HR: 09:45h
AN: H31G-06    [Abstracts]
TI: Comparative Application of Dimensionless Bankfull Hydraulic Relations for Earth and Titan
AU: * Parker, G
EM: parkerg@uiuc.edu
AF: Dept. of Civil & Env. Eng. and Dept. of Geology, University of Illinois, Urbana, IL 61801 United States
AB: Recent evidence from the Huygens Probe of the Cassini Mission suggests that Titan, a satellite of Saturn, has rivers of flowing liquid methane which transport disaggregated crustal sediment in the form of ice. Surface images from the Huygens Probe show gravel-sized ice clasts that appear to be well-rounded by fluvial processes. If river morphodynamics on Earth is truly understood at a physical level, then relations that provide reasonable results on Earth ought to provide similarly reasonable results on Titan. These basic relations should be expressed in terms of dimensionless variabes. At least three dimensioned parameters that would be used to form the relevant dimensionless variables can be expected to vary notably between Earth and Titan. These are a) the acceleration of gravity, the kinematic viscosity of the flowing fluid and the submerged specific gravity of the sediment. Dimensionless relations for the threshold of motion, the threshold of significant suspension and bankfull hydraulic geometry that are known to work on Earth are used to predict features of rivers on Titan. Wildcards that make the predictions tentative include the formation of hydrocarbons on Titan that might add a kind of cohesivity not encountered on Earth and a freeze-thaw process of methane that might not be analogous to freeze-thaw processes in high-latitude rivers on Earth.
DE: 1815 Erosion
DE: 1825 Geomorphology: fluvial (1625)
DE: 1860 Streamflow
DE: 5415 Erosion and weathering
SC: Hydrology [H]
MN: Fall Meeting 2005