ГАББРО-ГРАНОДИОРИТОВЫЙ МАГМАТИЧЕСКИЙ КОМПЛЕКС КРОНОЦКОЙ ПАЛЕОДУГИ (ВОСТОЧНАЯ КАМЧАТКА): ВОЗРАСТ, СОСТАВ И ТЕКТОНИЧЕСКОЕ ПОЛОЖЕНИЕOctober 2022Геотектоника 5:50-75DOI: 10.31857/S0016853X22050083статья
Статья опубликована в журнале из списка RSCI Web of Science
Аннотация:New U‒Pb (SIMS and LA-ICP-MS) geochronological data from the study of accessory zircons from granodiorites and detrital zircons from schlich samples from the Shipunsky massif in the Eastern Kamchatka, were obtained. The age of accessory zircons from amphibole-biotite granodiorites from 49 to 44 Ma, was estimated. Detrital zircons have the Late Paleocene–Early Eocene age from ~57 to ~49 Ma. Based on the geological and geochronological data, it is proposed that the formation of the massif occurred in two stages: intrusion of gabbroids occurred at the interval 56‒51 Ma, and intrusion of quartz diorites and granodiorites at age 49‒44 Ma. Petrographic and geochemical characteristics of the Upper Cretaceous–Eocene volcanites of the Shipunsky Peninsula and granitoids of the Shipunsky massif indicate their formation in suprasubduction setting. The granitoids of the Shipunsky massif belong to the I-type granites. The Shipunsky massif was formed as a part of the intraoceanic Kronotsky paleoarc during the Paleocene–Eocene in two stages. During the collision of the southern segment of the Kronotsky paleoarc with the continental margin of Kamchatka, the rocks of the massif were deformed and brought up to the surface.