Depositional environment and genesis of the Paleoproterozoic Astingbulake banded iron formations from the Quruqtagh Block, northeast Tarim Craton

•The Astingbulake BIF has a significant contribution from continental-sourced iron with minor hydrothermal source.•It is a Superior-type BIF deposited on a continental shelf slope.•The BIF deposited in suboxic to anoxic environments.•Ferruginous seawater conditions were still established in the Paleoproterozoic ocean.