Abstract

Albian–Cenomanian siliciclastic-crabonate sediments of northwest Rayen in the south Kerman, southeast Iran (526 m) are classifiable to three informal units. Unit one includes conglomerates, sandstones and siltstones with limestone and marl intercalations. Unit two compose of Orbitoline bearing limestones with rudist, belemnoid and ammonite bioclasts. Alternations of pelagic limestones and sandstones formed third unit. An assemblage of continental to marine trace fossils have been found in the first and third units of the studied section, that include Koilosoma isp., Ophiomorpha isp., Palaeophycus isp., Planolites isp., Skolithos isp., Taenidium isp., and Thalassinoides suevicus. These trace fossils belongs to Scoyenia, Skolithos and Cruzian ichnofacies. Abundant Thalassinoides-Phycodes compound trace fossil, however have been found in the third unit. Box-worked Thalassinoides burrow system ends to multi- branched Phycodes borrows. This compound trace fossil is interpreted as feeding-domicile biogenic structure, so that Thalassinoides domichnium ends to Phycodes excavated feeding burrows. Compound Thalassinoides-Phycodes trace fossil extended in the deeper parts of offshore shelf sediments in the studied section. Based on ichnological data, it seems that Albian–Cenomanian sediments of northwest Rayen deposited in the deepening upward sequence.