Provenance study from petrography and geochronology of Middle Jurassic Haifanggou Formation in Xingcheng Basin, western Liaoning Province

Abstract

In recent decades, the Yanshanian movement in the Mesozoic has been a hotspot of much geological research, attracting numerous studies focusing on regional tectonics, basin evolution, and associated magmatism and volcanic activities. The Haifanggou Formation, exposed in Xingcheng Basin, which is one of intracontinental basins in western Liaoning Province, North China Craton (NCC), comprises mainly conglomerates dominated with interbedded sandstone. Although palaeontology, stratigraphy and lithofacies have been established, its mineralogical compositions and geochronology, even the provenance and implications for Yanshanian movement are still poorly discussed. Available sandstone samples provided a unique opportunity to study the genesis and further deciphered the tectonic mechanisms. The sandstone types of Haifanggou Formation are dominantly litho‐feldspathic litharenite and litharenite. Modal sandstone analysis shows that the origin and deposition mainly are due to arid to semi‐arid weathering and recycling of older rocks and magmatic arcs, eroded and transported debris from eastern NCC. Our new detrital zircon U–Pb ages exhibit that the maximum depositional ages of the Haifanggou Formation were conservatively estimated as late Middle Jurassic (165.6 ± 3.1 Ma). The detrital zircon U–Pb age spectrum of this formation is dominated by several peaks that indicate a provenance from the surrounding rocks including the basement of NCC. The sedimentation of the Haifanggou Formation is deposited under compressional tectonics as a local response of the Yanshanian movement which was related to the subduction of Palaeo‐Pacific Plate.

The making of calibration sausage exemplified by recalibrating the transcriptomic timetree of jawed vertebrates

“…None of these sites are now considered Kimmeridgian through Valanginian in age. The oldest ones that have yielded purported caudates [PN] (references in Skutschas, 2015, beginning with Gao and Shubin, 2003, the reference cited for this calibration by Irisarri et al, 2017) belong to the Daohugou Beds, which correlate with the Haifanggou Fm and are Callovian (late Middle Jurassic) or earliest Oxfordian (Late Jurassic) in age (Gao and Shubin, 2012; Jiang et al, 2015; Liang et al, 2019; and references therein), not Bathonian as often claimed in older literature. These lithostratigraphic units immediately underlie the abovementioned (see node 151) Lanqi and Tiaojishan formations, which have – including in the abovementioned Daxishan or Daxigou site – likewise yielded purported caudates (Gao and Shubin, 2012; Jia and Gao, 2016, 2019), and the phylogenetic analysis by Jia and Gao (2019) found the former on the hynobiid stem and the latter as a stem-pancryptobranchan.…”

“…(The value of 275 Ma suggested by Marjanović andLaurin, 2007 and2013b, is outdated. ) This is a provisional file, not the final typeset article The divergence between the salamander clades Pancryptobrancha (the smallest total group containing the crown group Cryptobranchidae: Vasilyan et al, 2013) (Gao and Shubin, 2012;Jiang et al, 2015;Liang et al, 2019;Rong et al, accepted; and references therein), not Bathonian as often claimed in older literature. These lithostratigraphic units immediately underlie the abovementioned (see node 151) Lanqi and Tiaojishan formations, which have -including in the abovementioned Daxishan or Daxigou sitelikewise yielded purported caudates (Gao and Shubin, 2012;Gao, 2016, 2019).…”

Identification and Geological Significance of Early Jurassic Adakitic Volcanic Rocks in Xintaimen Area, Western Liaoning

“…The Western Liaoning is located in the northern margin of the NCC and the eastern part of the Yanshan tectonic belt which developed a large number of Mesozoic volcanic-sedimentary basins with lots of lacustrine paleontological fossils. Therefore, Western Liaoning is one of the classic areas to study the Mesozoic tectonicmagma and biological evolution in the NCC (Figures 1 and 2) [6,18,[20][21][22][23][24][25][26]. [13]; NCC for North China Craton, SCC for South China Craton).…”