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Pleuromeia Corda is an iconic lycopod genus in the Early Triassic floras of the world. Pleuromeia fossils are very significant in stratigraphy and palaeoenvironmental interpretation and have been regarded as an important Lower Triassic index fossil. Although some recent studies show that the genus occurred in the lower part of the Middle Triassic, no definite Pleuromeia has been reported from the late Middle Triassic and the younger strata so far. In this paper, some reproductive organ fossils of Pleuromeia from the upper Middle Triassic Tongchuan Formation in Shaanxi Province (belonging to the Ordos Basin), North China, are described for the first time, belonging to the new species Pleuromeia obovata Deng nov. sp. Highly accurate dating results of tuff layers indicate that the age of the new species is between 241.06 ± 0.12 Ma and 241.558 ± 0.093 Ma, equivalent to the early Ladinian. This is the youngest species of genus Pleuromeia so far. Spatiotemporal distribution of Pleuromeia indicates that the genus first appeared in the Induan (Early Triassic) in North China, occurred widespread and flourished in both Laurasia and Gondwana during the Olenekian (late Early Triassic), declined from the Anisian (early Middle Triassic), survived in the Ladinian in North China, and may have gone extinct as early as the end of the Middle Triassic. North China may well have included the place of origination and the last habitats of this genus. [ABSTRACT FROM AUTHOR]

• Surface-modified carbon foam (SMCF) was obtained by carbothermal reaction of FeSO 4. • The carbothermal reaction greatly influences the microstructures of carbon foams. • Resulting Fe 2 O 3 particles were embedded into the honeycomb-like surface of SMCF. • High N, O and S contents are beneficial to the electrochemical performance. • The SMCF-1000 has relatively high specific capacitance and excellent cyclability. [Display omitted] This work developed novel surface-modified carbon foams (SMCFs) with high heteroatom contents and a certain amount of iron oxide particles via the carbothermal reduction reaction between iron oxide and the cyanate resin-based carbon foam. The effects of carbothermal reduction of iron oxide on microstructures and electrochemical properties of the carbon foams have been studied systematically using TG, XRD, FESEM, BET, and XPS. Results show that the carbothermal reduction greatly influences the microstructures of carbon foams when the temperature is higher than 600 °C. The generated iron oxide particles were embedded into the surface of carbon foams. With the increase of temperature, the surface became porous and rough with a certain graphitic structure. When the temperature arrives at 1000 °C, the as-prepared SMCF-1000 has a highest specific capacitance of 212.42 F g−1 at 1 A g−1, and the specific capacitance maintains 107% of the initial value after 10,000 charge-discharge cycles. In addition, the SMCF-1000 exhibits a maximum compressive strength of 2.52 MPa, which is expected to be a novel three-dimensional self-supporting electrode material. [ABSTRACT FROM AUTHOR]

Pelliales is a basal lineage of the simple thalloid liverworts. Here, we describe a simple thalloid liverwort from the Middle Jurassic Xishanyao Formation of the Turpan–Hami Basin, Xinjiang Uygur Autonomous Region in northwestern China. The thalloid fossil liverwort is described as a new species: Pellites hamiensis (Pelliaceae, Pelliales). Pellites hamiensis nov. sp. resembles the extant species of Pelliaceae in having ribbon-like segments, conspicuous costae that appear as ridges on the ventral surface, rectangular cells with thickened walls adjacent to the margin, and elongated cells in the middle part of the thallus. The occurrence of P. hamiensis nov. sp. extends the fossil records of Pellites back to the Aalenian-Bajocian or Bajocian (ca. 170 Ma) and suggests that the divergence time of the Pelliaceae is no later than the Middle Jurassic. [ABSTRACT FROM AUTHOR]

• First documentation of the Pagoda Positive Carbon Excursion (PPCE) on Upper Yangtze Platform. • Astronomical tuning of 3 sections yielded similar PPCE durations of 4.0 ± 0.3 Myr. • PPCE is coeval with regional transgression-highstand and oscillating climate. The continuous and well exposed sections of the Upper Ordovician on the Upper Yangtze Platform were surveyed and sampled for δ13C and δ18O isotope and conodont fossils. The geochem-stratigraphic work in the Pagoda Formation has resulted in the recognition of a positive δ13C excursion, the Pagoda Positive δ13C Excursion (PPCE). The PPCE is a distinctive positive excursion occurring in the Middle-Late Katian, consists of three minor excursions ranging from 1.5 ‰ to 3 ‰, which has been identified in all the study sections on the Upper Yangtze Platform. The PPCE interval ranges through the conodont Hamarodus brevirameus and Protopandeordus inscrulptus conodont zones in ascending order, which indicates that the PPCE develops in the Middle-Late Katian of the Late Ordovician, while the Guttenberg δ13C Excursion (GICE) in the Baltoscandia and America extended from the Late Sandbian to the Early Katian. Spectral analysis of high-resolution magnetic susceptibility (MS) logs for the four study sections shows consistent wavelengths of ca. 2.0, 0.5, 0.18 and 0.15 m. The outcrop depth-series were tuned using 405-kyr long-eccentricity cycles and the astronomical tuning yields the duration of 3.7 to 4.4 myr for the PPCE event in different sections. This is the first documentation of the PPCE event on the Upper Yangtze Platform according to the geochemo-bio-cyclostratigraphy evidences, being identified within all portions of this platform in South China. It revised the previous description of the positive δ13C excursion of the Pagoda Formation on the Upper Yangtze Platform. The trigger of the PPCE was also briefly discussed in this paper. [ABSTRACT FROM AUTHOR]

Oil and gas discoveries within Proterozoic-Cambrian strata and the majority of shale gas production occurs in relatively stable tectonic regions and characterised by moderate thermal maturity (R o °<°2.5%). The Sinian–Silurian gas resource located in China's Sichuan Basin is a definitely different example of a concurrent conventional and unconventional gas system within a tectonically complicated basin and sourced from overly-mature organic shales (R o °>°2.5%). The system comprises two components, namely a conventional Sinian–Cambrian dolomite-hosted gas resource and an unconventional Cambrian-Silurian shale gas deposit, both represent trillion cubic meter accumulations. The migration-accumulation type Sinian–Cambrian gas system, is a result of numerous processes, including (1) paleo-high trapping within a relatively stable tectonic setting, (2) appropriate source materials located in a paleo-rift trough, (3) large-scale dolomite grainstone reservoirs located near the paleo-high, (4) adequate gas produced from in-situ crude oil cracking, and, (5) gypsum-salt and shale cap rock preservation. The self-contained source-reservoir Cambrian–Silurian shale gas system, is localized by deepwater organic-rich shelf facies, characterized by high silicon and calcium contents. The recent discovery of these two massive gas fields in old and over-matured sedimentary strata, has effectively extended the upper maturity limit of R o over 3.0%, which may indicate the efficacy of broadening current natural gas exploration areas, thus potentially increasing global natural gas resources significantly. Furthermore, the discovery may spark interest in natural gas exploration in widely distributed old strata, thus encouraging co-development of conventional and unconventional petroleum accumulations. [ABSTRACT FROM AUTHOR]