Volcanos

Roundup of Global Volcanic Activity - New Activity for the week 11 January - 17 January 2023

Dieng Volcanic Complex - Central Java : PVMBG reported increasing activity at Dieng Volcanic Complex in a press release posted on 14 January. The number of deep volcanic earthquakes and local tectonic earthquakes had been increasing starting on 9 January. Carbon dioxide gas concentrations at Timbang Crater also intensified, averaging 0.09-0.11 percent during 1-13 January. Primary hazards at Dieng included phreatic eruptions at Sileri Crater and flows of carbon dioxide gas that can impact residents and tourists. At 2116 on 15 January carbon dioxide emissions significantly increased. The carbon dioxide gas concentration at 0027 on 16 January was 5,600 parts per million (ppm), rising to 7,300 ppm by 0130. The mobile instrument measuring the gas was located 170 m from the midpoint of Timbang Crater. At 0540 the gas concentration was as high as 10,000 ppm, measured from 130 m away from the crater’s midpoint. In a second press release, PVMBG warned the public to stay 500 m away from the SE, S, and SW sectors of Timbang Crater.

Ijen - Eastern Java : PVMBG reported that unrest continued at Ijen during 10-17 January. There were 2-30 daily earthquakes indicating emissions and 2-19 daily shallow volcanic earthquakes. One tornillo earthquake was recorded on 10 January. Diffuse white gas plumes were visible rising as high as 400 m above the summit during 10-14 January.

Kilauea - Hawaiian Islands (USA) : HVO reported that lava continued to erupt from vents on the central E portion of Kilauea’s Halema’uma’u Crater floor during 10-17 January. Activity was concentrated in a large lava lake, covering about 12 hectares in the E half of the crater on 10 January. One dominant lava fountain, 6-7 m high, was active within this area. Lava flows built up the margins of the lake, causing the lake to be perched; small overflows along the margins were visible during 13-16 January. A smaller area of lava was active within the basin in the W half of the crater that had been the focus of activity during 2021-2022.

Marapi - Central Sumatra : PVMBG reported that the explosive eruption at Marapi continued during 10-17 January with daily dense ash plumes rising above the crater rim and drifting in various directions. White-and-gray ash plumes at 0900 and 0912 on 10 January rose 200-300 m and drifted NE and SE. Gray ash plumes rose 400-800 m at 0825, 0941, and 1133 on 11 January and drifted N, NE, E, and SE. Multiple gray ash plumes visible on 12 January (0640, 0936, 1042, 1058, 1217, 1824) rose as high as 1 km and drifted NE, E, and SE. White-and-gray ash plumes rose 200-600 m and drifted NE, SE, and SW during 13-15 January; rainy weather conditions prevented visual observations on 16 January.

Semisopochnoi - Aleutian Islands (USA) : AVO reported that eruptive activity at Semisopochnoi’s Mount Young was ongoing during 10-17 January. Seismicity was elevated with small local earthquakes and weak tremor. Minor steam emissions were visible in webcam images during 11 and 16-17 January. Several small explosion signals were detected by local seismic and infrasound sensors during 16-17 January; no activity was identified in cloudy satellite views.