THE ZIRCON CHRONOLOGY OF THE INTRUSIVE MAGMATISM OF THE KANIN PENINSULA

Abstract

The Kanin Peninsula is an elevated block of the Timan Ridge where Precambrian sedimentary-metamorphic sequences and magmatic rocks, intruding them, form the Kanin Kamen Ridge. In the northwestern part of the Peninsula on the coast of the Barents Sea, there is a unique outcrop of two-mica granites, monzonitoids and lamprophyres cutting metaterrigenous rocks of the Upper Riphean Tabuyev series and overlain by Lower Permian limestones. To establish the age of magmatic rocks, U-Pb dating of zircons has been carried out by secondary ion mass spectrometry (SIMS) method. In zircons from granites, an age of 883 ± 16 Ma has been obtained, which corresponds to the beginning of the Late Riphean, and the subsynchronous formation of subalkaline rocks occurred in the Late Cambrian. The age of monzogabbro is 505 ± 7 Ma, and lamprophyres – 504±7Ma.

Keywords

• циркон
• граниты
• монцонитоиды
• лампрофиры
• п-ов канин
• тиман
• поздний рифей
• поздний кембрий
• u-pb изотопный возраст