Activity Bulletin Wednesday, November 11, 2015 at 10:00 am (local time)
In recent days, the OVPF networks recorded geophysical and geochemical signs of a new pressurizing of the volcano.
As regards the seismicity, 130 summital earthquakes have been recorded accompanied by 62 deep earthquakes. In reality, the number of deep earthquakes is much higher because many of them are too small to be determined by conventional methods.
From the perspective of deformations, we observed between each effusive phase a rise in inflation whether the summit area (DSRG–SNEG), the area of the cone summit base (FREG–ENOG) or the distal region (gitg–PRAG). Since October 31, this trend is very clearly established and we see a pressurization of the massif.
The change in gas flow also reflects the deep pressurization.
That day an aerial survey with the assistance of SAG was made. It shows that the Piton Kala and Pele tends to collapse on itself. Moreover, many white fumaroles demonstrate the persistent high temperature of the lava field.
Since the end of last effusive phase of the Piton de la Fournaise (October 31 4:17 p.m.), the residual signal which continued to be recorded by the Observatory’s instruments has gradually diminished and ending to virtually disappear, which was not observed in the two previous inter-effusive phases. Now, only rare few of gases are identified in the seismic signal and a more traditional activity his reinstalled:
The summit and deep seismic activity has resumed.
Inflation detected at the top has now resumed.
We also record an increase in the flow of deep origin gas.
Recall, at present, no more lava flow and no lava fountain activity or strombolian explosion is visible at the vent newly appointed Piton Kalla and Pele.
November 12, 2015. Piton de la Fournaise, La Réunion :
Source : OVPF
Photo : Geoffrey Petit.