Ammonoids and conodonts, being characterized by exceptionally high background rates of origination and extinction, were vulnerable to global environmental crises, which characteristically intensified background rates of extinction. Thus, it is not surprising that these taxa suffered conspicuous mass extinctions at the times of three negative Early Triassic global carbon isotopic excursions that...

Eudimorphodon ranzii was the first Triassic pterosaur to be described and several specimens have been referred to this taxon mainly based on the presence of multicuspid teeth. Since this dental feature has been observed in several other pterosaurs, the revision of some specimens assigned to Eudimorphodon shows that they represent new taxa as follows: Arcticodactylus cromptonellus (comb. nov.), ...

Unspecified DOI: 10.1111/j.1751-8369.1990.tb00382.x Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: http://doi.org/10.5167/uzh-112675 Originally published at: Mørk, Atle; Vigran, Jorunn Os; Hochuli, Peter A (1990). Geology and palynology of the Triassic succession of Bjørnøya. Polar Research, 8(2):141-163. DOI: 10.1111/j.1751-8369.1990.tb00382.x Geology and paly...

The Triassic, lasting from 252 to 201 million years (Myr) ago, was crucial in the origin of modern ecosystems. It is the seventh of the 11 geological systems or periods into which the Phanerozoic, the fossiliferous last 540 million years, of Earth history is divided. It might seem strange to select just one of these divisions of time as somehow more significant than the others. However, this wa...

BACKGROUND Ichthyosaurs were an important group of Mesozoic marine reptiles and existed from the Early Triassic to the early Late Cretaceous. Despite a great diversity in body shapes and feeding adaptations, all share greatly enlarged eyes, an elongated rostrum with numerous conical teeth, and a streamlined body. METHODOLOGY/PRINCIPAL FINDINGS Based on new material from China and the restudy ...

The measurement of isotope ratios in sedimentary rocks deposited over geological time can provide key insights to past environmental change over important intervals in the past. However, it is important to be aware that secondary alteration can overprint the original isotopic records. We demonstrate this principle using high-resolution carbon, sulfur, and oxygen isotope measurements in organic ...

The Beyşehir–Hoyran–Hadim Nappes crop out over 700 km from NW to SE. Above a regionally autochthonous Tauride carbonate platform the Beyşehir–Hoyran Nappes begin with a thrust sheet (c. 400 m) of mainly redeposited carbonates, quartzose sandstones and mudstones of Mid–Late Triassic age, interpreted as a proximal slope–base-of-slope succession. Above is a thrust sheet (c. 1 km) of Middle–Upper T...

Delayed Earth system recovery following the end-Permian mass extinction is often attributed to severe ocean anoxia. However, the extent and duration of Early Triassic anoxia remains poorly constrained. Here we use paired records of uranium concentrations ([U]) and (238)U/(235)U isotopic compositions (δ(238)U) of Upper Permian-Upper Triassic marine limestones from China and Turkey to quantify va...

Today’s trip traverses a nearly east-west swath of the southern Colorado Plateau in northeatern Arizona (Fig. 2.1), where the low and barren topography is developed in Permian and Triassic sedimentary rocks. Here, our focus is on the Lower-Middle Triassic Moenkopi Formation. In northern Arizona, east of Flagstaff, the Moenkopi section (Fig. 2.2) is a relatively thin (< 150 m thick) and almost e...