Abstract
Changbaishan volcano (China/North Korea; last eruption in 1903 AD) was responsible for a Volcanic Explosivity Index (VEI) 7 eruption in 946 AD. Approximately 186,000 people live around Changbaishan and 2,000,000 tourists/year visit the volcano. An unrest occurred between 2002 and 2006. Despite the relevant hazard, the eruptive history is poorly known, a condition common to many volcanoes worldwide. Here, we investigate the extension of the areas potentially affected by pyroclastic density currents (PDCs) in case of future eruptions following a scenario-based approach. We perform energy cone runs referred to four scenarios from columns of height 3, 10, 20 and 30 km at different vents. By using global datasets on PDCs, we produce spatial probability maps of PDCs invasion. Empirical laws between covered areas, PDC travelled distances, and heights of collapse are provided. In scenarios 3 and 4, PDCs expand at distances up to 42 km and 85 km, respectively. In scenarios 1 and 2, PDCs invade the touristic area and few main roads. Severe effects emerge from scenarios 3 and 4 with the interruption of the China–North Korea land and aerial connections and PDC. Our approach may serve as guide for the rapid evaluation of the PDC-related hazard at poorly known volcanoes.
Highlights
Pyroclastic density currents (PDCs) may cover large distances in short times [1,2,3,4,5]
PDCsform by different mechanisms including the collapse of eruptive columns or domes [6,7], blasts associated to the depressurization of the volcano flanks [8], and syn-eruptive gravitational collapse of hot pyroclasts accumulated over steep slopes [9]
The evaluation of the hazard related to ash dispersion and PDC is of primary importance because about 135,000 people of China and 31,000 of North Korea live within 50 km from the Changbaishan caldera, and each year, 2,000,000 tourists visit the Changbaishan volcano National Reserve, a part of the UNESCO Man and Biosphere program [55] [56]
Summary
Pyroclastic density currents (PDCs) may cover large distances in short times (few minutes to hours) [1,2,3,4,5]. In a review of these different models, [24] show that LAHARZ and EC can be used as first-approximation of flow runouts using the parameters listed in the FlowDat database [25] and other general or local databases [26,27,28] These models may provide simple hazard maps when run with a variety of input volumes. TITAN2D and VolcFlow are efficient in producing scenario-based or probabilistic hazard maps, but they need to run many times with varying input parameters. They are efficient to simulate single pulse, smaller-volume flows, whereas they are less sensitive in reproducing larger-volume flows.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
