The picritic volcanic suite of Baffin Island is comprised of two different types of magmas which are analogous to N and E-MORB. Although these two picritic lavas-types are spatially intermixed in the stratigraphic succession, they are distinct in terms of light rare earth elements (LREE), K/Ti and $ sp{87}$Sr/$ sp{86}$Sr ratios. N-type lavas are depleted in LREE and have K/Ti ratio 0.5 and $ sp{87}$Sr/$ sp{86}$Sr ratios ranging between 0.7032 and 0.7039. Olivine fractionation and partial melting models involving a single homogeneous source can not reproduce the trace element differences between these two magma types. The generation of N and E-type magmas is most easily explained by small scale mantle heterogeneity. A possible model for the nature of the source is that of the head of a mantle plume which has an entrained depleted mantle.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.60080 |
| Date | January 1991 |
| Creators | Robillard, Isabelle |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Geological Sciences.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001238384, proquestno: AAIMM67817, Theses scanned by UMI/ProQuest. |
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