W. Loewenstein

Bio: W. Loewenstein is an academic researcher. The author has contributed to research in topics: Zirconium. The author has an hindex of 1, co-authored 1 publications receiving 7 citations.

Zirconolite, baddeleite, zircon and thorite of island arc quartz gabbro-norite-dolerites of Ayu-Dag intrusion (Mountain Crimea)

Abstract: Early Bajocian island arc quartz gabbro-norite-dolerites of Ayu-Dag contain syngenetic zirconolite and baddeleite. Zirconolite presents as Ca-dominant and uncommon Y-dominant (Y, Ca, Th, REE)2FeZr2Ti3O14. Two genetic types of zircon and thorite are developed. Predominant xenogenic zircon-I with thorite inclusions and a mass of lacunes — traces of reflow, is enriched with Hf, Th, Y, P (up to 6 wt.% HfO2, 5% ThO2, 6% Y2O3, 3% Р2О5). Thorite contains 7–9% UO2. Zircon and thorite of such composition are typical minerals of highly radioactive granites. Isotope age of zircon (xenogenic) is >2 billion years. Rare syngenetic zircon-II is sharply poor of Th, U, Y and Hf. So, basic magma of Ayu-Dag was contaminated with substance of Early Precambrian highly radioactive granites, which bodies are probabely located in the Mountain Crimea substructure.

Zirconolite, Baddeleyite, Zircon, and Thorite of Island-Arc Quartz Gabbronorite-Dolerites of the Ayu-Dag Intrusive, Crimean Mountains

Abstract: The Early Bajocian island-arc quartz gabbronorite-dolerites of the Ayu-Dag intrusive contain syngenetic zirconolite and baddeleyite. Zirconolite includes Ca-dominant and atypical Y-dominant (Y, Ca, Th, REE)2FeZr2Ti3O14 varieties. Two genetic types of zircon and thorite occur. The dominant xenogenic zircon-I with thorite inclusions and numerous melting traces (lacunes) is enriched in Hf, Th, Y, and P (up to 6 wt % HfO2, 5 wt % ThO2, 6 wt % Y2O3, 3 wt % P2O5). Thorite contains 7–9 wt % UO2. Zircon-I and thorite-I of similar compositions are typical minerals of highly radioactive granites. The isotope age of xenogenic zircon is more than 2 Ga. Rare syngenetic zircon-II is extremely depleted in Th, U, Y, and Hf. Thus, the Ayu-Dag basic magma was contaminated by Early Precambrian highly radioactive granites, whose bodies probably occur in the basement of Crimean Mountains.