
Uranium-Lead Geochronology on Monacite of Granites of the Lypnyazka Massif and its Framing (Ingul Megablock of the Ukrainian Shield)
Author(s) -
L.M. Stepanyuk,
AUTHOR_ID,
S.I. Kurylо,
V.O. Syomka,
Т.I. Dovbush,
S.M. Bondarenko,
Oksana V. Kovtun,
I.M. Kotvitska,
AUTHOR_ID,
AUTHOR_ID,
AUTHOR_ID,
AUTHOR_ID,
AUTHOR_ID,
AUTHOR_ID,
AUTHOR_ID
Publication year - 2021
Publication title -
geohìmìâ ta rudoutvorennâ
Language(s) - English
Resource type - Journals
eISSN - 2617-3395
pISSN - 2224-6487
DOI - 10.15407/gof.2021.42.071
Subject(s) - massif , geology , geochemistry , leucogranite , pegmatite , gneiss , geochronology , syncline , shield , precambrian , petrology , geomorphology , metamorphic rock , structural basin
The Lipnyazka massif is located in the Dobrovelychkivsky district of the Kirovohrad region, v. Lipnyazka and further south. Structurally, it is located within the Bratskyy Synclinorium of the Ingul megablock and coincides with the Mikhailovsky anticline. The main petrotype of the massif rocks are porphyry-like granites, often with a gneiss-like texture, aplito-pegmatoid, pegmatoid granites and pegmatites. The latter most often form secant vein bodies. Uranium-lead isotopic dating of granitoids of the Lipnyazka granite massif has been performed, with which a number of deposits and ore occurrences of rare elements, primarily lithium, are spatially and probably genetically connected. The age of porphyry-like granites (2032 ± 6 million years), which is the main petrotype of rocks distributed in the area of the village of Limestone and pegmatoid granites (2027 ± 1 million years), which cut porphyry-like in the form of vein bodies. Aplithoid framed granites (2046 ± 8 million years old), common in the area of the mouth of the Sukhyi Tashlyk River (Dobryanka village), are somewhat older. Based on the results of determining the isotopic composition of strontium in the accessory apatite of granites, a conclusion was made about the upper crust source of granites of the Lipnyazka massif (87Sr/86Sr – 0.730-0.785).