Figure 10: Volcanism is waning
in the SVF since about 0.75 Ma. This decrease in observed recurrence rate,
based on mean age determinations (heavy solid line with solid squares),
is captured by near-neighbor models using a 0.5 m.y. time window, rather
than all of the volcanoes formed prior to the time for which the calculation
is made. Near-neighbor models m = 7 (solid circles) and m =
8 (open circles) are shown. Using m = 7 near-neighbor vents and
a time window of 0.25 m.y. underestimates recurrence rate since 1.0 Ma
(open triangles).
