EARLY AND MIDDLE JURASSIC (PLIENSBACHIAN TO BAJOCIAN) RADIOLARIA FROM CHERTS OF KISELEVKA-MANOMA ACCRETIONARY COMPLEX (AMUR RIVER, EASTERN RUSSIA)

Abstract

The lower part of chert sequence of Kiselevka-Manoma accretionary complex, Sikhote-Alin system (Eastern Russia) is characterized by the following radiolarian assemblages (in ascending order of age):

1. Early Pliensbachian to early Toarcian with Parahsuum izeenze, Bagotum maudense and Katroma clara.

2. Early Toarcian with Bistarkum rigidium and Citriduma hexaptera.

3. Middle-late Toarcian to early-middle Aalenian with Paronaella grahamensis, Praeparvicingula gigantocornis and Hsuum exiguum.

4. Early-middle Aalenian with Parahsuum? grande, Parahsuum cruciferum and Hsuum altile.

5. Late Aalenian with Parahsuum? hiconocosta, Transhsuum hisuikyoense and Nassellaria gen. et sp. indet. 1.

6. Early-middle Bajocian with Sella beniderkoulensis and Emiluvia splendida. New species Olanda inflata Bragin, n. sp. is described from this assemblage.

Studied radiolarian assemblages are Tethyan in affinity, which allows to utilize the low-latitude zonal radiolarian scales for the Jurassic (Baumgartner et al., 1995b; Carter et al., 2010). The total stratigraphic range of chert sequence of the Kiselevka-Manoma accretionary complex can be estimated as Early Jurassic (Pliensbachian-early Toarcian)-Early Cretaceous (Barremian).