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The metamorphic complexes of eastern Kamchatka exposed on the Khavyven Highland and Karaginsky Island, as well as on the Kamchatka and Ozernoi peninsulas, compose large (up to 1.5 km) elon gated blocks spatially associated with ophiolitic peridotite and gabbroic rock bodies (the Khavyven Highland and Karaginsky Island) or make up isolated fragments and blocks among serpentinite melange (the Ozernoi and Kamchatka peninsulas). The degree of metamorphism of the primary rocks varies from the green schist/amphibolite boundary facies (Karaginsky Island and the Khavyven Highland) to the high pressure amphibolite facies (the Ozernoi and Kamchatka peninsulas). Our first U-Pb SHRIMP zircon data on the metamorphic and igneous rocks in eastern Kamchatka and the analysis of previous studies testify to two time intervals of the manifestation of metamorphism in the studied region. The first stage of metamorphism (80-75 Ma) coincides with the formation of the ophiolitic gabbro and peridotites (100-70 Ma) that compose the eastern Kamchatka ophiolite zone. The metamorphic rocks of this stage comprise fragments and blocks in the serpentinite melange (the Kamchatka and Ozernoi penin sulas). They are represented by high pressure (up to 8-10 kb) garnet amphibolites related to the rocks of the ophiolite association (gabbro, basalts, tuffs, and siliceous rocks). The second stage of magmatism and subse quent metamorphism embraces the time interval of 70-50 Ma. This stage is associated with the formation of vol canics of the tholeiitic, calc alkaline, and subalkaline series, zonal gabbro-peridotite intrusions (70-60 Ma, and metamorphism of moderate pressures (up to 5-7 kb) and temperatures (400-600°C) typical of rock com plexes in the Khavyven Highland and on Karaginsky Island (55-50 Ma). According to the new U-Pb zircon isotope data, the most ancient protolith of metamorphic complexes in eastern Kamchatka is represented by the volcanosedimentary rocks of Karaginsky Island (181 ± 1.8 Ma). The age of the protolith of the Khavyven Highland is 100 ± 11 Ma. The age of the zircons from the garnet amphibolites of the Kamchatka Peninsula (77.6 ± 4.6 Ma) corresponds to the evolution period of the ophiolites of the gabbro-peridotite complex.The petrography and mineralogy of the metamor phic rocks. The main rock type of the Gnunvayam Group is represented by chlorite-epidote-amphib ole-plagioclase schists. The epidote-chlorite-pla gioclase-amphibole (± biotite) and epidote-amphib ole-chlorite-plagioclase schists are subordinate. The epidote and chlorite quartzites, as well as epidotebiotite-amphibole-plagioclase schists, are rare.

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