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Scaling laws of the size distribution of monogenetic volcanoes within the Michoacan-Guanajuato Volcanic Field (Mexico). Michoacan-Guanajuato Volcanic Field. 1040 monogenetic volcanoes Mainly basaltic cinder cones Used size of m-volcano defined by basal diameter 1 or very few magma pulses
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Scaling laws of the size distribution of monogenetic volcanoes within the Michoacan-Guanajuato Volcanic Field (Mexico)
Michoacan-Guanajuato Volcanic Field • 1040 monogenetic volcanoes • Mainly basaltic cinder cones • Used size of m-volcano defined by basal diameter • 1 or very few magma pulses • Rivera and Cocos plate subduction • Transmexican Volcanic Belt (TMVB) • Largest intra continental volcanic arc • Estimated morphometric parameters (height, diameter [base and crater], and volume) • Gathered information from topo maps and measurements in the field
Conclusions • Similar power-law to Gutenberg-Richter • Respect to size-distribution • Log10[N(size>Wco)] = a – b log10[Wco] • b: rate of occurrence between small/large volcanoes • N: # volcanoes with diameter greater than Wco (1.33km) • a = 2.98, b = 5.02, Wco > 1.33 km • Self-organized criticality phenomenon • Monogenetic fields distributed as fractal in size • Formula can be applied to future volcanoes • Assess hazard • B-paramater directly related to monogenetic volcanic activity • Size distribution does not occur randomly
Gutenberg-Richter Law • The number of earthquakes of magnitude M is proportional to 10-bM • Look at the graph (all the earthquakes in 1995) • red line gives the Gutenberg-Richter prediction with b = 1. The value of b seems to vary from area to area, but worldwide it seems to be around b=1.