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Permian stratigraphic sequences are widely distributed throughout Iranian, making this one of the best locations in the world to study15 this geological time interval. Nevertheless, some units lack detailed biostratigraphic characterization which is essential for16 palaeogeographic reconstructions. This preliminary study comprises a palynological assessment of a Permian stratigraphi...

[1] The Nilosyrtis Mensae region is important among dichotomy boundary fretted terrain outcrops, as it provides evidence of overprinting of ancient landscapes by a suite of glacial features, providing a composite view of the variety of midlatitude glacial modification processes that can occur during recent Martian ice ages. On the basis of a series of criteria developed for the identification o...

The RASC method for ranking and scaling of biostratigraphic events was developed by the authors and associates during the past 20 years. The purpose of ranking is to create an optimum sequence of events observed in different wells or sections subject to stratigraphic inconsistencies in the direction of the arrow of time. These inconsistencies, which result in crossovers of lines of correlation ...

A series of recent papers has called for multiple radiocarbon dates on planktic foraminifera to assess stratigraphic continuity in deep-sea sediment cores. This recommendation comes from observations of anomalous 14C dates in planktic foraminifera from the same stratigraphic level. Potential reasons include bioturbation, downslope transport, secondary calcification, carbonate dissolution, and d...

The Nanxiong Basin (Guangdong Province, China) preserves the most complete Asian stratigraphic record of the Cretaceous-Paleogene (K/Pg) boundary extinction and the subsequent Paleocene mammalian radiation. Despite extensive study, the precise placement of the K/Pg boundary in the Nanxiong Basin sequence has been controversial, and the timing of subsequent mammalian turnover is poorly constrain...

The recent proliferation of stratigraphic studies of delta 13C variation in carbonates and organic C in later Neoproterozoic and basal Cambrian successions (approximately 850-530 Ma) indicates a strong oscillating trend in the C-isotopic composition of surface seawater. Alone, this trend does not adequately characterize discrete intervals in Neoproterozoic time. However, integrated with the vec...

Vertebrate paleontologists have proposed a model for the terrestrial end-Permian event in the Karoo Basin, South Africa. The scenario envisions vegetational collapse that resulted in a phased extinction of vertebrate taxa in the uppermost Daptocephalus Assemblage Zone and overlying Lystrosaurus Assemblage Zone. These biodiversity patterns are placed into composite stratigraphic sections at key ...