sgr ms thesis - University of Maine

achieve supersolidus temperatures. For example, volcanic tuff, quartzite, or calcsilicate
layers would not melt with the pelitic layers, leaving a preference to
preserve the clasts produced from the higher melting temperature layers. This
means that not all clasts would follow the same trend of melting, and could
explain why not all Bar Harbor Formation clasts completely melted in Type 3
Shatter Zone.
For the 900°C intrusion model, the clasts and matrix reach equilibrium at a
temperature well above Cadillac Mountain Granite feldspar crystallization
temperatures (Wiebe et al., 1997a), but the 800°C intrusion model is well below
the 825°C feldspar crystallization of the Cadillac mountain Granite (Wiebe et al.,
1997). Although the temperature remains above the Bar Harbor Formation
solidus for a relatively long time, feldspar crystallization would significantly
increase viscosity (e.g. Baker, 1996; Bea, 2010). If magma partially solidifies
around a clast, there is a reduced chance for disaggregation (e.g. Beard and
Ragland, 2005). For the 900°C intrusion model, the equilibrium temperature is
too high for a viscosity increase, but for the 800°C intrusion model, magma
crystallization may have been able to protect clasts from disaggregation with an
envelope of more viscous material.
The initial temperature and volume fraction of wall rock and magma
determine the equilibrium temperature. As seen in Figure 7.4, a lower magma
matrix percent by volume would cause less clast melting. Several initial intrusion
and clast temperatures are used to replicate potential magma temperatures and
wall rock temperatures with distance from the reservoir. Type 1 and 2 Shatter
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