Computer Simulations of Magma Chamber Evolution : Testing an Alternative Model for the Development of Layered Mafic Intrusions and the Origin of Granite
File(s)
Date
2010-04Author
Spencer, Christopher B.
Advisor(s)
Ihinger, Phillip D.
Metadata
Show full item recordAbstract
The association of granite and basalt is observed in every large basaltic magma chamber. Large basaltic rock bodies (termed LMIs, for Layered Mafic Intrusions) provide unique insights into the evolution of the material that makes up over 75% of the Earth?s crust. Yet, the details of LMI evolution remain obscure and controversial. For example, many studies of
the well-exposed Skaergaard Intrusion in Greenland document a relatively simple, closed-system evolution in which a single vat of magma
progressively crystallized from the outside in. However, the compositions of individual rock layers do not represent realistic magma compositions, and the average composition of the entire intrusion is significantly more
mafic (i.e., poor in SiO2) than the initial basaltic melt preserved on the chilled margins of the intrusion. Here, we test the viability of an
alternative model that can explain this paradox.
Subject
Granite--Analysis
Granite--Inclusions--Computer simulation
Intrusions (Geology)--Computer simulation
Magmatism--Computer simulation
Skaergaard Intrusion (Greenland)
Posters
Permanent Link
http://digital.library.wisc.edu/1793/46353Description
Color poster with text, images, and graphs.