The plumbotectonic model for Pb isotopic systematics among major terrestrial reservoirs—A case for bi-directional transport

doi:10.1016/0016-7037(88)90204-9

Geochimica et Cosmochimica Acta

Volume 52, Issue 6, June 1988, Pages 1327-1339

https://doi.org/10.1016/0016-7037(88)90204-9 Get rights and content

Abstract

Version IV of plumbotectonics expands and refines the original model of Doe and Zartman (1979) and Zartman and Doe (1981) for explaining Pb (Sr, and Nd) isotopic systematics among major terrestrial reservoirs. A case for bi-directional transport among reservoirs is based on the observed isotopic compositions for different tectonic settings, and finds a rationale in the kinetics of plate tectonics. Chemical fractionation and radioactive decay create isotopic differences during periods of isolation of one reservoir from another, whereas dynamic processes allowing mixing between reservoirs tend to reduce these differences. Observed isotopic characteristics reflect a balance between these opposing tendencies and provide constraints on the extent and timing of fractionation and mixing processes.

Plumbotectonics does not require interaction with a lower mantle or core reservoir over most of the Earth's lifetime, and, in fact, achieves a material balance consistent with no such exchange of material.

Important evidence of the amount and timing of crustal recycling, and of the residence times of mantle heterogeneities lies in the coupled $^{207} Pb^{204} Pb-^{206 Pb 204} Pb$ systematics. We believe that examination of the published data base fully supports our contention of significant bi-directional transport of material among terrestrial reservoirs. Plumbotectonics allows us to explore many aspects of reservoir interaction, and to identify parameters that provide meaningful constraints on mantle-crust differentiation. We put forth a compromise fit to many of the model variables in version IV, which can serve as a reference for future work.

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^☆: Presented at the Conference on “Isotope Tracers in Geochemistry and Geophysics” in honor of Professor Gerald J. Wasserburg's Sixtieth Birthday, March 23–25, 1987, Pasadena, California.

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The plumbotectonic model for Pb isotopic systematics among major terrestrial reservoirs—A case for bi-directional transport☆

Abstract

Geochim. Cosmochim. Acta

Earth Planet. Sci. Lett.

Earth Planet. Sci. Lett.

Earth Planet. Sci. Lett.

Geochim. Cosmochim. Acta

Earth Planet. Sci. Lett.

Earth Planet. Sci. Lett.

Earth Planet. Sci. Lett.

Geochim. Cosmochim. Acta

Earth Planet. Sci. Lett.

Earth Planet. Sci. Lett.

Geochim. Cosmochim. Acta

Econ. Geol.

Ann. Rev. Earth Sci.

Chemical aspects of the formation of the core

Phil. Trans. Roy. Soc. London

The depths of mantle reservoirs

Geochem. Soc., Spec. Publ.

Radiogenic isotopes: the case for crustal recycling on a near steady-state no-continental-growth Earth

Phil. Trans. Roy. Soc. London

The lead, neodymium and strontium isotopic structure of ocean ridge basalts

J. Petrol.

The bearing of lead isotopes on the source of granitic magma

J. Petrol.