Jurassic and Cretaceous stratigraphy of the New Siberian Archipelago (Laptev and East Siberian Seas): facies zoning and lithostratigraphy

Abstract

Mesozoic sections in the New Siberian Archipelago are important for understanding of the geology of underexplored shelf areas in the east of the Laptev Sea and in the west of the East Siberian Sea. They are reference sections for interpretation of seismic data in these regions. However, there are still many unresolved problems concerning the lithology, lateral extent, and age of Mesozoic deposits, as the sections have a complex structure and are heavily deformed. The performed research makes a basis for the first facies zoning of Jurassic and Cretaceous deposits in the New Siberian Islands and adjacent landmasses of continental Siberia at the junction of the Laptev and East Siberian Seas. The lithostratigraphic division of the Jurassic and Cretaceous is refined, being proposed for the first time for some stratigraphic intervals, and allows updating their lithostratigraphic division (or undertaking it for the first time for some stratigraphic intervals). Facies features of Jurassic and Cretaceous deposits allow the definition of three depositional series.

Jurassic palynoevents in the circum-Arctic region

“…Due to lack of data, these authors defined no dinocyst zones for the Hettangian to Pliensbachian and Aalenian to Bathonian intervals. Later, Nikitenko et al (2017Nikitenko et al ( , 2018a made comprehensive studies of the Jurassic-Cretaceous paralic successions of the New Siberian Islands based on dinocysts, foraminifera, ostracods, and miospores. Nikitenko et al (2015a, b) described the dinocyst biostratigraphy and paleoecology of the upper Oxfordian to middle Volgian interval of the Paksa section in Nordvik.…”