On the island of Lombok, the earthquake of M 6.4 of 28 July / 22h47 UTC was followed by 280 aftershocks (number at 30.07 / 10 local) of magnitude between 5.7 and 2.1.
The epicenter is located in a northern area composed of alluvial rocks and volcanic sediments, which has facilitated many landslides; Of the 820 foreign hikers, most of them Thais, on the Rinjani volcano at the time of the earthquake, more than 500 are stranded, and should be evacuated by helicopter on 30 July.
Sources: PVMBG, BNPB and media
In the Moluccas, a Volcanodiscpovery team, on the spot, observed numerous explosions and a new lava flow on the western flanks of Gunung Ibu.
Seismicity has been high for a few days, and the PVMBG informs for July 28, 113 earthquakes of eruption, 129 emission earthquakes, 45 avalanche earthquakes, and 4 distant tectonic earthquakes. On July 29, these are 125 earthquakes, 136 earthquakes, 32 avalanche events, and 4 distant earthquakes occurred.
Sources: Volcanodiscovery and PVMBG
An image of the Suomi NPP / OMPS satellite of 29.07.2018 summarizes the sulfur dioxide emanations of volcanic origin on the Pacific.
There is an important SO2 plume associated with the July 26-27 eruptions on Ambae, emissions from the East Rift Zone of Kilauea and that of Sierra Negra, still erupting, but waning, in the Galapagos Archipelago.
Source: satellite image via Simon Carn
SO2 emissions on the Pacific: bottom left, plume of Ambae following eruptions of 26 and 27.07 - in the center-up, emissions of the eruption underway at Kilauea - right, those of Sierra Negra, waning, in Galapagos - Suomi NPP / OMPS satellite image from 29.07.2018 via Simon Carn
Kilauea East Rift Zone - Sulfur dioxide emissions remain important on fissure 8 - Photo Dand Dupont via Hawaii Tracker
In Kamchatka, the Karymsky, in orange aviation alert, presents, since July 14, emissions of ashes.
On July 29, the KVERT reports emissions of ash and steam at 1,500-2,000 meters asl., drifting 33 km to the southeast.
These ash emissions continue on July 30, and disperse to the northeast over 92 km.
On July 29, 2018, a short window in the cloud cover shows the summit of Villarica with incandescence; it is stronger than that observed in recent days, and shows two active orifices.
Since the 90s, scientists have begun to take an interest in the dynamics of a lava lake at the bottom of the crater, which stands out during the clear nights by an incandescence at the top. P.O.V.I. has begun to document the various manifestations of this phenomenon in a systematic way since 1998.
The fire of the volcano occupied a preponderant place in the religion of the peoples of origin, long before the arrival of the first conquerors in the region.
The first description of a lava lake dates from about 1560, and is due to Rosales who describes: "... he keeps the snow all year round on his gray head, even at the worst of summer, and emits plumes of fire by his crown, making the two opposites compete, the fire and the snow, without being able to favor one or the other, and preserving the fire of the lord within the hill ".
Villarica has had this lava lake for over 450 years.
Source: Werner Keller / POVI - www. Povi.cl