Equilibration during mantle melting: a fractal tree model.
نویسندگان
چکیده
منابع مشابه
Equilibration during mantle melting: a fractal tree model.
Many basalts from oceanic islands, ridges, and arcs show strong trace element evidence for melting at great depths, where garnet is a stable phase in mantle peridotites. If partial melts ascend to the surface by porous (intergranular) flow processes, the high-pressure garnet signature will be obliterated by diffusive reequilibration at shallower depths in the mantle. Spiegelman and Kenyon [Spie...
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Recent studies have shown that the extraction of water from the mantle due to partial melting beneath mid-ocean ridges may increase the viscosity of the residuum by 2–3 orders of magnitude. We examine this rheological effect on mantle flow and melting of a ridge-centered mantle plume using three-dimensional numerical models. Results indicate that the viscosity increase associated with dehydrati...
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Batch melting of ascending mantle can be approximated as an isentropic process, since on the time scale of melting heat flow into or out of source regions will typically be negligible and the process is slow enough to be close to reversible. Similarly, fractional fusion can be idealized as a series of incremental isentropic melting steps, although the entropy of the residue decreases in each st...
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Introduction: Whereas previous experimental studies [1,2,3] and interpretation of Apollo seismic experiments [4,5] are permissive for garnet in the deep lunar mantle, interpretations of Lu-Hf isotopic systematics [6] and trace element data [7] seem to require garnet in the source of selected mare basalts. Understanding the mineralogy of the deep lunar mantle is critical to our further interpret...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1993
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.90.24.11914