sgr ms thesis - University of Maine

necessary to account for precise changes in temperature. The model cannot
address the non-linear effect of magma crystallization rates, so latent heat is
evenly dispersed during the entire duration dT. I assume that the Bar Harbor
Formation was previously metamorphosed to avoid including endothermic
metamorphic reactions that counterbalance latent heat (Kerrick, 1991). In
addition, the short time frames associated with granite crystallization would
probably limit the progress of potential metamorphic reactions.
7.2.2. Methods for Plotting Data
Temperature contouring is a useful method for evaluating the degree and
time frame of partial melting in clasts. I took a transient thermal solution and
plotted the continuously migrating solidus of the Bar Harbor Formation clasts in
order to determine the rate of clast partial melt (the Stefan problem, Turcotte and
Schubert, 1982). Two solidus migration plots are produced. The spherical twodimensional
clast model was used to find the general trend of solidus migration
into a clast with time. COMSOL results were used to collect transient thermal and
spatial data along a transect through the clast center. The second plot used data
from outcrop geometry to plot percent partial melt volume with respect to time.
The plot was produced from model images of clast area above the solidus
temperature for 30 chosen time steps. Clast area remaining below the solidus
temperature was calculated in NIH ImageJ, and percent partial melt by area
( ) was
calculated for each time step.
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