Lowermost Jurassic dinosaur ecosystem from the Bleymard Strait (southern France): sedimentology, mineralogy, palaeobotany and palaeoichnology of the Dolomitic Formation

2021 ◽  
pp. 1-17
Author(s):  
Jean-David Moreau ◽  
Vincent Trincal ◽  
Jean-François Deconinck ◽  
Marc Philippe ◽  
Benjamin Bourel
Keyword(s):  
Clay Mineral ◽  
Sea Spray ◽  
Subtropical Climate ◽  
Coastal Environments ◽  
Southern France ◽  
Plant Remains ◽  
Dry Conditions ◽  
Male Cones ◽  
Main Component ◽  
Mineral Analyses

Abstract We report the first Hettangian theropod tracksite (~200 Ma) yielding a rich accumulation of plant remains from the Bleymard Strait (southern France). It constitutes an excellent opportunity to reconstruct lowermost Jurassic ecosystems hosting dinosaurs and which are still poorly documented in this area. Two morphotypes of tridactyl tracks are distinguished. They share similarities with Grallator and Kayentapus. Plant-bearing beds yield abundant leafy axes (Pagiophyllum peregrinum), male cones (Classostrobus sp.), wood (Brachyoxylon sp.) and pollen of conifers (Classopollis classoides). Sedimentological, petrological and mineralogical analyses demonstrated that, in the Dolomitic Formation from Bleymard, the palaeoenvironment progressively evolved from (1) a shoreface to a foreshore domain; to (2) a shallow environment that is restricted or occasionally open to the sea; then to (3) an intertidal to supratidal zone. The Hettangian theropod ecosystem of the Bleymard Strait was composed of tidal flats that were periodically emerged and bordered paralic environments inhabited by a littoral conifer-dominated forest in which Cheirolepidiaceae were the main component. The paucity of the palaeobotanical assemblage, as well as the xerophytic characteristics of Pagiophyllum, show that flora from Bleymard was adapted to withstand intense sunlight and coastal environments exposed to desiccant conditions coupled with salty sea spray, and dry conditions. These features are those of a conifer-dominated flora under a tropical to subtropical climate. The flora as well as the clay mineral analyses suggest contrasting seasons (cyclically dry then humid). This study supports that theropods were abundant and particularly adapted to this type of littoral environment bordering Cheirolepidiaceae-dominated forests.

LATE Westphalian and early Stephanian sediments of the Dobrudzha Coalfield, NE Bulgaria

2007 ◽  
Vol 144 (3) ◽  
pp. 497-511 ◽  
Author(s):  
YANAKI G. TENCHOV
Keyword(s):  
Sea Level ◽  
Volcanic Activity ◽  
Alluvial Plain ◽  
Coal Field ◽  
Lacustrine Deposits ◽  
Plant Remains ◽  
Dry Conditions ◽  
High Precipitation ◽  
Main Component ◽  
Basin Margin

The Bolsovian to Cantabrian sediments in the Dobrudzha Coal Field are about 800 m thick. They were deposited in a depression bounded to the east, south and west by active synsedimentary faults. Most of the succession is coal-bearing clay- and siltstones, including occasional lacustrine deposits with fresh water faunas (molluscs and ostracods). Basin-wide sandstone intervals are associated with two periods of erosion and non-sequence. There are also localized sandstone bodies with vitrinized plant remains associated with the basin-margin faults. Conglomerates are only thin and rarely developed, and pebbles are only rarely found in the sandstones. There are only three basin-wide coals (m5 at the middle Makdonka Formation, n1 at the base of the Krupen formation and p3 in the middle Gurkovo Formation) representing times of diminished influx of clastic sediment, and thus of reduced movement along the basin-margin faults. Based on the depth of the erosive down-cutting, it is estimated that the elevation of the basin was at least 180 m above sea-level. The area surrounding the basin is supposed to be an alluvial plain covered with vegetation and swamps. The dense vegetation cover suggests periods of high precipitation, whereas dry conditions with active weathering are most probable during deposition of the Velkovo Formation. Volcanic activity occurred near to the depression, perhaps related to the boundary faults. In the stratigraphically highest part of the succession (the Kabalak Member), volcaniclastics are the main component of the detritic sediments. The basin eventually inverted to become a horst around which Permian sediments were deposited.

Terrestrial plants and marine algae from the Late Jurassic lithographic limestone of the Causse Méjean (Lozère, southern France)

2016 ◽  
Vol 187 (2) ◽  
pp. 121-127
Author(s):  
Jean-David Moreau ◽  
Louis Baret ◽  
Gérard Lafaurie ◽  
Carmela Chateau-Smith
Keyword(s):  
Late Jurassic ◽  
Marine Algae ◽  
Coastal Areas ◽  
Land Plants ◽  
Fossil Plants ◽  
Terrestrial Plants ◽  
Southern France ◽  
Lithographic Limestone ◽  
Dry Conditions ◽  
Marine Lagoon

Abstract A new Late Jurassic flora was discovered in the fossiliferous lithographic limestone of the Causse Méjean, Lozère (southern France). It consists of the first Kimmeridgian/Tithonian plants from this area. Fossil plants are represented by megaremains preserved as impressions. This flora shows a co-occurrence of terrestrial plants and marine algae. The land plants include vegetative remains ascribed to bennettitaleans (Zamites Brongniart, 1828), conifers (Brachyphyllum Brongniart, 1828), and pteridosperms (Cycadopteris Zigno, 1853). Marine algae were ascribed to dasyclads (Goniolina D’Orbigny, 1850). Lithological and palaeontological features suggest preservation in a flat, homogeneous, protected environment, perhaps a brackish or marine lagoon, influenced by both continental and marine inputs. This discovery complements the few existing reports of European Late Jurassic floras, and indicates that coastal habitats were dominated by sub-arborescent vegetation, consisting of bennettitaleans and pteridosperms, and arborescent plants, such as conifers. Both the palaeoenvironmental context and certain xerophytic features suggest that these terrestrial plants from the Causse Méjean were well adapted to the hot, dry conditions of coastal areas.

scholarly journals Updating sea spray aerosol emissions in the Community Multiscale Air Quality (CMAQ) model version 5.0.2

2015 ◽  
Vol 8 (11) ◽  
pp. 3733-3746 ◽  
Author(s):  
B. Gantt ◽  
J. T. Kelly ◽  
J. O. Bash
Keyword(s):  
Air Quality ◽  
Atmospheric Chemistry ◽  
Urban Areas ◽  
Regional Scale ◽  
Urban Pollution ◽  
Surface Concentration ◽  
Sea Spray ◽  
Coastal Environments ◽  
Modest Improvement ◽  
Southeastern Us

Abstract. Sea spray aerosols (SSAs) impact the particle mass concentration and gas-particle partitioning in coastal environments, with implications for human and ecosystem health. Model evaluations of SSA emissions have mainly focused on the global scale, but regional-scale evaluations are also important due to the localized impact of SSAs on atmospheric chemistry near the coast. In this study, SSA emissions in the Community Multiscale Air Quality (CMAQ) model were updated to enhance the fine-mode size distribution, include sea surface temperature (SST) dependency, and reduce surf-enhanced emissions. Predictions from the updated CMAQ model and those of the previous release version, CMAQv5.0.2, were evaluated using several coastal and national observational data sets in the continental US. The updated emissions generally reduced model underestimates of sodium, chloride, and nitrate surface concentrations for coastal sites in the Bay Regional Atmospheric Chemistry Experiment (BRACE) near Tampa, Florida. Including SST dependency to the SSA emission parameterization led to increased sodium concentrations in the southeastern US and decreased concentrations along parts of the Pacific coast and northeastern US. The influence of sodium on the gas-particle partitioning of nitrate resulted in higher nitrate particle concentrations in many coastal urban areas due to increased condensation of nitric acid in the updated simulations, potentially affecting the predicted nitrogen deposition in sensitive ecosystems. Application of the updated SSA emissions to the California Research at the Nexus of Air Quality and Climate Change (CalNex) study period resulted in a modest improvement in the predicted surface concentration of sodium and nitrate at several central and southern California coastal sites. This update of SSA emissions enabled a more realistic simulation of the atmospheric chemistry in coastal environments where marine air mixes with urban pollution.

On the domed structure and anisotropy of the B horizon of a solodized solonetz

Soil Research ◽  
1968 ◽  
Vol 6 (1) ◽  
pp. 149 ◽  
Author(s):  
JW Holmes ◽  
HC Stace
Keyword(s):  
Clay Minerals ◽  
Clay Mineral ◽  
Water Retention ◽  
Clay Content ◽  
Columnar Structure ◽  
Soil Morphology ◽  
Physical Chemical ◽  
Mineralogical Characteristics ◽  
Dry Conditions ◽  
Swelling And Shrinking

The domed columnar structure of the B horizon of solodized solonetz soils has been considered to be caused by the swelling and shrinking properties of sodium clays in the B horizon under seasonally wet and dry conditions. Such an observation, however, gives no explanation of how such soil morphology developed. With the intention of obtaining some information of the process by which the domed structure of the columns might be generated, some physical, chemical, and mineralogical characteristics of two domed columns were examined. Swelling, water retention, clay content, clay mineral species, and potassium content were some of the properties that varied systematically with position, both vertically and, more importantly, radially from the axes of the columns. That the domed columns are anisotropic was shown by these analyses. The domed structure of the columns appears to be generated by swelling strains caused partly by sand blocking the vertical cracks thereby causing horizontal confinement and partly by an increased ability to swell, even when unconfined, of the clay nearer to the axes of the columns. This increased swelling is associated with a greater degree of interstratification of the clay minerals nearer to the axes of the columns.

scholarly journals POLYAMIDAMINEPICHLOROHYDRIN APPLICATION FOR ECO-SAFE WATERFAST AND WATERPROOF FOOD PACKAGING PAPER PRODUCTION

2021 ◽  
Vol 15 (2) ◽  
Author(s):  
V. Osyka ◽  
N. Merezhko ◽  
L. Koptjukh ◽  
V. Komakha ◽  
S. Kniaz
Keyword(s):  
Polyvinyl Alcohol ◽  
Food Packaging ◽  
Food Products ◽  
Packaging Material ◽  
Packaging Materials ◽  
Functional Additives ◽  
Dry Conditions ◽  
Wood Composition ◽  
Packaging Paper ◽  
Main Component

The paper presents the research results on the properties of the pulp coniferous and deciduous wood composition in its original state and paper made from it, proposes a mechanism to increase the waterfast and waterproof food packaging paper by surface treatment with a composition based on polyamidepichlorohydrin with polyvinyl alcohol and urea.  The study was conducted in order to ensure an increase in the consumer properties of packaging paper, since when packaging materials encounter food products, their structure can change under the influence of moisture, steam, and gas. Polyamidaminepichlorohydrin was used as the main component of the composition for paper processing, as functional additives: polyvinyl alcohol and urea. The above-mentioned starting materials are environmentally friendly, since foreign inclusions in food packaging materials would pose a serious danger to human health and life, as well as to the brand image of the product in which they would be detected. It was proved that high waterfastness and waterproofness, as well as the necessary level of barrier, protective and operational properties of packaging material for food products cannot always be obtained by introducing a significant amount of polyamidaminepichlorohydrin, so the paper investigated the mechanism of interacting cellulose fibers of paper with polyamidaminepichlorohydrin, and also proved the possibility of its use to obtain packaging paper with a given set of properties. It was found that the consumption of up to 4–6% polyamidaminepichlorohydrin provides the main increase in the mechanical strength of packaging paper, both in wet and dry conditions. The resulting waterfast and waterproof material can be used for food packaging.

Clay-Humic Substance Composites for Removal of Pharmaceuticals from Water

2020 ◽  
Vol 850 ◽  
pp. 28-34
Author(s):  
Linda Ansone-Bērtiņa ◽  
Marta Jemeļjanova ◽  
Māris Kļaviņš ◽  
Rūta Ozola-Davidāne ◽  
Jorens Kviesis
Keyword(s):  
Composite Materials ◽  
Humic Acid ◽  
Humic Substances ◽  
Clay Mineral ◽  
Low Cost ◽  
Contaminant Removal ◽  
Humic Matter ◽  
Raised Bog ◽  
Acid Type ◽  
Main Component

Humic substances are the main component of soil organic matter and they actively interact with substances in soils, including pollutants. Humic acid-clay mineral composite materials can be considered as prospective and low-cost sorbents for contaminant removal. The aim of this study is to develop clay mineral and humic acid composite materials and to characterise their possible applications. For this research, montmorillonite, kaolinite and bentonite were saturated with three types of humic substances: technical humic acid from lignite, humic substances extracted from raised bog peat (Latvia) and technical K humate from lignite. Obtained sorbents were characterized using FTIR. The sorption was characterised according to the chosen clay mineral and humic acid type and concentration. Comparing the influence of clay minerals and humic substances on humic matter sorption, it has been found that the sorbed amount of humic substances depend on chosen humic substances and/or clay mineral. Obtained sorbents were used for sorption of chlorpromazine. Results indicate that the most perspective sorbents for chlorpromazine removal are bentonite and bentonite modified with humic acid. However, montmorillonite-humic composites also can be used for removal of chlorpromazine from water.

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