Oceanography > Issues > Archive > Volume 25, Issue 1

2012, Oceanography 25(1):78–88, http://dx.doi.org/10.5670/oceanog.2012.05

Geodynamic Models of Melt Generation and Extraction
at Mid-Ocean Ridges

Authors | Abstract | Full Article | Citation | References







Authors

Patricia M. Gregg | College of Earth, Oceanic, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA

Laura B. Hebert | Department of Geology, University of Maryland, College Park, MD, USA

Laurent G.J. Montési | Department of Geology, University of Maryland, College Park, MD, USA

Richard F. Katz | Department of Earth Sciences, University of Oxford, Oxford, UK

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Abstract

It is widely accepted that plate divergence at mid-ocean ridges drives mantle flow, mantle melting, and the formation of new oceanic crust. However, many of the details of this process remain obscure because of the inaccessibility of the mantle to direct observation. Thus, geodynamic models are needed to provide insight into the processes that control the formation of new crust and hydrothermal circulation at mid-ocean ridges. These models allow us to test governing parameters and investigate physical hypotheses and conceptual models derived from geological, geophysical, and geochemical observations. During the span of the Ridge 2000 Program, a new generation of models was developed to calculate the width of the melt region and the extent of melting beneath mid-ocean ridges, track the pathways along which melts may migrate, and predict melt and residual mantle compositions as the system evolves. Findings from these studies illustrate the importance of melt focusing for the efficient delivery of melt to the ridge axis, the complexities of migrating melt in the vicinity of ridge offsets, and the effect of mantle rheology in model calculations.

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Full Article

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Citation

Gregg, P.M., L.B. Hebert, L.G.J. Montési, and R.F. Katz. 2012. Geodynamic models of melt generation and extraction at mid-ocean ridges. Oceanography 25(1):78–88, http://dx.doi.org/10.5670/oceanog.2012.05.

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