SHRIMP U–Pb ages of the detrital zircons from the Cretaceous Ullyeonsan Formation, SE Korea: A small piece for stratigraphic correlation in eastern Asia

Abstract

To constrain the maximum depositional age of the Ullyeonsan Formation in the Yeongyang Subbasin, southeast Korea, detrital zircon U–Pb age determination was conducted using high-resolution secondary ion mass spectrometry (HR-SIMS). The U–Pb populations of detrital zircons from the Ullyeonsan Formation show a broad range of ages from the Archean to early Cretaceous and diverse patterns depending on the temporal and spatial distribution of sedimentation. The difference in location-dependent age distribution indicates that sediments originated from adjacent areas and source rocks were exposed during the sedimentation period of the Ullyeonsan Formation. The youngest detrital zircon cluster of the Ullyeonsan Formation yields concordia age of 110.4 ± 2.5 Ma (n = 5, MSWD = 1.2), indicating the maximum depositional age. Therefore, the Ullyeonsan Formation began to be deposited from the Albian period, and the Yeongyang Subbasin started to form around the same time as the deposition of the Hayang Group in other subbasins of the Gyeongsang Basin (e.g., Miryang and Uiseong).