Article Abstract:
Scientists have applied neon-isotope systematics research methods to determine the metasomatic character of apatite grains in spinel-lherzolite xenoliths from the Australian lithospheric mantle. They have discovered that the neon-isotope signature of the apatite is like that found with plume-related volcanism in Hawaii. However, coexisting mineral phases and non-apatite-bearing lherzolites are more like mid-ocean ridge basalts in isotope signature. The research indicates that the metasomatizing agent is sourced from the plume-like substance.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
Metasomatism of harzburgite xenolith from Kimberley, South Africa occurred at the same time as the migration of the kimberlite magma in which the xenolith is found. Group I kimberlite magmatism thus shares a common origin with the metasomatism which accompanies it, rather than being related to earlier igneous events. A metasomatic veined harzburgite is investigated with plane polarized light and by radioisotope methods, revealing the presence and age of zircon crystals and other features.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
The integration of hafnium and oxygen isotopes, all measured in situ on the same, precisely dated detrital zircon grains is reported. The results revealed that the crust generation in part of Gondwand was limited to major pulse at 1.9 and 3.3 Gyr ago, and that zircons crystallized during repeated reworking of crust formed at these times.
User Contributions:
Comment about this article or add new information about this topic: