This paper presents a detailed facies analysis and paleo-depth reconstruction of a latest Early Carnian platform drowning-sequence from the Anatolian terrane (Turkey, Taurus Mountains). A total of eight sedimentary microfacies zones were recorded. An open platform margin passes through a deeper shelf margin setting into a basinal environment influenced by more open-marine conditions. The analysis demonstrates an unexpected, pure carbonate depositional system through the so-called Carnian Pluvial Episode (CPE), which has previously been associated with dramatic climate changes throughout the Tethys region. One main finding, based on sedimentological and paleontological analyses, is a much later drowning of the carbonate platforms in Turkey than in other places. The termination of the Kartoz platform postdates the onset of the CPE in the western Tethys by one ammonite zone, corresponding to about 2 million years. The distinctly earlier demise of (north)western Tethyan carbonate platforms and reefs points to a diachrony of this event throughout the Tethys. The decline of carbonate productivity clearly occurs earlier at higher paleolatitudes and later in equatorial areas. Interpreting the CPE as the result of a global or at least Tethys-wide climatic event is therefore highly ambiguous. The described facies changes at Aşagiyaylabel probably mirror different coupling effects and, only minimally, the Tethyan-wide climate changes during the Carnian Pluvial Episode.

The internal orientation of fossil mass occurrences can be exploited as useful source of information about their primary depositional conditions. A series of studies, using different kinds of fossils, especially those with elongated shape (e.g., elongated gastropods), deal with their orientation and the subsequent reconstruction of the depositional conditions (e.g., paleocurrents and transport mechanisms). However, disk-shaped fossils like planispiral cephalopods or gastropods were used, up to now, with caution for interpreting paleocurrents. Moreover, most studies just deal with the topmost surface of such mass occurrences, due to the easier accessibility. Within this study, a new method for three-dimensional reconstruction of the internal structure of a fossil mass occurrence and the subsequent calculation of its spatial shell orientation is established. A 234 million-years-old (Carnian, Triassic) monospecific mass occurrence of the ammonoid Kasimlarceltites krystyni from the Taurus Mountains in Turkey, embedded in limestone, is used for this pilot study. Therefore, a 150×45×140 mm3 block of the ammonoid bearing limestone bed has been grinded to 70 slices, with a distance of 2 mm between each slice. By using a semi-automatic region growing algorithm of the 3D-visualization software Amira, ammonoids of a part of this mass occurrence were segmented and a 3D-model reconstructed. Landmarks, trigonometric and vector-based calculations were used to compute the diameters and the spatial orientation of each ammonoid. The spatial shell orientation was characterized by dip and dip-direction and aperture direction of the longitudinal axis, as well as by dip and azimuth of an imaginary sagittal-plane through each ammonoid. The exact spatial shell orientation was determined for a sample of 675 ammonoids, and their statistical orientation analyzed (i.e., NW/SE). The study combines classical orientation analysis with modern 3D-visualization techniques, and establishes a novel spatial orientation analyzing method, which can be adapted to any kind of abundant solid matter.

We describe a new ammonoid fauna from the Taurus Mountains of southern Turkey. The Carnian ammonoid fauna from As ßa giyaylabel is presented for the first time. Ammonoids were obtained from limestone to marl beds of an approximately 35-m-thick section, which presents the rare opportunity to investigate ammonoid faunas across the Lower-Upper Carnian boundary. Intense sampling near the village of As ßa giyaylabel led to the recognition of a new Lower Carnian (Julian 2) to Upper Carnian (Tuvalian 1) ammonoid fauna from the Kasimlar Formation. The genus Kasimlarceltites gen. nov. is reported for the first time from the Taurus Mountains, which represents the main faunal element and occurs as huge mass occurrence (n ≫ 1 million). Kasimlarceltites krystyni gen. et sp. nov., Klipsteinia disciformis sp. nov. and Anasirenites crassicrenulatus sp. nov. occur within the Lower Carnian Carbonate member (Units A-B) of the Kasimlar Formation from the Taurus Platform Units. Ammonoids described from the marls of the Tuvalian Marlstone member were deposited during a major, Tethyan-wide climate crisis -the so-called Carnian crisis -characterized by a demise of carbonate platforms. Based on the biostratigraphic relevance of certain ammonoid taxa described herein, the age of the analysed parts of the Kasimlar Formation is Julian 2 to Tuvalian 1. The discovery of the new ammonoid assemblages from As ßa giyaylabel substantiates the significance of Upper Triassic faunas within the Taurus Mountains and facilitates the correlation with faunal assemblages from other regions in the Tethyan Realm. The ammonoid fauna and facies indicate a general deepening from open-platform margins, over deeper shelf settings down to an open marine-influenced basinal environment. The tentative habitat for Kasimlarceltites gen. nov. is a shallow platform environment to upper mid-ramp.

The present study is the first quantitative comparison of Sarmatian mollusc assemblages from the Central and Eastern Paratethys seas. The assemblages (47,840 shells, 32 samples, 84

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