Bioerosive structures in orbitolinid foraminifera: examples from the Lower Cretaceous of Central Iran

Abstract

Abstract. Lower Cretaceous orbitolinid assemblages from Central Iran yield various bioerosional structures. The omnipresent traces of different boring taxa and groups (e.g., sponges, calcimicrobes, incertae sedis) represent a characteristic feature of the investigated thin-section material. The assemblage can be attributed to the Entobia ichnofacies dominated by borings assigned to the activity of sponges. The boring galleries are often concentrated in a plane parallel to the test surface, along the boundary of the marginal and the central zone of the orbitolinid tests. The borings are observed in foraminiferan-dasycladalean wackestones to poorly washed-out packstones, which can be referred to a subtidal palaeoenvironment.

Microbiostratigraphy, microfacies analysis and lateral basin evolution of Lower Cretaceous deposits in the south of Kerman region, SE Iran

“…In general, the identified foraminifera assemblage in the studied area shows higher diversity than other studied areas in CEIM, Alborz, Zagros and kopet Dagh structural zones (Yazdi-Moghadam and Amiri, 2010; Roozbahani, 2011;Rami et al, 2012;Bucur et al, 2013;Schlagintweit et al, 2013aSchlagintweit et al, , 2013bWilmsen et al, 2013;Khodashenas et al, 2014;Schlagintweit and Wilmsen, 2014;Babazadeh and Dehej, 2015;Hanifzadah et al, 2015;Hosseini et al, 2016;Hassani, 2016a, 2016b;Yavarmanesh et al, 2017;Yazdi-Moghadam et al, 2017;Gheiasvand et al, 2020;Moosavizadeh et al, 2020).…”

“…The biostratigraphy and paleoecology of some localities in CEIM were carried out by some authors ( Bucur et al, 2003;Yazdi-Moghadam and Amiri, 2010;Bucur et al, 2012;Rami et al, 2012;Schlagintweit et al, 2013aSchlagintweit et al, , 2013bSchlagintweit et al, , 2013cWilmsen et al, 2013;Khodashenas et al, 2014;Hanifzadah et al, 2015;Hosseini et al, 2016;Hairapetian et al, 2018).…”