A dramatic improvement of the earthquake location model surprisingly show that, from 2014 to 2017, one major group of events (>1000) persistently clustered within a ~500 m diameter vertical conduit with a ~2 km height (Figure below). The seismic zone is probably triggered by the significantly volcanic gases and fluids ascending from the deep magma reservoir. Combined with a variety of results from literature, the seismicity conduit near the strong fumarole is the evidence for an active volcano and also identifies a likely pathway for ascending magma if the TVG erupts again in the future. But possibility of developing different magma pathways at other clustered seismic zones such as beneath Mt. Chihsin may not be totally excluded. The detailed results were published at Scientific Reports (Pu et al., 2020).
Pu, H.C., C.H. Lin*, Y.C. Lai, M.H. Shih, Y.H. Li, P.C. Lee, G.T. Hong, Y.W. Chang and C.H. Lo (2020), Active volcanism revealed from a clustering seismicity conduit beneath the long-resting Tatun volcano group in northern Taiwan, Scientific Reports, Vol. 10, 6153. https://doi.org/10.1038/s41598-020-63270-7