Submarine landslide structures in neopleistocene deposits on the western slope of the Derbent basin of the Caspian Sea

Autor: V. E. Verzhbitskii, O. V. Levchenko, L. I. Lobkovskii
Rok vydání: 2008
Předmět:
Zdroj: Oceanology. 48:864-871
ISSN: 1531-8508
0001-4370
Popis: In the autumn of 2004, during cruise 19 of R/V Rift, an “SES-2000 standard” super high-resolution narrow-beam parametric profiler was applied for studies of the fine structure of the uppermost sediments for the first time in the Caspian Sea. In this paper, we discuss the latitudinal seismoacoustic profile across the western slope of the Derbent Basin in the region of the Russian part of the Yalama-Samur hydrocarbon field. In the upper part of the slope, in the Neopleistocene deposits, a series of overthrust covers with a step-wise structure of displacement surfaces (duplexes) was revealed. They seem to have been formed by gravity processes. We also suggest the existence of a “pushed wedge” type of structure of landslide origin formed by the Bakinian-Khvalynian deposits intruding into the overlying Holocene sediments. Sufficiently distinct signs of disintegration of the bottom sediments and landslide-slumping processes were distinguished within the Eopleictocene deposits on the steepest lower part of the slope. The data of seismoacoustic profiling indicate that submarine landslide processes proceeded on the western slope of the Derbent Basin during the Neopleistocene-Holocene, which may have retained their activity up to present. These facts should be considered when designing engineering constructions over the Yalama-Samur structure.
Databáze: OpenAIRE