Isotope geochemistry and deep sources of subalkaline and alkaline rocks from the Paleogene contrasting series of the Amguema-Kanchalan volcanic field, Okhotsk-Chukotka volcanic belt

Basaltoids of the bimodal suite are mafic to inter mediate sodium trachybasalts (including high Ti) and trachyandesibasalts. The acid members of the bimodal suite are represented within the AKVF by subalkaline (trachyandesidacite (trachyte)trachydacitetrachy rhyolite) and alkaline (pantelleritecomenditealka line granite) rock associations. Previous studies revealed significant differences in the trace element minerals and whole rock compositions of these rocks ([57] and others).