Collaborative Research: Quantifying the Emplacement of Channeled Flow Using Experimental, Analytical and Numerical Analyses
Tracy Gregg Principal Investigator
MetadataShow full item record
Gregg<br/>EAR-0001295<br/><br/>Although channeled lava flows are common throughout the solar system, relations between channel morphology, eruption and emplacement parameters, and lava properties are not well understood. Results from our previous study, combining analytical models with carefully controlled laboratory simulations raised many questions that could not be addressed with<br/>available data. Our current proposal addresses these limitations by collecting data from additional laboratory simulations, specifically to isolate the effects of underlying slope and slope breaks on channel development, the effects of rheology, and the effects of temperature-dependent viscosities on channel morphology. This will be accomplished by using PEG (a Newtonian fluid with a temperature-dependent viscosity), kaolin-charged PEG (a Bingham fluid with a temperature-dependent viscosity) and kaolin slurries (an isothermal Bingham fluid) to generate channeled flows on different underlying slopes (1degree-50 degrees) in the laboratory. Velocity distributions within channeled laboratory flows will be carefully measured using neutrally buoyant colored beads injected into the flow as tracers. Computational fluid dynamics (CFD) flow simulations developed by Dr. Sakimoto will be modified to treat the conditions found in laboratory flows. Preliminary CFD simulations will be run to understand the significance in laboratory flows of such effects as non-homogenous temperature distributions, heat loss from the PEG and tank<br/>bottom to the laboratory environment, and diffusion of PEG into the surrounding sucrose solution. Morphologic parameters from the simulated flows conducted by Dr. Gregg will be measured used to validate and refine CFD simulation results. The CFD simulations, in turn, will be used to fully characterize and understand the physical processes that dominate flow<br/>emplacement and cooling in the laboratory. These results will be tested against natural basaltic lava flows, such as the 1984 Mauna Loa, Hawaii eruption and smaller pahoehoe channels produced during the current eruption of Pu'u O'o at Kilauea volcano, Hawaii.