Within-Plate Volcanic Rocks in Mesozoic Fold Sequences of Sikhote-Alin

摘要

This paper presents new geochemical and K-Ar data on alkali basalts, gabbro dolerites, and subalkali basalts located among the Mesozoic terrigenous-siliceous complexes of the Samarka and Pribrezhnyi zones of Primorye, south of 46° N. These rocks were emplaced as dikes, sheets, fissured intrusions, and volcanic pipes along fault zones in rift-grabens. They exhibit high contents of TiO_2 and HFSE (Zr, Nb, and Hf), as well as K, Ba, Rb, and Ce. Their composition and structural position are typical of plume-related within-plate magmatic associations.