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The terrestrial upper Jurassic-Cretaceous (upper and lower)-Cenozoic stratigraphic succession developed continuously in Shandong province. There are intact and continuous terrestrial paleoecosystems dominated by dinosaurs, including five vertebrate fauna (bone fossil assemblages) beds from the bottom to top in the Cretaceous successions of Shandong Province. There are multiple vertebrate footprints (group) bearing beds in the transition period between Jurassic-Cretaceous and Early Cretaceous, and multiple large-scale dinosaur burial bone beds in Late Cretaceous. In recent years, it has also been found that extraterrestrial impact geological event may occur in the K/Pg transition over a hundred meters (siliceous pellet and gamma element anomalies, etc.). Shandong has a well-developed terrestrial Cretaceous succession with perfect information on paleoenvironment and paleoecology, which is an ideal area to explore the co-evolutionary relationship between terrestrial biota and paleoenvironment.

A well preserved terrestrial Cretaceous succession outcrops in Shandong Province. Although previous studies have conducted much work on the geochronology, subdivision of stratigraphic units, regional correlation and paleontology, high controversies remain about geochronology, subdivision of stratigraphic units and sedimentology. Here, we report a synthesized study of the Cretaceous successions and stratigraphy in Shandong based on the new results. Accordingly, reconstruction of framework of the Cretaceous stratigraphy in Shandong is summarized as, in descending order, the Mengyin Group of the Jurassic/Cretaceous transition, the Lower Cretaceous Laiyang Group, Qingshan Group, Dasheng Group and the Upper Cretaceous Wangshi Group.

The non-marine Cretaceous sequences are well developed in the relict basins, i.e. the Luxi basin in the west, and the Jiaolai basin in the east of Shandong Province. The Lower Cretaceous Santai Formation (140-136 Ma) in the Luxi basin contains aeolian dune deposits, which were formed under the control by westerly. The Cretaceous strata of the Jiaolai basin are divided into three groups: i.e. in ascending order, the Laiyang, Qingshan and Wangshi groups. New SHRIMP zircon U-Pb radiometric dating data demonstrated six Cretaceous volcanism episodes. The lower part of the Wangshi Group should be assigned to the upper Lower Cretaceous. An Ir anomaly recovered in the lower Jiaozhou Formation suggests that the Cretaceous/Palaeogene boundary would be in the interval between 537.3-537.4 m in the borehole JK1. At last the detailed information about the pre-symposium field excursion was introduced.

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Red beds are not entirely red sometimes, in which grey-green spheroids or irregular spots can be found. However, the formation mechanism of grey-green spheroids or irregular spots in red beds is not clear so far. Samples taken from well JK1 in Jiaozhou area of Jiaolai Basin displayed that the reduction spheroids have more Vanadium (V) element, less TFe 3 O 4 and Lead (Pb) element, almost the same content of other elements such as FeO and so on, comparing the red parts of the samples. The existence of organisms can explain the existence of green reductive spheres in the red beds formed under the oxidation environment.