Sedimentary evolution of Lake Van (Eastern Turkey) reconstructed from high resolution seismic investigations.

Cukur, Deniz, Krastel, Sebastian, Demirel-Schlüter, Feliz, Demirbag, E., Imren, C., Niessen, F. and Toker, M. and PaleoVan-Working Group (2013) Sedimentary evolution of Lake Van (Eastern Turkey) reconstructed from high resolution seismic investigations. International Journal of Earth Sciences, 102 (2). pp. 571-585. DOI 10.1007/s00531-012-0816-x.

[img] Text
10.1007_s00531-012-0816-x.pdf - Published Version
Restricted to Registered users only

Download (2345Kb) | Contact

Supplementary data:

Abstract

This paper presents results of a multi-channel seismic reflection survey at Lake Van and provides constraints on the sedimentary evolution of the lake. The geophysical data of the lake confirm the existence of three physiographic provinces: a shelf, a slope, and a deep, relatively flat basin. The most prominent features identified on the shelf and slope are clinoforms, submerged channels, as well as closely spaced lake floor depressions, reflecting a highly variable lake-level history. The morphological depressions are interpreted as resulting from subaquatic erosion by channelized, sediment-laden currents into horizontally bedded fan sediments. Submerged channels on the eastern shelf are interpreted as meandering-slope channels, probably as a consequence of a lake-level fall that exposed the shelf area. Clinoforms on the Eastern fan may represent relict deltas formed during stationary or slightly rising lake-level intervals. Merging subsurface imaging interpretation with morphological studies of exposed sediments reveals lake-level fluctuations of several hundreds of meters during the past ca. ~550 ka. The lake has three prominent basins (Tatvan, Deveboynu, and the Northern basin) separated by basement ridges (e.g., the Northern ridge). The seismic units in the Tatvan and Northern basins are dominated by alternations of well-stratified and chaotic reflections, while the Deveboynu basin subsurface consists mainly of chaotic units. The chaotic seismic facies are interpreted as mass-flow deposits, probably triggered by earthquakes and/or rapid lake-level fluctuations. The moderate-to-high-amplitude, well-stratified facies seen in the deeper parts of the basins are interpreted as lacustrine deposits intercalated with tephra layers. The occurrence of a clinoform in the deepest part of the lake suggests a major flooding stage of Lake Van more than ~400 ka ago. Seismic profiles from the deepest part of the lake basin show remarkably uniform and continuous stratigraphic units without any major erosional feature following the flooding event, indicating that the lake was never completely dry afterward and therefore significantly older than previously suggested.

Document Type: Article
Additional Information: WOS:000314899300010
Keywords: Geodynamics; Lake Van; Seismic data; Seismic facies; Lake-level fluctuations; Clinoform; Mass-flow; ANATOLIAN HIGH PLATEAU; STRATIGRAPHIC ANALYSIS; LE BOURGET; CLIMATE; RECORD; EARTHQUAKES; HISTORY; BASIN; SEA; INTEGRATION
Research affiliation: AWI
OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-GDY Marine Geodynamics
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1007/s00531-012-0816-x
ISSN: 1437-3254
Date Deposited: 24 Jun 2011 10:31
Last Modified: 18 May 2017 12:57
URI: http://oceanrep.geomar.de/id/eprint/11935

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...