The Global Stratotype Section and Point (GSSP) of the Silurian/Devonian boundary, Lower Devonian Series Lochkovian Stage was formally placed in 1977 at Klonk, Czech Republic, first appearance graptolite Uncinatograptus uniformis (Přibyl). However, since then, correlation this limit has been often hampered carbonate facies where graptolites are uncommon or totally absent. A large calcareous depo...

A long-term goal of vertebrate biostratigraphers is to construct a microvertebrate biostratigraphy for lower Mesozoic rocks that complements and extends the mammal-based biostratigraphy in place for Upper Cretaceous-Recent deposits. Here we report substantial progress toward achieving this goal based on the distribution of microvertebrate fossils in the Upper Triassic Chinle Group of the wester...

The late Smithian extinction represents a major event within the Early Triassic. This generally corresponds to succession of two, possibly three successively less diverse, cosmopolitan ammonoid assemblages, which when present, provide robust biostratigraphic framework and precise correlations at different spatial scales. In western USA basin, known occurrences latest taxa are rare until now, ha...

The Bighorn Basin of northwestern Wyoming preserves one of the most complete records of middle Paleocene to lower Eocene continental biota. The geochronology of this important interval depends partly on numerical calibration of the geomagnetic polarity time scale (GPTS), but the middle and late Paleocene parts of the GPTS have been poorly constrained radioisotopically. A new volcanic ash from t...

The stratigraphic and paleoecologic investigations of the Middle Triassic Kádárta section western part Transdanubian Range (Hungary) let an insight to drowning isolated carbonate platform deposition following pelagic successions in deep neritic bathyal environment. biostratigraphic radiometric ages revealed presence a gap between Pelsonian (Middle Anisian) shallow-marine carbonates overlying de...

Abstract Palynofacies is based on the different types of dispersed/sedimentary organic matter (DOM/SOM) and has been used as a proficient proxy for palaeoclimatic reconstructions in sedimentary deposits various time spans. It also acknowledged an effective tool domains like sequence biostratigraphy, palyno-biostratigraphy, palaeodepositional history, identification depositional processes, oxic–...

We have used palaeomagnetic methods to constrain an age model for the 624.15 m succession of Oligocene-Miocene glaciomarine sediments recovered from the CRP-2/2A drillcore, McMurdo Sound, Antarctica. Identification of characteristic remanent magnetization (ChRM) directions on vector component plots demonstrates that secondary overprints have been successfully removed by stepwise alternating fie...

Thick, unmetamorphosed successions of siliciclastic and carbonate rocks in eastern and western Siberia preserve a record of Middle Riphean to Early Upper Riphean sedimentary environments and geochemistry. Consistent with data from other continents, our studies in the Uchur–Maya region in southeastern Siberia and the Turukhansk Uplift in northwestern Siberia suggest a first-order shift in C from...