Journal
GEOLOGY
Volume 33, Issue 10, Pages 837-840Publisher
GEOLOGICAL SOC AMER, INC
DOI: 10.1130/G21675.1
Keywords
diffusion; olivine; assimilation; magma; time scales
Categories
Ask authors/readers for more resources
Open-system processes have a large capacity to modify magma compositions during differentiation. Obtaining the rates of such processes is essential to understanding and constraining the evolution of magmatic systems. Here we quantify the time scales for magmatic assimilation of hydrous malic to ultramafic cumulates by ascending basalts using the zoning patterns of ollivine xenocrysts. Robust diffusion modeling results have been obtained by treating multiple compositional profiles for multiple elements (Fe-Mg, Ni, Mn, Ca) on multiple crystals from multiple flows. We find that the time between assimilation and eruption ranges from a few months to similar to 25 yr, although 80% of the results are < 10 yr. These ranges are shorter than either magma transport times from the mantle to the surface or typical repose periods of arc volcanoes. Thus, modification of the geochemical and mineralogical features of basalts by assimilation of plutonic rocks is a fast and probably unavoidable magmatic process.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available