Reply to comment by Liu and Liu on “⁴⁰Ar/³⁹Ar dating of ignimbrite from Inner Mongolia, northeastern China, indicates a post‐Middle Jurassic age for the overlying Daohugou Bed”

U-Pb zircon age for the Daohugou Biota at Ningcheng of Inner Mongolia and comments on related issues

“…They even stated that "the fossil assemblage of the Daohugou Biota is well correlated with the vertebrate assemblage of the Jehol Biota and is the earliest element of the Jehol Biota". These conclusions claimed by He et al [16,17] and Wang et al [2] not only arise the questions regarding the age of the Daohugou Biota and the related stratigraphic sequence even more complicated, but also yield serious conflicts with the field evidence and the lately acquired U-Pb zircon age in this paper. Thus they are needed to be seriously scrutinized.…”

“…Actually, a number of complete and successive sections containing the Daohugou Biota were measured and studied by Liu et al in 2004, and at the meantime, the Daohugou Biota-bearing sequence and its contact with overlying strata and a regional stratigraphic correlation were well worked out [13,14] . He et al [17] wondered why no field evidence is observed to support the direct contact relationship. In fact, in ascending order, a number of successive stratigraphic sequences consisting of the Middle Jurassic Jiulongshan and Tiaojishan Formations, the Late Jurassic Tuchengzi Formation are well exposed either in the Xiaoliangqian-Xiaoxigou of Ningcheng or in the Reshuitang and Sanshijiazi of Lingyuan [13,14] .…”

“…Recent studies have established the type lithological succession and correlation between the late Mesozoic Daohugou Biota-bearing strata and regional Tiaojishan Formation of the Middle Jurassic [13,14] . He et al [16,17] and Wang et al [2] , however, suggested that the strata in the Daohugou region are "an inversed sequence", and "the Tiaojishan Formation is covered by the rocks containing the Daohugou Biota". Furthermore, they insisted that "the rocks association hosting the Daohugou Biota and the Yixian Formation were both formed in the same volcanic-sedimentary phase, and the age of the Daohugou Biota is from Late Jurassic to Early Cretaceous other than Middle Jurassic".…”

“…In order to give the age of the Daohugou Biota, SHPIMP U-Pb zircon dating was conducted on the basis of our previous studies concerning the volcanic-sedimentary rocks succession and their regional correlation. Comments on the related issues raised by He et al [16,17] and Wang et al [2] are reviewed on the meantime.…”

“…Since discovery of the new biota (the Daohugou Biota) of late Mesozoic at Daohugou of Shantou Township in SE Ningcheng of Inner Mongolia in the early days of this century, a number of geologists and paleontologists have carried out enormous studies of the Late Mesozoic stratigraphies and paleontologies [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] . However, age of the Daohugou Biota and related strata has been a controversial issue for a long time.…”