Cenozoic history of the Bering Sea and its northwestern margin

Abstract

Tectonic reconstructions based on the geodynamic analysis of geologic, paleomagnetic, structural and kinematic data of Cenozoic age from the western Bering Sea region are proposed in the present paper. The most active tectonic and magmatic processes took place in the Komandorsky segment of the Bering Sea, exemplified by the Late Cretaceous–Early Eocene Olutorsky Arc and Eocene–Oligocene Govena–Karaginsky Arc, which was built on the structures of the Olutorsky Arc. A model of the complex collision of these two arcs with the paleocontinental margin, which considers rotations of the geological blocks from the various structural zones of the western margin of the Bering Sea in the horizontal plane (paleomagnetic data), was proposed by the authors. According to this model the collision of the flanks of the Olutorsky and Govena–Karaginsky arcs took place in the Eocene, before the collision of the central parts in the Miocene.

Chapter 6 Phanerozoic palaeoenvironment and palaeolithofacies maps of the Arctic region

“…The Anadyr-Bristol arc terrane was formed between Chukotka and Alaska at the northern Pacific margin (Zonenshain et al 1990;Parfenov et al 1993Parfenov et al , 2001Marlow et al 1994;Nokleberg et al 2005). Back-arc extension, behind the Aleutian arc, formed the Bering Sea between Chukotka and Alaska (Ben-Avraham & Cooper 1981;Zonenshain et al 1990;Cooper et al 1992;Chekhovich et al 1999;Walker et al 2003;Verzhbitsky et al 2007). According to Oldow et al (1989), fragments of the Cretaceous Kula plate were captured behind the volcanic composite complex, formed at 55-50 Ma.…”

“…Spreading continued in the Bering Sea (Ben-Avraham & Cooper 1981;Zonenshain et al 1990;Cooper et al 1992;Chekhovich et al 1999;Walker et al 2003;Verzhbitsky et al 2007). Deposition of coarse-grained, fine-grained and mixed clastics continued in shallow-water (northern part) and deep-water (southern part) environments.…”

Paleomagnetism of the Cretaceous rocks from Cape Kronotskiy, East Kamchatka and reconstruction of terrane trajectories in the NE Pacific area

“…Numerous authors have discussed the number, location, and configuration of tectonic plates in the Pacific basin in terms of seismic data, paleomagnetic data, magnetic isochrons, and fault orientation data (Chapman and Solomon, 1976;Natal'in, 1985, 1986;Natal'in et al, 1986;Engebretson et al, 1985;Watson and Fujita, 1985;Heiphetz et al, 1992a, b;Didenko et al, 1993;Riegel et al, 1993;Geist and Scholl, 1994;Mackey et al, 1997;Perchesky et al, 1997;Levashova et al, 1998;Chekhovich et al, 1999;. By sampling paleomagnetic units from an out board terrane and then comparing these results with terrane trajectories calculated from finite-rotation models for known plates of the ancient pacific basin it was hoped that some insight could be gained into the past plate tectonic configuration of this complex region.…”