Abstract The Pingyi Basin is a late Mesozoic to Cenozoic fault basin in East China, containing a good record of Cretaceous to Paleogene non-marine carbonate and gypsum deposits. Abundant microfossils including gastropods, ostracods, charophytes and palynomorphs have been reported from this basin. A taxonomic study of ostracods from the Gejiazhuang section in the Pingyi Basin reveals a total of 17 species assigned to 11 genera. A further ostracod biostratigraphic correlation suggests the K/Pg boundary lies within Member 1 of the Bianqiao Formation in the Gejiazhuang section, which is supported by charophyte biostratigraphy.

Abstract Starting in the early 1950s, palaeontologists began to discover a wide range of Cretaceous terrestrial fossils in the Laiyang, Qingshan and Wangshi groups of the Jiaolai Basin, which resides in the eastern part of the Shandong Peninsula of northern China. Significant specimens from these deposits include various dinosaur eggs, footprints and fossils, including hadrosauroids, tyrannosaurids and ankylosaurids. These expanded the understanding of evolution, biodiversity and palaeoecology in East Asia. While many examples of the Jehol Biota from this area are not well constrained in terms of their stratigraphy and geochronology, previous studies have generally suggested that fossils from this region represent the second or third phase of Jehol Biota development. This paper reviews fossils, stratigraphic correlations, tectonic history and age estimates for the less well-studied outcrops of the Shandong Peninsula that host the Jehol Biota. We report three new 40 Ar/ 39 Ar ages for the Qingshang Group and discuss how these somewhat imprecise ages still constrain chronostratigraphic interpretation for the fossil-rich units.