"The ash column was observed to be white to gray, thick, and drifting east and southeast," reported Sigit Rian Alfian, an officer at the Mount Semeru Volcano Observation Post in Mount Sawur, Lumajang Regency, in his written report on Thursday.
Sigit noted that the 9:17 AM eruption registered on the seismogram with a maximum amplitude of 22 mm and lasted approximately 1 minute and 57 seconds. Over the preceding 24 hours, seismic data recorded 61 eruption tremors (10-22 mm amplitude, 51-154 second duration), 9 gust tremors (3-8 mm amplitude, 27-64 second duration), 1 harmonic tremor (8 mm amplitude, 134 second duration), and 3 volcanic tremors (4-25 mm amplitude, S-P 2-3 seconds, 15-22 second duration).
Comment: Also of note, significant damage to the region's orchards has been reported.