A large steam plume, generated by evaporating sea water at the entry of lava flows into the sea is seen on the satellite image, drifting north.
The island has apparently passed through an explosive Surtseyan phase very quickly, probably because the erupting basalt lava was poor in gas and because the output rate was high, so that the vent could be sealed from water access in short time. [less]

Due to further increased seismic activity, stronger degassing and steaming, the Indonesian Geological Survey has raised the alert level for Ijen volcano from 2 to 3 (out of 4). A phreatic eruption could occur any time, geologists believe. The lake has changed color to white.
The last eruption was in 1993 and had produced ash plumes rising about 1000 m. [less]

The last significant activity at Lokon was in mid July, when a violent phase of ash explosions forced the evacuation of 5,000 people from 3 villages. [less]

A warning for possible eruptions was issued and it is advised to stay out of a 4 km radius around the volcano and not to fly over it. [less]

A significant plume of sulfur dioxide and a thermal anomaly are visible on satellite images, indicating that there is still effusion of lava, probably accompanied by strombolian activity at the new vent. [less]

More sources are emerging, confirming that in fact an eruption seems to have taken place:
Aref Hamoud, a reader from Yemen confirms us the original report, that an eruption happened on 19 Dec on "Saba Island Coordinates: (Lat. 15° 5'13.38"N Long. 42° 9'10.12"E)", and that people in the area could feel a quake associated with it that day. [less]

We selected this photo as the "Photo of the Month" Dec 2011 and congratulate Christian with a 500 EUR travel voucher! [less]

Over millions of years, rainwater has seeped through the ash layers of ash and dissolved silica and other minerals from the volcanic layers. The wood of the trees was replaced by silicates.
Only about twenty years ago, large petrified forests were discovered by accident in the vicinity of the village of Sigri, where inhabitants wondered why some rocks looked like precious stones and wood at the same time. [less]

Volcanic tremor has decreased a lot, and there are almost no more bursts related to steam explosions at the underwater vent. Diffuse CO2 emissions (CO2 being interpreted as indication of fresh magma supply) has decreased, too. Earthquakes which are often related when new magma intrusions create new paths in the substrata, have almost stopped as well. The water discoloration south of La Restinga is still present and weak upwelling of muddy water is still being observed, but much less than previously, and with less intensity. [less]

An exclusion zone of 1 km around the crater has been established. Workers and tourists are currently not allowed to go inside the crater. [less]

The submarine volcano whose peak rises to just 18 m below sea level, is located on the tectonically active SW-NE fault system across Santorini which confines most volcanic vents of the Santorini volcanic complex in the past 500,000 years.
Kolumbus volcano last erupted in September 1650 following a year of frequent earthquakes. The eruption produced a large explosive pumice eruption, with ash fall recorded as far as Turkey, and built a temporary island. The main phase of the eruption triggered a devastating tsunami. Toxic gasses killed more than 25 people and hundreds of livestock on Santorini by suffocation (probably H2S). [less]

It shows that there the submarine eruption is going on strong with steam explosions at depth. [less]

The visible stain and "jacuzzi", i.e. rising bubbly and muddy water above the vent area has been more vigorous in the past days, although no reports are available about steaming blocks reaching the surface.
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- Tremors occuring continuously with amplitudes of maximal 0,5 - 2 mm ( recorded on the seismograph)
- Volcanic earthquake : 52 times [less]

Today marks the first day since the beginning of March that lava flows are accessible up close. Contact us today for an up close lava experience while these conditions last! [less]

There are reports of damage or fatalities. According to the news, some people from nearby villages have evacuated to safer locations, while a number remained at their homes.
No ash seems to be visible on satellite imaginary: the VAAC Darwin has not issued any advisories, suggesting that the eruption is small. On the other hand, ash is difficult to detect in tropical areas with heavy cloud cover. [less]

Explosions produced ash plumes rising 3-5 km above the crater and produced small pyroclastic flows of app. 500 m length on the western flank. Ejections of incandescent lava blocks to up to 1 km distance were observed. Ash fall is occurring in nearby villages, inclucing Palitahua, Runtún, Cusúa, Pillate and Juive. Strong explosion sounds are heard in Baños, Cusúa, Runtún and Pillate, where shock waves rattle doors and windows.
The lack of rain has (so-far) prevented the formation of dangerous mud flows (lahars). [less]

Seismic activity continues to decrease overall, suggesting that the eruption is slowly ending, to the relief of many inhabitants of the island (and to the disappointment of others... who would have loved to see a new island emerge).
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According to National Coordinator for Disaster Reduction (CONRED), explosions produce a plume drifting to the southwest and reaching about 20 km length. Small, but frequent rock avalanches are observed in the "Ash Canyon" on the steep southern side of the summit cone. [less]

The alignment (also known as the Kameni and Kolumbus lines) is a ca. 2 km wide zone parallel to a tectonic horst and graben structure of the crystalline basement of the area. Most of the known volcanic vents of Santorini during the past 2 million years were located on this alignment, more precisely either on its southern boundary (Kameni line) or on its northern boundary (Kolumbus line).
Lacking other data sources, the information visible on the location and number of earthquakes is too weak, other than to vaguely speculate that the current earthquake activity around Santorini could be a precursor to new activity from this volcano. Santorini's last eruption was in 1950. [less]