Rock magnetic records of the Qingshankou Formation of SK-1 south borehole in Songliao Basin, Northeast China, and their paleoclimate implications

► Magnetic signals of the K2qn Fm. of SK-1s mainly lie on detrital magnetite inputs. ► Magnetic signals of the K2qn Fm. recorded ancient lake-level changes. ► Magnetic signals of K2qn1 revealed the two most anoxic periods during the LAE1.