Ichnology of lower Jurassic beach deposits in the Shemshak Formation at Shahmirzad, southeastern Alborz Mountains, Iran

Journal article


Publication Details

Author(s): Fürsich F, Wilmsen M, Seyed-Emami K
Journal: Facies
Publication year: 2006
Volume: 52
Journal issue: 4
Pages range: 599-610
ISSN: 0172-9179
Language: English


Abstract


A 19 m thick package of well-sorted lowermost Jurassic (Hettangian-Lower Sinemurian?) sandstones within the Shemshak Formation of the southeastern Alborz Mountains displays features characteristic of foreshore to upper shoreface environments such as tabular bedding, low-angle lamination, trough cross-stratification, parting lineation, and oscillation ripples. In contrast to most other beach successions recorded in the literature the sandstones contain a trace fossil assemblage characterised by low abundance but comparatively high diversity. The assemblage, comprising 14 ichnotaxa, is dominated by Palaeophycus heberti, Rhizocorallium irregulare, Gyrochorte comosa, and Parahaentzschelinia surlyki. Contrary to predictions, which assume a dominance of suspension-feeders in such high-energy environments, the trace fossil assemblage represents a variety of ethological groups ranging from suspension-feeders to deposit-feeders, detritus-feeders, scavengers, and a possible trap constructor (Ctenopholeus), whereby deposit-feeders predominate. This anomaly is explained by a high amount of organic detritus in the sediment, indicated by abundant plant material, and a position of the beach in the vicinity of a river mouth. © Springer-Verlag 2006.



FAU Authors / FAU Editors

Fürsich, Franz Prof. Dr.
Naturwissenschaftliche Fakultät
Wilmsen, Markus PD Dr.
Naturwissenschaftliche Fakultät


Additional Organisation
Lehrstuhl für Paläoumwelt


External institutions with authors

University of Tehran


How to cite

APA:
Fürsich, F., Wilmsen, M., & Seyed-Emami, K. (2006). Ichnology of lower Jurassic beach deposits in the Shemshak Formation at Shahmirzad, southeastern Alborz Mountains, Iran. Facies, 52(4), 599-610. https://dx.doi.org/10.1007/s10347-006-0082-0

MLA:
Fürsich, Franz, Markus Wilmsen, and Kazem Seyed-Emami. "Ichnology of lower Jurassic beach deposits in the Shemshak Formation at Shahmirzad, southeastern Alborz Mountains, Iran." Facies 52.4 (2006): 599-610.

BibTeX: 

Last updated on 2018-08-08 at 01:26