TY - JOUR
T1 - Flooding and flow path selection on alluvial fans and deltas
AU - Reitz, Meredith D.
AU - Jerolmack, Douglas J.
AU - Swenson, John B.
PY - 2010/3
Y1 - 2010/3
N2 - The surfaces of alluvial fans and river deltas (collectively fans) are often dissected by a small number of channels radiating from the fan apex. On long timescales, channels migrate via avulsion, the process of channel bed deposition and abandonment that often results in catastrophic flooding and loss of life on densely populated fans. We present results of an experimental fan that creates realistic channel patterns by avulsion. The avulsion cycle occurs with a period that is predictable from conservation of mass. Selection of a new flow path is inherently stochastic; however, once a network of 4-5 channels is established, flow oscillates among these channels indefinitely. We demonstrate that a directed random walk model with memory quantitatively reproduces these dynamics and limiting behavior, and is consistent with natural fans.
AB - The surfaces of alluvial fans and river deltas (collectively fans) are often dissected by a small number of channels radiating from the fan apex. On long timescales, channels migrate via avulsion, the process of channel bed deposition and abandonment that often results in catastrophic flooding and loss of life on densely populated fans. We present results of an experimental fan that creates realistic channel patterns by avulsion. The avulsion cycle occurs with a period that is predictable from conservation of mass. Selection of a new flow path is inherently stochastic; however, once a network of 4-5 channels is established, flow oscillates among these channels indefinitely. We demonstrate that a directed random walk model with memory quantitatively reproduces these dynamics and limiting behavior, and is consistent with natural fans.
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U2 - 10.1029/2009GL041985
DO - 10.1029/2009GL041985
M3 - Article
AN - SCOPUS:77949856354
SN - 0094-8276
VL - 37
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 6
M1 - L06401
ER -