Geology Reference
In-Depth Information
Plate 4.1
The explosive volcanic vent that opened on 26 September 2005 after two days of nearly continuous seismic
activity. (a) The 500-m-long, 60-m-wide vent looking north. To the right lies a 200-m-wide, 4-km-long zone of open
fissures and normal faults that may mark the subsurface location of the dyke.
Photograph by Elizabeth Baker,
Royal Holloway, University of London
. (b) View to the south from the north end of the vent. Notice the tunnel at the
southern end. Notice the layers of ash that built up over a periods of days around the vent. The rhyolitic rocks in the
foreground were blown out of the vent. (
Photograph by Julie Rowland, University of Auckland
)
