1. Morphology versus UPb systematics in zircon: a high-resolution isotopic study of a zircon population from a Variscan dike in the Central Alps
- Author
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Paul J. Bossart, Rudolf H. Steiger, Martin Meier, and Felix Oberli
- Subjects
Dike ,geography ,education.field_of_study ,geography.geographical_feature_category ,Population ,Geochemistry ,Crust ,Diorite ,Igneous rock ,Geophysics ,Space and Planetary Science ,Geochemistry and Petrology ,Magma ,Earth and Planetary Sciences (miscellaneous) ,education ,Geology ,Petrogenesis ,Zircon - Abstract
UPb isotopic measurements on individual zircon crystals combined with morphological analyses permit the identification of three distinct components within the zircon population of the Saedelhorn diorite, a Variscan dike from the western Gotthard (Central Alps, Switzerland): (i) 94% of the grains in the zircon population are elongate crystals with pronounced skeletal morphology indicative of rapid growth from a supercooled melt. (ii) 5% of the population consist of turbid, mostly subhedral zircons frequently showing D-type morphology (classification according to Pupin and Turco [1]) and elevated uranium contents compared to the skeletal variety. Single-crystal and multi-grain UPb isotopic data of group (i) and (ii) zircons define an intrusion age of 293 +5/−4 m.y. for the dike. (iii) Rare, transparent zircon crystals (
- Published
- 1986
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