Viscous fingering during replenishment of felsic magma chambers by continuous inputs of mafic magmas: Field evidence and fluid-mechanics experiments

Abstract

Research Article| January 01, 2005 Viscous fingering during replenishment of felsic magma chambers by continuous inputs of mafic magmas: Field evidence and fluid-mechanics experiments D. Perugini; D. Perugini 1Department of Earth Science, University of Perugia, Piazza Università, 06100, Perugia, Italy Search for other works by this author on: GSW Google Scholar G. Poli G. Poli 1Department of Earth Science, University of Perugia, Piazza Università, 06100, Perugia, Italy Search for other works by this author on: GSW Google Scholar Geology (2005) 33 (1): 5–8. https://doi.org/10.1130/G21075.1 Article history received: 29 Jul 2004 rev-recd: 01 Oct 2004 accepted: 01 Oct 2004 first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation D. Perugini, G. Poli; Viscous fingering during replenishment of felsic magma chambers by continuous inputs of mafic magmas: Field evidence and fluid-mechanics experiments. Geology 2005;; 33 (1): 5–8. doi: https://doi.org/10.1130/G21075.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Vegetation Island outcrops (Terra Nova Intrusive Complex, Antarctica) offer a unique example of the replenishment of a felsic magma chamber fossilized at the initial stages of intrusion of a mafic magma. The morphology of interfaces between the mafic and the felsic magma ranges from rounded to finger-like, and their quantification by means of fractal dimension indicates a wide variability of morphological complexity. Fluid-mechanics experiments of viscous fingering have been performed by injecting water + glycerin solutions with different viscosity ratios into pure glycerin using the Hele-Shaw cell. The fact that interface morphologies between the injected and the host fluid are identical to those observed on outcrops indicates that the latter shows the development of viscous fingering processes during the initial stages of intrusion of the mafic magma into the felsic magma chamber. The fractal dimension of the simulated structures was measured, and a very good exponential empirical relationship between the logarithm of viscosity ratio and fractal dimension has been derived. The empirical relationship is used to estimate viscosity ratios of natural structures by using measured values of fractal dimension. Results indicate that in the same magmatic system, a wide range of viscosity ratio existed between the two magmas. These results are used to reconstruct the mechanism of replenishment of the felsic magma chamber as characterized by continuous heating of the resident felsic magma by continuous inputs of the mafic magma. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.