Revisiting the “Gercus Basalt within the Eocene Gercus Formation”: Implications for sedimentary origin of a basaltic body, Kurdistan Region, Northern Iraq

•A previously described intrusive basaltic body is re-studied.•The re-study proved that it consists of sedimentary rocks (greywacke sandstone).•The greywacke transported from remote volcanic source to its present area.•More than ten evidences are found to prove its sedimentary origin.•These evidence are such as content of bitumen, conglomerate imbricated pebbles.•Other evidences are presence of graded beds, parallel and planer bedding and ooids.•More evidences are absence of basaltic flows and chilled borders and others.