Journal ArticleDOI
Phase Transformations and Differentiation in Subducted Lithosphere: Implications for Mantle Dynamics, Basalt Petrogenesis, and Crustal Evolution
TLDR
In this article, the Nd, Sr, and Pb isotopic characteristics of MORBs are explained on the basis of this model, which provides a future source region of mid-ocean ridge basalt magmas on a timescale of 10 years.Abstract:
Mantle pyrolite differentiates at mid-oceanic ridges to form a layered lithosphere consisting of a basaltic crust, immediately underlain by harzburgite and further underlain by pyrolite which has experienced depletion only of highly incompatible elements (e.g., Rb, light REE). The body forces driving subduction are concentrated mainly in the upper cool, brittle layer of lithosphere, comprised of basalt and harzburgite. The lower layer of relatively ductile pyrolite is stripped off during subduction and resorbed into the upper mantle. This material, which is depleted in highly incompatible elements, provides a future source region of mid-ocean ridge basalt magmas on a timescale of 10⁹ years. The Nd, Sr, and Pb isotopic characteristics of MORBs are explained on the basis of this model. The slab, which sinks to ~600 km, is comprised mainly of former basalt and harzburgite. These differentiated layers undergo a significantly different series of phase transformations to those experienced by mantle pyrolite. Th...read more
Citations
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Chemical and isotopic systematics of oceanic basalt : implications for mantle composition and processes
TL;DR: In this article, trace-element data for mid-ocean ridge basalts and ocean island basalts are used to formulate chemical systematics for oceanic basalts, interpreted in terms of partial-melting conditions, variations in residual mineralogy, involvement of subducted sediment, recycling of oceanic lithosphere and processes within the low velocity zone.
Journal ArticleDOI
Chemical and isotopic systematics of oceanic basalts. Implications for Mantle Composition and Processes
Journal ArticleDOI
Nb and Pb in oceanic basalts: new constraints on mantle evolution
TL;DR: In this paper, the authors proposed a new constraint on mantle composition: the differentiated part of the mantle, chemically depleted after separation of the major portion of the continental crust, was subsequently internally rehomogenized.
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The origin of ocean island basalt end-member compositions: trace element and isotopic constraints
TL;DR: In this paper, the trace element and isotopic constraints for the three OIB end-members suggest a relatively simple model for their origin, where the dominant component in all OIB is ancient recycled basaltic oceanic crust which has been processed through a subduction zone.
Journal ArticleDOI
The ultrapotassic rocks: Characteristics, classification, and constraints for petrogenetic models
TL;DR: In this paper, the chemical properties of ultrapotassic rocks are defined using the chemical screens K 2 O > 3 wt.%, MgO > 3 Wt.% and Na 2 O/Na 2 O 2 > 2 for whole-rock analyses.
References
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Book
Conduction of Heat in Solids
H. S. Carslaw,John Conrad Jaeger +1 more
TL;DR: In this paper, a classic account describes the known exact solutions of problems of heat flow, with detailed discussion of all the most important boundary value problems, including boundary value maximization.
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Elasticity and constitution of the Earth's interior
TL;DR: In this paper, the authors derived a general equation for the variation of the quantity,, in a homogeneous gravitating layer with an arbitrary gradient of temperature, and discussed the parameters of this equation in terms of the experimental and theoretical relations for solids.
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Integrated Models of Basalt Petrogenesis: A Study of Quartz Tholeiites to Olivine Melilitites from South Eastern Australia Utilizing Geochemical and Experimental Petrological Data
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Trace element fractionation and the origin of tholeiitic and alkaline magma types
TL;DR: In this article, it was shown that the abundance of large ion elements in alkaline basalts cannot be consistently explained by fractional crystallization processes and that these characteristics are produced by previous partial melting episodes.