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Abstract: In order to define the provenance change across the nonconformable boundary between the second and the third members of the Upper Cretaceous Nenjiang Formation (Campanian) in the north-central area of the Songliao Basin, two sandstone samples above (sample a-1 from the fourth member of the Nenjiang) and below (sample z-1 from the first member of the Yaojia Formation) the nonconformity were collected from core holes. U–Pb dating was performed on detrital zircons separated from the three sandstone samples. Detrital zircons from sample a-1 have dominant age populations of 100–110Ma, 190–220Ma, and ~1800Ma, and sample z-1 has dominant ages of 130–150Ma and ~350Ma. This paper demonstrates that the provenance of the fourth member of the Nenjiang Formation is significantly different from the first member of the Coniacian Yaojia Formation. The provenance above the nonconformity became much more complex and the eastern source increased significantly, while the western source sharply declined. The main source areas of the fourth member of the Nenjiang Formation are mainly the Zhangguangcai Range, the eastern Lesser Xiang'an Range and the southeast of Songliao Basin. The dominant provenance of the first member of the Yaojia Formation is the northern, the central and the southern Great Xing'an Range. According to the depositional ages and combining the latest seismic stratigraphic profiles in the Songliao Basin, the tectonic inversion of the eastern Songliao Basin began between 73Ma and 87Ma, which differs from the previous age of 73Ma. [Copyright &y& Elsevier]

Abstract: The Continental Scientific Drilling Project at the Cretaceous-age Songliao Basin is a drilling initiative under the framework of the International Continental Scientific Drilling Program, to recover a nearly complete Cretaceous terrestrial sedimentary record in the Songliao Basin, northeastern China. The recovered cores will provide unique opportunities for the geosciences community to advance the understanding of climate change in the Cretaceous greenhouse world, and provide a documentation of geological events relevant to the carbon cycle during this time period. This drilling project will address significant geological questions, such as the identification of important stratigraphic boundaries and the marine-terrestrial correlations of stratigraphy, the reasons for the biotic response to the terrestrial environmental changes, the terrestrial response to the Cretaceous oceanic anoxic events, the formation of terrestrial petroleum source rocks, and the mechanisms for the Cretaceous magnetic Normal Superchron (CNS). In the first stage of this drilling project, the SKI drilling, rock cores of 2485.89m in total length were recovered and the recovery ratio reached 96.46%. A series of drilling and coring technologies including regular, confined, directional, and sealed coring, were utilized to ensure a higher recovery ratio for the core, and will be described at the end of this paper. Well loggings were conducted right after coring. Core handling and storage were arranged in such a way that the scientific research was conducted on half of each core, whereas the other half of each core was preserved for long-term storage. The upcoming second stage, the SKII drilling, will combine with data from the existing SKI to provide complete high-resolution climate records of the terrestrial environment for the whole Cretaceous time period. [Copyright &y& Elsevier]