MOLASSES is a lava flow simulation tool designed to simulate the eruption and emplacement of lava flows, such as those that pave the lunar surface.
MOLASSES
Some background on the modeling of lava flows: PDF file (20MB)
Some background on on the statistical modeling of volcanic vent locations: PDF file (10MB)
MOLASSES stands for MOdular LAva Simulation Software for the Earth Sciences
The code relies on a cellular automata algorithm to estimate the area inundated by lava flows. Check out a simplified illustration of cellular automata for lava flows.
MOLASSES does not model the rate of lava emplacement or the dynamics of lava flows
A digital elevation model (DEM) of the volcanic region is pre-loaded on the server; lava flows are simulated using this DEM
Rheology is accounted for by specifying modal lava thickness. The thickness of lava flows, especially their margins, is a function of the lava flow yield strength. Yield strength is a more useful rheological parameter than viscosity, since the code does not account for dynamics.
MOLASSES is specifically designed to handle pooling of lava, for example in pre-existing craters
MOLASSES is modular, so it is relatively straightforward to modify the distribute algorthim for alternative emplacement mechanisms - such as to test development of flow levees, channels and rilles.
Inputs
MOLASSES takes the following inputs:
Volcanic vent location. Location can be specified exactly or using a spatial density model to randomly pick a vent location based on the distribution of mapped vents around the volcano system. The first time you run MOLASSES, specify location using spatial density to see the map area UTM coordinates.
Lava residual (modal) thickness (meters). Typical numbers range from 2 to 50 meters. Input the most common (modal) thickness of the lava flow. The code will distribute greater accumulations (thicknesses) of lava from cell to cell. The code can also pool lava in low lying areas and thicn the lava flow on steep slopes. The residual thickness should be consistent with the yield strength of the simulated lava flow.
Lava flow volume (cubic meters). Typical numbers range from 1e6 (1,000,000) to 1e10 cubic meters; 1e9 corresponds to one cubic kilometer. MOLASSES continues to execute until this total volume of lava is erupted on to the DEM.
Lava flow pulse volume (cubic meters). A fraction of the total lava flow volume, typically 1e4 to 1e6 cubic meters. This is the amount of lava erupted into the vent cell at each iteration. Relatively small pulse volumes tend to make the lava flow closely follow topography, large pulse volumes allow the lava flow to bury topography.
Outputs
MOLASSES outputs:
A map, showing the area inundated by the lava flow on a shaded relief DEM
vent location is shown by white circle
You can chose to save the png image of the map by right clicking on the map
You can download various files used to create the map, and numerical results
if the map is not created, you may have an incorrect vent location (off the map) or incorrect volumes (too small to see?)
Original application of the proto-version of MOLASSES:
Connor, L. J., Connor, C. B., Meliksetian, K., & Savov, I. (2012). Probabilistic approach to modeling lava flow inundation: a lava flow hazard assessment for a nuclear facility in Armenia. Journal of Applied Volcanology, 1(1), 3.
Comparison of MOLASSES output and an actual lava flow:
Kubanek, J., Richardson, J. A., Charbonnier, S. J., & Connor, L. J. (2015). Lava flow mapping and volume calculations for the 2012–2013 Tolbachik, Kamchatka, fissure eruption using bistatic TanDEM-X InSAR. Bulletin of Volcanology, 77(12), 106.
Benchmarking MOLASSES and similar codes:
Dietterich, H. R., Lev, E., Chen, J., Richardson, J. A., & Cashman, K. V. (2017). Benchmarking computational fluid dynamics models of lava flow simulation for hazard assessment, forecasting, and risk management. Journal of Applied Volcanology, 6(1), 9.
Development of MOLASSES was funded by a grant from the US National Science Foundation