The Smithsonian/USGS Weekly Volcanic Activity Report provides information about global volcanism on a weekly basis. Latest Merapi report has been published on 27 Jan 2021 07:39.
BPPTKG reported that the ?2021 lava dome? continued to grow just below Merapi?s SW rim during 15-21 January, producing a total of 282 incandescent lava avalanches that traveled as far as 1 km down the Krasak and Boyong river drainages on the SW flank. Pyroclastic flows were recorded 19 times and descended the SW flanks as far as 1.8 km. A comparison of photos taken on 14 and 21 January showed that the morphological changes in the summit area were attributed to the emergence of new lava domes. The 2021 dome volume was an estimated 104,000 cubic meters on 21 January, with a growth rate of about 8,600 cubic meters per day. Deformation continued, though at a lower rate; Electronic Distance Measurement (EDM) data showed a distance shortening between points in the NW at a rate of 0.8 cm per day. Seismic activity was lower than the previous week. According to news articles ashfall was reported in several villages in the Musuk, Tamansari, and Kemalang districts on 19 January. The Alert Level remained at 3 (on a scale of 1-4), and the public were warned to stay 5 km away from the summit. Sources: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG),Detik News,Detik News
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