New Origin of Thalassinoides Burrows (Gastropod Dwelling Structures) in the Qamchuqa Formation (Lower Cretaceous), Kurdistan Region, Northeastern Iraq
Journal: Journal of Oil and Gas Research Reviews
Year: 2025

This study documents the first significant occurrence of Thalassinoides ichnofossils in the Lower Cretaceous Qamchuqa Formation of northeastern Iraq. Preserved in coarse detrital limestones, terrigenous carbonates, and mixed sediments, these burrows are associated with coastal to shallow-marine ichnofacies, particularly Skolithos and Cruziana. Extensive burrow networks—horizontal tubes with vertical or inclined shafts—show features like eccentric swellings at branch points and smooth walls, rang