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Anachronistic facies and carbon isotopes during the end-Permian biocrisis : Evidence from the mid-Tethys (Kisejin, Iran)

Late Permian mass extinction (LPME) research has focused primarily on Tethyan sections because it is believed that these successions are more complete than those from other localities, and provide a more comprehensive record of the largest, most devastating extinction event in Earth history. The Kisejin section, a previously undocumented mid-Tethyan, Upper Permian-Lower Triassic succession located

Orbital cyclicity in sedimentary sequence and climatic indications of C-O isotopes from Lower Cretaceous in Qingxi Sag, Jiuquan Basin, NW China

Sedimentary deposits of the Lower Cretaceous Xiagou Formation form the most significant potential hydrocarbon reservoirs in the Qingxi Sag, Jiuquan Basin (NW China). Zircon U-Pb ages of the dated basalts at the top of the Xiagou Formation give an isochron age of 115.6 Ma, and the sedimentation interval of the Xiagou Formation was speculated to range from about 125/124 Ma to 115 Ma based on paleon

Geochemistry and mineralogy of the Oligo-Miocene sediments of the Valley of Lakes, Mongolia

The Valley of Lakes is approximately a 500-km elongate depression in Central Mongolia, where Eocene to Miocene continental sediments are long known for their outstanding fossil richness. The palaeontological record of this region is an exceptional witness for the evolution of mammalian communities during the Cenozoic global cooling and regional aridification. In order to precisely elucidate the cl

Stepwise onset of the Icehouse world and its impact on Oligo-Miocene Central Asian mammals

Central Asia is a key area to study the impact of Cenozoic climate cooling on continental ecosystems. One of the best places to search for rather continuous paleontological records is the Valley of Lakes in Mongolia with its outstandingly fossil-rich Oligocene and Miocene terrestrial sediments. Here, we investigate the response by mammal communities during the early stage of Earth's icehouse clima

Revised middle Triassic stratigraphy of the Swiss Prealps based on conodonts and correlation to the Briançonnais (Western Alps)

The Triassic in the “Médianes rigides” Nappe of the Swiss Prealps, belonging to the Briançonnais realm of the Western Alps, consists of a several hundred meters thick carbonate succession. At the localities Wiriehorn and Rothorn, 650 m above sequence base, the Costatoria goldfussi limestone, a remarkable coquina and widespread transgressive marker bed, yields the key conodont Sephardiella truempyi

Allometry in Anisian (Middle Triassic) segminiplanate conodonts and its implications for conodont taxonomy

Conodonts are a clade of chordates and are valuable indicator fossils for biostratigraphy. The segminiplanate (neogondolelliform) conodonts represent a major morphological group ranging from upper Carboniferous to Upper Triassic marine sediments. However, the morphological similarity of segminiplanate P 1 elements generates problems for taxonomy, especially in the Permian and Triassic clades. Thi

Dynamic anoxic ferruginous conditions during the end-Permian mass extinction and recovery

The end-Permian mass extinction, ∼252 million years ago, is notable for a complex recovery period of ∼5 Myr. Widespread euxinic (anoxic and sulfidic) oceanic conditions have been proposed as both extinction mechanism and explanation for the protracted recovery period, yet the vertical distribution of anoxia in the water column and its temporal dynamics through this time period are poorly constrain

3-D Image-Based Dosimetry in Radionuclide Therapy

Radionuclide therapy is the use of radioactive drugs for internal radiotherapy, mainly for the treatment of metastatic disease. As opposed to systemic cancer therapies in general, the use of radioactively labeled drugs results not only in a targeted therapy but also the possibility of imaging the distribution of the drug during therapy. From such images, the absorbed doses delivered to tumors and

A review of the evolution, biostratigraphy, provincialism and diversity of Middle and early Late Triassic conodonts

The taxonomy, diversity, evolutionary lineages, and stratigraphical distributions of Middle and early Late Triassic conodonts are reviewed and re-evaluated. Twenty-five genera are recognized in the Middle and early Late Triassic, including a new genus cited in open nomenclature. Of these, 24 genera are assigned to two families and seven subfamilies. The family Gondolellidae consists of the subfami

New data on the structure and age of the terminal Permian strata in the South Verkhoyansk region (northeastern Asia)

We present new data on the structure and age of the upper Permian strata in the basin of the Setorym River (tributary of the Vostochnaya Khandyga River) in the South Verkhoyansk region, represented by the Imtachan Formation and the lower part of the Nekuchan Formation. Based on the new findings of bivalve fossils from the Intomodesma costatum Zone, as well as on the study of carbon isotopes in the

Distribution of iridium and associated geochemistry across the Triassic-Jurassic boundary in sections at Kuhjoch and Kendlbach, Northern Calcareous Alps, Austria

Samples from strata spanning the Triassic-Jurassic boundary at the GSSP at Kuhjoch and at Kendlbachgraben were studied by NAA, XRF and combustion analysis to determine Ir levels and associated geochemistry. The results are compared to previously determined carbon isotope stratigraphy at these sections. Ir concentrations in the limestones of the Kössen Formation at Kuhjoch are very low (

New hybodontiform and neoselachian sharks from the Lower Triassic of Oman

Elasmobranchs are reported for the first time from Lower Triassic deposits in Oman. The well-preserved remains consist of isolated teeth, dermal denticles and fin spines, recovered from conodont residues. The low-palaeolatitude sections consist of Lopingian-Olenekian shallow and pelagic carbonates in exotics, olistoliths and breccia blocks that have been redeposited in younger allochthonous strata

Early Triassic conodonts of Jiarong, Nanpanjiang Basin, southern Guizhou Province, South China

Jiarong (Huishui County, Guizhou Province, South China) is a key locality for the study of the Early Triassic recovery after the end-Permian mass extinction. The size reduction of conodonts at the Smithian/Spathian transition was first documented in Jiarong, and it is also a locality that contributes to the documentation of the Early Triassic paleo-seawater temperatures. In the Jiarong sections, t

Molecular interactions between quinoa, the biocontrol agent Trichoderma and the pathogen Peronospora variabilis

Plants have developed complex molecular mechanisms to recognize and respond to the different microorganisms present in their surroundings. The most studied response mechanisms are plant defense responses. These defense response mechanisms share many similar components with the plant response mechanisms to beneficial microbes. Therefore, studying the defense response mechanisms against pathogens caPlants have developed complex molecular mechanisms to recognize and respond to the different microorganisms present in their surroundings. The most studied response mechanisms are plant defense responses. These defense response mechanisms share many similar components with the plant response mechanisms to beneficial microbes. Therefore, studying the defense response mechanisms against pathogens ca

Early Triassic conodonts and carbonate carbon isotope record of the Idrija-Žiri area, Slovenia

The first recovery of the conodont Hindeodus parvus from Žiri (Slovenia) a few years ago highlights this area for Early Triassic biostratigraphical study. Systematic sampling of five sections in the Idrija-Žiri area has yielded the new species Platyvillosus corniger sp. nov. and Neospathodus planus sp. nov. Based on these new species and other conodont elements collected here, nine discrete conod

Pool boiling heat transfer of n-pentane and acetone on nanostructured surfaces by electrophoretic deposition

This work aims to investigate pool boiling heat transfer enhancement by using nanostructured surfaces. Two types of nanostructured surfaces were employed, gold nanoparticle-coated surfaces and alumina nanoparticle-coated surfaces. The nanostructured surfaces were fabricated by an electrophoretic deposition technique, depositing nanoparticles in a nanofluid onto smooth copper surfaces under an elec

Ocean acidification and the Permo-Triassic mass extinction

Ocean acidification triggered by Siberian Trap volcanism was a possible kill mechanism for the Permo-Triassic Boundary mass extinction, but direct evidence for an acidification event is lacking. We present a high-resolution seawater pH record across this interval, using boron isotope data combined with a quantitative modeling approach. In the latest Permian, increased ocean alkalinity primed the E

Environmental controls on marine ecosystem recovery following mass extinctions, with an example from the Early Triassic

The recovery of marine ecosystems following a mass extinction event involves an extended interval of increasing biotic diversity and ecosystem complexity. The pace of recovery may be controlled by intrinsic ecosystem or extrinsic environmental factors. Here, we present an analysis of changes in marine conditions following the end-Permian mass extinction with the objective of evaluating the role of