Isfahan Province, Bagher Abad village, Bidestan Member (Triassic of Iran)

Where: Isfahan, Iran (33.1° N, 52.0° E: paleocoordinates 29.4° N, 40.0° E)

• coordinate stated in text

• small collection-level geographic resolution

When: Nayband Formation, Norian (228.0 - 208.5 Ma)

• the Triassic deposits are overlain with a distinct angular unconformity by the Lower Cretaceous deposits, whereas Jurassic sediments are missing almost completely. The unit of conglomerate at the base of the Lower Cretaceous contains pebbles of carbonate and siliciclastic rocks without any sign of the Jurassic fossils.

• member-level stratigraphic resolution

Environment/lithology: reef, buildup or bioherm; lithified limestone and lithified sandstone

• Bidestan Member is about 11m thick and it starts with oolitic limestones containing abundant spherical hydrozoan Heterastridium spp. indicating the Norian age. Biostromal bioconstructions are also present. Sponges and corals are the main reef building organisms in the biostromes
• Oolithic limestones, sandstones and reefal limestones with numerous algae, calcareous sponges and corals.

Size classes: macrofossils, mesofossils

Primary reference: M. Mannani and M. Yazdi. 2009. Late Triassic and Early Cretaceous sedimentary sequences of the northern Isfahan Province (Central Iran): stratigraphy and paleoenvironments. Boletín de la Sociedad Geológica Mexicana 61(3):367-374 [W. Kiessling/M. Krause]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 138966: authorized by Wolfgang Kiessling, entered by Mihaela Krause on 05.02.2013

Creative Commons license: CC BY (attribution)

Taxonomic list

Hydrozoa
 Milleporina - Heterastrididae
Heterastridium spp. Reuss 1865 fire coral
Anthozoa
 Scleractinia - Astraeomorphidae
Astraeomorpha crassisepta Reuss 1854 stony coral
 Scleractinia - Reimaniphylliidae
Distichophyllia cf. norica Frech 1890 stony coral
Retiophyllia clathrata Emmrich 1853 stony coral
 Scleractinia - Pamiroseriidae
Crassistella juvavica Frech 1890 stony coral