Fluvial Recovery at Mount
Pinatubo
My dissertation investigated how a fluvial system responds
to extreme sediment loading and how the system recovers as sediment yields
decline. The project focused on Mount Pinatubo, which erupted in 1991, depositing 5-6 km3
of pyroclastic debris in basins draining the flanks of the volcano. Through time, sediment yields are declining,
essentially setting up a natural flume experiment that allows fluvial
geomorphologists to study an end-member case of sediment loading and the
processes by which rivers reestablish equilibrium conditions. Data collected from a series of 5 rivers on
the east side of Pinatubo from 1997 through 2003 show the processes by which
channel recovery occurs. My research
examined fluvial recovery at multiple spatial scales, from longitudinal
recovery of the valley to detailed studies of changes in bed texture and grain
mobility at a site, linking the basin-scale observations with changes in the
sediment transport regime.
I studied five basins on the east flank of Mount
Pinatubo. Most of my
efforts centered on the Sacobia River and the Pasig-Potrero River, both of
which had ~30% of the basin covered with pyroclastic debris as a result of the
1991 eruption. In October 1993, the Pasig-Potrero River
captured the upper Sacobia River drainage basin, doubling the basin area of the Pasig-Potrero River. This led to an increase in drainage area
without a corresponding increase in sediment load. The result is that the Pasig-Potrero appears
to be recovering at a faster rate than the Sacobia.
This website is currently being updated with recent
publications and presentations.
GSA
2002 poster
Project Bibliography
This research was supported through grants from the National Science
Foundation, the Geological Society of America, and the Dept. of Earth &
Space Sciences at the University
of Washington. My funding came primarily from a STAR graduate
fellowship through the EPA.