Manville, V.R.; Stevens, N.F.; Heron, D.W. 2003 Numerical simulation of debris avalanche hazards at Ruapehu : application of the USGS-LAHARZ GIS-program . Lower Hutt: Institute of Geological & Nuclear Sciences. Institute of Geological & Nuclear Sciences science report 2002/16 35 p.
Abstract: A growing trend in the field of volcanic hazard assessment is the use of computer models to predict potential areas of devastation by numerically simulating a variety of volcanic flow types. These can be compared with historic and geologic evidence of past events for model calibration, or used to construct hazard zone maps for mitigation and planning purposes. The LAHARZ model, developed at the United States Geological Survey Cascades Volcano Observatory, is designed to simulate the run-out of debris avalanches, huge landslides generate by the catastrophic collapse of volcanic edifices. Simulation of lahars and debris avalanches with volumes spanning 3 orders of magnitude at Ruapehu demonstrate some of the advantages and disadvantages of the programme. LAHARZ fails to model small lahars of the scale typically associated with historic volcanic eruptions accurately, but is more successful at simulating events larger than ~1 x 107 m3, which would be associated with gravitational collapse of, for example, the southeastern crater rim and Pyramid peak. Although limited by the inability to model velocity and hence run-up, LAHARZ offers a relatively rapid and reproducible method of assessing areas at risk of burial by debris avalanche deposits. (auth)