Oligo-Miocene carbonate platform evolution in the northern margin of the Asmari intra-shelf basin, SW Iran

Lower Eocene carbonate ramp clinoforms of the southern Tethys; Zagros Foreland Basin, SW Iran: Sequence stratigraphy architecture, basin physiography and carbonate factory controlling parameters

“…was flourished. They appeared together with coralline red algae in the context of the Rupelian biostrome and Chattian build‐ups (Allahkarampour Dill et al, 2018; Shabafrooz et al, 2015; van Buchem et al, 2010), which constructed a thick‐bedded to massive and poorly stratified rock succession.…”

“…This carbonate factory, at an estimated water depth of approximately 20-40 m, produced the highest volume of carbonate production/accumulation compared to the deeper and shallower zones (Figure 10a Based on lateral facies heterogeneities and depositional geometry, this association is interpreted to have accumulated in a lagoonal shallow-water back-bank setting (Beavington-Penney et al, 2006;Jorry, 2004;Jorry et al, 2006;Racey, 2001). In general, a high percentage of porcelaneous foraminifera in FA.IV reflects a shallow-water, euphotic zone of the inner ramp setting (platform top; Allahkarampour Dill et al, 2018;Janson et al, 2010;Pomar, 2001aPomar, , 2001bPomar et al, 2012;Tella et al, 2022), adapted to sea grass meadows (Brandano, Frezza, Tomassetti, Pedley et al, 2009;Pomar et al, 2014). Such shallow water, vegetation-covered substrates have been documented based on indirect evidence provided by the 6.5 | FA.V: Allochthonous-dominated high-energetic inner ramp FA.V occurs in tabular cm-to-dm-thick limestone to sandy limestone beds (Figures 12a,b and 13a,b), dominated by well-sorted and well-rounded allochthonous components such as ooids, small miliolids, peloids and skeletal detritus (bivalves and gastropods; Figures 13c and 15a,c).…”

“…The high diversity and abundance of flat rotaliids such as Discocyclina and Actinocyclina , Nummulites , Assilina and Operculina , together with a small proportion of planktonic foraminifera, place this facies under low‐light and deeper‐water conditions (oligophotic zone; Allahkarampour Dill et al, 2018; Bassi et al, 2007; Beavington‐Penney & Racey, 2004; Brandano & Corda, 2002; Buxton & Pedley, 1989; Corda & Brandano, 2003; Janson et al, 2010; Mateu‐Vicens et al, 2012; Pomar, 2001b; Pomar et al, 2012, 2014; Romero et al, 2002). Fragmented, unsorted and poorly preserved tests of such rotaliids within a mud‐dominated matrix, the scarce shallow‐water components and bedding geometry (the slope clinoforms) reflect this FA to have mainly accumulated in the lower ramp slope setting (Beavington‐Penney & Racey, 2004; Mateu‐Vicens et al, 2008; Pomar, 2001a, 2001b; Racey, 2001; Tella et al, 2022) under an active sediment transport mechanism, which was presumably induced by both internal waves (IWs) and the bathymetric gradient (Mateu‐Vicens et al, 2012; Pomar, 2020).…”

“…Based on lateral facies heterogeneities and depositional geometry, this association is interpreted to have accumulated in a lagoonal shallow‐water back‐bank setting (Beavington‐Penney et al, 2006; Jorry, 2004; Jorry et al, 2006; Racey, 2001). In general, a high percentage of porcelaneous foraminifera in FA.IV reflects a shallow‐water, euphotic zone of the inner ramp setting (platform top; Allahkarampour Dill et al, 2018; Janson et al, 2010; Pomar, 2001a, 2001b; Pomar et al, 2012; Tella et al, 2022), adapted to sea grass meadows (Brandano, Frezza, Tomassetti, Pedley et al, 2009; Brandano, Frezza, Tomassetti, et al, 2009; Pomar et al, 2014). Such shallow water, vegetation‐covered substrates have been documented based on indirect evidence provided by the disc‐shaped soritid Orbitolites , as strong evidence of sea grass (Beavington‐Penney & Racey, 2004), together with alveolinids, miliolids and peneroplids (Allahkarampour Dill et al, 2018; Beavington‐Penney et al, 2006; Beavington‐Penney & Racey, 2004; Jorry, 2004; Pomar et al, 2014).…”

Early Miocene larger benthic foraminifera from the northwestern Tethyan Seaway (NW Iran): new findings on Shallow Benthic Zone 25

“…Associated with the other shallow-marine biota (e.g., echinoderms, pelecypods, gastropods, coralline algae), LBF characterize widespread platform carbonates of the Oligo-Miocene age which are known under different formational names from central and southern Iran, e.g., Asmari, Mishan, and Gachsaran formations (Zagros Mountains), or Qom Formation (Central Iran). Attempts for detailed stratigraphy, and palaeoenvironmental studies of these platform carbonates in Iran, have been made by several authors and are still in progress (e.g., Ehrenberg et al 2007 ; Van Buchem et al 2010 ; Shabafrooz et al 2015 ; Allahkarampour Dill et al 2018 ; Yazdi-Moghadam et al 2018a , b ; Basso et al 2019 ; Akbar-Baskalayeh et al 2020 ). The present study makes an important contribution to this study process and reports the occurrence of hyaline and porcelaneous LBF recovered from three outcrop sections in the Hamedan–Miandoab area, NW Iran.…”