Results of the U/Pb Dating of Detrital Zircons from Upper Cretaceous Deposits in the Novaya Sibir Island (New Siberian Islands, Anjou Island Group)

The U–Pb (LA-ICP-MS) dating of detrital zircons from the Upper Cretaceous Derevyannye Gory Formation in the Novaya Sibir Island revealed that tuffites and tuffaceous sandstones contain zircons widely ranging in age from Archean to Upper Cretaceous. The weighted average age of the youngest zircon population is 88 ± 1.0 Ma, which constrains the lower age limit for sedimentation of the Derevyannye Gory Formation to the Coniacian. The clastic material was transported from the southwest and south to the north and northeast. The main source areas for the Upper Cretaceous sedimentary basin in the Novaya Sibir Island were the Upper Jurassic–Neocomian terrigenous sequences of the New Siberian–Chukotka fold area, lithotectonic complexes of the South Anyui suture, as well as the northern part of the Verkhoyansk–Kolyma fold area, and post-orogenic Aptian–Albian volcanic and plutonic rocks from the Lyakhov Islands and Svyatoi Nos Cape. Triassic terrigenous rocks of the northern Verkhoyansk region could serve as additional sources of clastics. It is also possible that the clastic material was partially supplied from the western Anjou Islands as a result of erosion of the Aptian–Lower Albian volcaniclastic–siliciclastic rocks. The Late Cretaceous zircon population is related to the Late Cretaceous explosive acid volcanism in the eastern Arctic region.