U–Pb zircon dating of felsic volcanic rocks from the Konachan Complex (Algan Mountains, northwestern Koryak Highland) confirmed their Late Miocene age (34.6 ± 0.5–38.8 ± 0.4 Ma, Priabonian). It is shown that these rocks are represented by moderate-potassium peraluminous (ASI = 1.23–1.30), moderate- and high-Mg varieties, frequently with high Cr and Ni contents. The Sr, Y, and Yb contents are similar to those of adakites. The high ¹⁴³Nd/¹⁴⁴Nd and low ⁸⁷Sr/⁸⁶Sr ratios in the rocks of the complex in combination with their trace and rare-earth distribution patterns suggest that metabasites weakly contaminated by sedimentary material were one source of silicic melt. The magmatic rocks of the Konachan Complex were formed during accretion of the terranes of the Olyutorka–Eastern Kamchatka island-arc system; the compression locked the upwelling front of continental asthenosphere, thus initiating crustal anatexis and silicic magmatism.

来自科纳查群（阿尔甘山脉，科里亚克高地西北部）的长英质火山岩的U–Pb锆石测年证实了它们的中新世年龄（36.3±0.5–38.8±0.4 Ma，P邦）。结果表明，这些岩石以中等钾高铝酸盐（ASI = 1.23–1.30），中等镁和高镁矿物为代表，并经常具有较高的铬和镍含量。Sr，Y和Yb的含量与钙铁矿的含量相似。高¹⁴³ Nd / ¹⁴⁴ Nd和低⁸⁷ Sr / ⁸⁶配合物中岩石中的Sr比及其痕量和稀土分布模式表明，被沉积物轻度污染的变质岩是硅质熔体的一种来源。Konachan复合体的岩浆岩是在Olyutorka-东部堪察加岛弧系统的地表增生过程中形成的。压缩作用锁定了大陆软流圈的上升流前沿，从而引发了地壳的无生气和硅质岩浆作用。