Facies and depositional environment of the uppermost Jurassic stromatoporoid biostromes in the Zagros Mountains of Iran

Abstract

Abstract:The uppermost Jurassic (Tithonian) stromatoporoid biostromes occur as horizontally extended, up to 2.5 m thick lenses in a shallow marine carbonate sequence in the northwestern part of the Zagros Mountains, Iran. Stromatoporoids, accompanied by corals and calcareous algae, form floatstone and rudstone textures. The initial establishment of these potential reef-building organisms may have been related to substrate stabilization, likely due to exposure events. The stromatoporoids show two types of growth forms. Columnar forms, including the new species Cladocoropsis lindstroemi, are enclosed in a micritic matrix in low-energy environments. Laminar-domical forms piled up their skeletons on other species, or formed bulbous structures by encrusting other organisms. This study is the first description of Mesozoic stromatoporoids from Iran.

Sedimentary facies and biofacies of theTorinosuLimestone in theTorinosu area,KochiPrefecture,Japan

“…Similar low‐diversity (monospecific) aggregations of branching stromatoporoids are known, for example, from the Callovian Matmor Formation exposed at Makhtesh Gadol, southern Israel ( Shuqraia , Promillepora , and Parastromatopora ; Wood ) or from Tithonian deposits in the Zagros Mountains of Iran ( Cladocoropsis lindstroemi ; Kano et al . ).…”

Internal waves as controlling factor in the development of stromatoporoid-rich facies of the Apulia Platform margin (Upper Jurassic-Lower Cretaceous, Gargano Promontory, Italy)

“…While no evidence of surface storm waves has been seen (lack of shallow depth components), the turbulence events can be related to internal waves. Internal waves affected the buildups in two main ways: producing the debris-rich facies of LF1-S2 and pumping the nutrients needed by metazoans (mainly (Turnšek et al, 1981;Morsilli and Bosellini, 1997;Insalaco et al, 1997Insalaco et al, , 1999Olóriz et al, 2003;Lathuilière et al, 2005;Leinfelder et al, 2005;Kano et al, 2007;Olivier et al, 2008;Rusciadelli et al, 2011;Al-Awwad and Pomar, 2015;Basilone and Sulli, 2016a;San Miguel et al, 2017). Schematic depositional model of the Gargano margin during the Late Jurassic-Early Cretaceous (modified after Morsilli and Bosellini, 1997).…”

“…The sedimentological characteristics of this kind of reefs have been described in Italy: Central Apennines (Rusciadelli et al, 2011) and NW Sicily (Basilone and Sulli, 2016a), Slovenia (Turnšek et al, 1981), Austria: Northern Calcareous Alps (Schlagintweit and Gawlick, 2008); and in Czech Republic (Hoffmann et al, 2017). In Arabian Plate, the Upper Jurassic facies are reported from Saudi Arabia (Al-Awwad and Pomar, 2015, Rosales et al, 2018 and Iran (Kano et al, 2007).…”

“…Microbial fabrics are mostly thrombolite and microbial filaments. In the Zagros Basin, Iran,Kano et al (2007) reported stromatoporoid biostromes during Tithonian. The stromatoporoids are associated with corals and calcareous algae showing rudstone to floatstone texture.…”