New data on biostratigraphy, sedimentology and tectonics of the Russian
Far Eastern region (Lower Amurian terrane) are presented. This study
shows that sedimentary sequence of the terrane consists of interbedded
Radiolaria-bearing siliceous and volcaniclastic sediments spanning an
interval of over 90 million years. It is shown that accumulation of
radiolarian deposits on an oceanic plate was associated with alkaline
(intraplate) volcanism in the Jurassic, while the plate was drifting,
and with some are volcanism during the Early Cretaceous. The younger
siliceous rocks contain volcaniclastic material and indicate that the
studied sequence approached the trench in the Early Cretaceous
(Hauterivian-Barremian) and became accreted in the late Albian-early
Cenomanian. We describe and illustrate radiolarian species extracted fi
om 21 samples. A taxonomic list of 194 taxa and nine plates of
Jurassic-Early Cretaceous Radiolaria are presented.