火山主火山口湖（MCL）的喷口，其中包含4200万立方米的水。2020年1月12日特非拉秋季沉积物远端灰粒成分的特征进一步支持了这种喷发风格，主要由安山体玻璃体碎片（83-90％）组成。秋季沉积物的其他成分是石质（7-11％）和晶体（小于6％）晶粒。对这些特弗拉瀑布矿床进行进一步的结构和地球化学分析有助于更好地了解塔尔火山发生的火山过程，国际火山学和地球内部化学协会（IAVCEI）确定的16个十年火山之一，因为它具有破坏性和靠近人口稠密地区。众包倡议提供了用于本研究的很大一部分数据，同时教育和授权社区建立弹性。
背景：在线版本包含补充材料，可在10.1007/s00445-022-01534-y获得。
背景：在线版本包含补充材料，可在10.1007/s00445-022-01534-y获得。
