I am modeling the injection of hot magma sills into the Earth's crust at varying rates (and varying sill heights for each rate). For instance, for a total of 16 km of magma ... 1a-n. 40, 400m high sills emplaced at rate of 5e-3 ma-1, 5e-4 ma-1, 1e-2 ma-1, , 2e-2 ma-1, 3e-2 ma-1, and 4e-2 ma-1 1b-n. 160, 100m high sills emplaced at the same set of rates 1c-n. 320 sills, 50 m high at each of the rates and ... 1d-n. 640 sills (25 m high) at each rate. What you might expect is that at some rate, as sill size decreases, the hot zone will get larger (ostensibly because the magma retains more heat and cools more slowly when the time between sills is shorter). That is what I generally see. What is strange is that for a few sets I got a results suggesting a much larger hot zone would results from say, 320, 50m sills than for 640, 25m sills (this happens at an injection rate of 1e-2 ma-1) or in another set that ... a larger hot zone is created with 160 100m sills than for 320 50m sills or for 640 25m sills emplaced at the same overall rate (2e-2 ma-1). This is easier to understand when looking at the figures. You can see them here: https://www.dropbox.com/s/3atk0p47sfvjb5h/Screen Shot 2015-04-20 at 2.54.59 PM.png?dl=0 https://www.dropbox.com/s/v7r6t41swis1ksd/Screen Shot 2015-04-20 at 2.54.37 PM.png?dl=0 https://www.dropbox.com/s/lwwxps2jznptmcq/Screen Shot 2015-04-20 at 2.54.24 PM.png?dl=0 Does anyone have a way to explain why this occurs?