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New Early to Middle Triassic U–Pb ages from South China: Calibration with ammonoid biochronozones and implications for the timing of the Triassic biotic recovery
New zircon U–Pb ages are proposed for late Early and Middle Triassic volcanic ash layers from the Luolou and Baifeng formations (northwestern Guangxi, South China). These ages are based on analysesExpand
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Timing of the Early Triassic carbon cycle perturbations inferred from new U–Pb ages and ammonoid biochronozones.
Based on analyses of single, thermally annealed and chemically abraded zircons, a new high-precision U–Pb age of 251.22± 0.20 Ma is established for a volcanic ash layer within the “KashmiritesExpand
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The Early Triassic ammonoid recovery: Paleoclimatic significance of diversity gradients
Ammonoids recovered much faster than other marine shelly invertebrates after the end-Permian mass extinction. Based on a refined global data set at the basin level, we investigate theExpand
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Good Genes and Good Luck: Ammonoid Diversity and the End-Permian Mass Extinction
“Rapid” Recovery The Permian-Triassic extinction 252 million years ago was Earth's most severe biotic crisis since the Precambrian and is thought to have depressed diversity in its wake for millionsExpand
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Climatic and biotic upheavals following the end-Permian mass extinction
The recovery from the end-Permian mass extinction was slow and prolonged. A temperature reconstruction shows that further biotic crises during the recovery were associated with extreme warmth.Expand
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Smithian-Spathian boundary event: Evidence for global climatic change in the wake of the end-Permian biotic crisis
One of the most important carbon cycle perturbations following the end-Permian mass extinction event straddles the Smithian-Spathian boundary (SSB) (Olenekian, Early Triassic). This anomaly isExpand
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Mode and Rate of Growth in Ammonoids
In this chapter we discuss the mode and rate of growth in ammonoids, focusing primarily on postembryonic growth. We first discuss the general mode of growth and then describe the ontogenetic sequenceExpand
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Geochronological constraints on post-extinction recovery of the ammonoids and carbon cycle perturbations during the Early Jurassic
Abstract This paper presents the first quantitative study of the Early Jurassic recovery of ammonoids after the end-Triassic mass extinction based on detailed U–Pb ID-TIMS (isotope dilution thermalExpand
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Mature Modifications and Dimorphism in Ammonoid Cephalopods
The shell of an ammonoid is a kind of autobiography of the animal that once occupied it. Different parts of the shell tell different parts of the life history. The growth lines and the tiny intervalsExpand
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A new pistosaurid (Reptilia: Sauropterygia) from the Middle Triassic of Nevada and its implications for the origin of the plesiosaurs
ABSTRACT We describe a new pistosaurid sauropterygian, Augustasaurus hagdorni, gen. et sp. nov., from the Middle Triassic of Nevada. The specimen was collected in Muller Canyon, Augusta Mountains,Expand
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