Looking into the mouth
of an effusive vent near the hornitos at the southeastern base of the
SE Cone, 10 June 1999
Sketch map of the
Valle del Bove and area of the lava flow-field emplaced since 4 February
A brief visit was made on the late afternoon of 10 June to the active effusive vents near the SE Cone by Boris Behncke and Francesca Ghisetti of the Istituto di Geologia e Geofisica of Catania University (IGGUC). Since Behncke's previous visit on 4 June, the output of lava from the 4 February eruptive fissure has increased notably while only one ephemeral vent continues to emit lava on the western Valle del Bove slope. The active vents on the 4 February fissure are located only about 10-20 m below the hornitos at the upper end of the fissure, and effusive activity has shifted tens of meters upslope during the past 4 weeks.
While there was one vigorous effusive vent located right on the fissure, lava also issued from numerous places within and on the margins of recent flows which have accumulated on the southwestern side of the lava field emplaced since 4 February. A well-fed flow moved down the northern side of that lava field and appears to have spilled over the rim of Valle del Bove to the north of the previously emplaced lavas. Dust clouds generated by rockfalls and bluish fumes indicated lava moving in that area which was not accessible. The ephemeral vent on the western Valle del Bove slope, in the area of the tumulus collapsed on 19 May emitted a sluggish flow that advanced only a few meters downslope, and there was no effusive activity elsewhere in that area. This indicates that supply to its feeder tube is much reduced, probably causing the increased surface lava emission below the hornitos.
Page set up on 27 May 1997, last modified on 18 June 1999