Chemical heterogeneity of the Emeishan mantle plume: Evidence from highly siderophile element abundances in picrites
Access Status
Authors
Date
2013Type
Metadata
Show full item recordCitation
Source Title
ISSN
Remarks
NOTICE: this is the author’s version of a work that was accepted for publication in Journal of Asian Earth Sciences resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Asian Earth Sciences, Vol. 79A (2013). DOI: 10.1016/j.jseaes.2013.09.009
Collection
Abstract
Highly magnesian lavas or picrites have the potential to preserve important information about the origin and thermochemical state of the mantle source(s) of large igneous provinces. We have conducted a comprehensive study of highly siderophile element (HSE) concentrations in picrites from the ca. 260 Ma Emeishan large igneous province. We show that HSE abundances in the Emeishan picrites are greater than those in mid-ocean ridge basalts (MORBs) and parental melts of Hawaiian picrites, but are similar to those in komatiites. The picrites have two types of C1-normalized HSE patterns: (a) type 1, as represented by the Muli picrites is similar to that of the primitive upper mantle; (b) type 2, as represented by the Dali picrites resembles East Greenland and Iceland picrites. Pt/Ir and Pd/Ir ratios in the type 2 picrites are higher than those in type 1 picrites. The primary melt compositions of the studied samples have been estimated by back-addition of equilibrium olivine. The calculated HSE abundances of the parental liquids of the Dali and Muli picrites are higher than those of the parental melts to Hawaiian picrites. Along with previously published isotopic data, our study provides further evidence for chemical heterogeneity of the Emeishan mantle plume.
Related items
Showing items related by title, author, creator and subject.
-
Shellnutt, J.; Usuki, T.; Kennedy, Allen; Chiu, H. (2015)High seismic velocity layers within the lower crust (i.e. ~40. km) of the Yangtze Block are interpreted as mafic underplated rocks derived from the Late Permian Emeishan mantle plume. However, the region experienced a ...
-
Luttinen, A.; Heinonen, J.; Kurhila, M.; Jourdan, Fred; Mänttäri, I.; Vuori, S.; Huhma, H. (2015)The Jurassic Vestfjella dyke swarm at the volcanic rifted margin of western Dronning Maud Land represents magmatism related to the incipient Africa–Antarctica rift zone; that is, rift-assemblage magmatism of the Karoo ...
-
Wang, X.; Wilde, Simon; Xu, B.; Pang, C. (2015)© 2015 Elsevier B.V. Continental basalts generally display enrichment of fluid-mobile elements and depletion of high-field-strength elements, similar to those that evolved in the subduction environment, but different from ...