scholarly journals Contribution to the sedimentology of the Messinian carbonates of the Chelif Basin (Boukadir, Algeria)

2021 ◽  
Vol 24 (1-2) ◽  
pp. 85-104
Author(s):  
Meriem L. MOULANA ◽  
Aurélia HUBERT-FERRARI ◽  
Mostefa GUENDOUZ ◽  
Meriam EL OUAHABI ◽  
Abdelhak BOUTALEB ◽  
...  
Keyword(s):  
Biogenic Elements ◽  
Petrographic Analysis ◽  
High Porosity ◽  
Carbonate Platforms ◽  
Fair Weather ◽  
The South ◽  
Minimum Thickness ◽  
High Productivity ◽  
Homoclinal Ramp ◽  
Very High

The Messinian (Upper Miocene) is characterized at the level of its marginal basins by the development of numerous carbonate platforms. This study concerns the Messinian platform of the Boukadir region in the south of the Chelif Basin in Algeria. It is composed of a lower prograding rimmed platform and an upper aggradational homoclinal ramp resting upon the Tortonian–Lower Messinian Blue Marl Formation, and its thickness reaches ~280 m in the Chelif Basin. The upper red-algae unit is uniform and subhorizontal with a minimum thickness of 90 m. Petrographic analysis of the upper ramp reveals three different microfacies, characterized by Lithothamnium, foraminifera, high porosity, and a microsparitic matrix. MF1 is a packstone, MF2 a packstone/bindstone deposited above the fair-weather wave base and MF3 is a wackestone to packstone deposited below this level. The upper unit is made up entirely of autochthonous biogenic elements without significant external fluvial contribution. It was formed in a shallow marine environment, with very high productivity and a significant export of the sediments produced. This aggradation was followed by a rapid exhumation (regression) transforming all the aragonite into calcite. The platforms correspond to the T2 complex reef formation (6.7–5.95 Ma) documented on the other Messinian carbonate platforms in the South of the Alboran Sea that formed just before the Messinian Salinity Crisis.

Yavi-Chicha and the Inka expansion: a petrographic approach

Antiquity ◽  
2014 ◽  
Vol 88 (342) ◽  
pp. 1261-1274 ◽  
Author(s):  
María Beatriz Cremonte
Keyword(s):  
Material Culture ◽  
Everyday Life ◽  
Central Andes ◽  
Archaeological Sites ◽  
Petrographic Analysis ◽  
The South ◽  
Local Identities ◽  
South Central ◽  
Production Processes ◽  
The Social

The social complexities underlying imperial control are manifest in the material culture of everyday life encountered at archaeological sites. The Yavi-Chicha pottery style of the south-central Andes illustrates how local identities continued to be expressed in practices of pottery manufacture during the process of Inka expansion. The Yavi-Chicha style itself masks a number of distinct production processes that can be traced through petrographic analysis and that relate to the different communities by whom it was produced and consumed. The dispersion of pottery fabric types in this region may partly be attributable to the Inka practice of mitmaqkuna, the displacement and relocation of entire subject populations.

West Africa Lacustrine Pre-Salt Carbonates: How Interaction of Tectonics and Diagenesis Produced Different Reservoir Facies

2016 ◽  
Author(s):  
Paola Ronchi ◽  
Giovanni Gattolin ◽  
Alfredo Frixa ◽  
Chiara Margliulo
Keyword(s):  
Congo Basin ◽  
High Porosity ◽  
Carbonate Platforms ◽  
Pore System ◽  
Reservoir Properties ◽  
Deep Faults ◽  
Facies Associations ◽  
Porosity And Permeability ◽  
Hydrothermal Dolomite ◽  
Reservoir Facies

ABSTRACT During the Early Cretaceous South-Atlantic opening, in large lacustrine basins a series of shallow water carbonate platforms grew along lake margins and paleo-highs. These carbonates are giant reservoirs in the Brasil offshore, while in Angola are productive in Cabinda (Lower Congo Basin) and are being explored in the Kwanza Basin with minor success. These carbonates have peculiar facies associations represented mainly by microbialites and coquinas, and are affected by dolomitization which modified the original pore system in different ways. In presence of deep-seated extensional faults, bounding the paleo-highs, the hydrothermal dolomitization affected the reservoir carbonate improving its quality; in fact the hydrothermal dolomite produced the so-called zebra dolomite which is characterized by high porosity and permeability. On the other hand, when there is a limited influx of hydrothermal fluid, some dolomitization is observed, but it did not produce the zebra facies and the poro-perm system has lower quality. These two examples suggest that the understanding of the distribution of deep faults may help in the prediction of the diagenetic effects and resulting reservoir properties.

Comparative between different Natural Sources of Activated Carbon for the Removal Reactive Green Dye from Aqueous Solution

2021 ◽  
Vol 19 (7) ◽  
pp. 156-164
Author(s):  
Ennas Abdul Hussein ◽  
Asraa H. Aljbory ◽  
Sadiq J. Baqir ◽  
Ameera Hassan Hamed ◽  
Azal Shakir Waheeb ◽  
...  
Keyword(s):  
Activated Carbon ◽  
High Efficiency ◽  
Nigella Sativa ◽  
Adsorption Kinetic ◽  
High Porosity ◽  
Flower Bud ◽  
Natural Sources ◽  
Freundlich Isotherms ◽  
Kinetic Result ◽  
Very High

Water pollution is one of the biggest problems facing us, so it requires the need to develop a very high-efficiency and inexpensive absorbent material from natural surfaces and compare it with expensive commercial sorbents. Where in this study an absorbent substance was prepared from the natural surfaces of Syzgium Aromaticum Flower Bud (SAFB), Nigella Sativa (NS) Converted to activated carbon to activated carbon Activated (SAFB), and Activated (NS), as these surfaces are characterized by high porosity, cheap price and very high efficiency in removing dye. The composite was illustrated via different analysis apparatus included FTIR, and FE-SEM, The adsorption result were fitted with Freundlich isotherms. The experimental kinetic result at different primary reactive green dye concentrations, were also analyzed through first model, second model and Elovich model. The obtained data appear that the model pseudo-first model fits the adsorption kinetic result through R2 0.96028, R2 0.9486, R2 0.9016 and R2 0.9620 of SAFB and ACTIVE-SAFB and Nigella Sativa (NS) and Activated (NS) in the same order.

scholarly journals Comets and the Origin of Life: Structure of Comets Nuclei and Dust

2004 ◽  
Vol 213 ◽  
pp. 271-274
Author(s):  
A. Chantal Levasseur-Regourd ◽  
Emmanuel Desvoivres
Keyword(s):  
Light Scattering ◽  
Origin Of Life ◽  
High Porosity ◽  
Laboratory Measurements ◽  
Atmospheric Entry ◽  
The Origin Of Life ◽  
Life Structure ◽  
Very High

From observations of fragmentation events, clues to a gravitational aggregates structure of some comets nuclei are given. From in-situ and remote light scattering observations, a very high porosity is estimated for dust in comae. These results suggest a possible survival of cometary organics during atmospheric entry at the epoch of intense bombardment. In the coming years, new missions to comets and laboratory measurements on the ISS, will be used to assess such a scenario.

scholarly journals The Distribution and Origin of Carbonate Cements in Deep-Buried Sandstones in the Central Junggar Basin, Northwest China

Geofluids ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Wang Furong ◽  
He Sheng ◽  
Hou Yuguang ◽  
Dong Tian ◽  
He Zhiliang
Keyword(s):  
Fluid Pressure ◽  
Junggar Basin ◽  
Isotopic Analysis ◽  
Northwest China ◽  
Petrographic Analysis ◽  
Burial Depth ◽  
Depth Range ◽  
High Porosity ◽  
Carbonate Cements ◽  
And Migration

Extremely high porosities and permeabilities are commonly discovered in the sandstones of the Xishanyao Formation in the central Junggar Basin with the burial depth greater than 5500 m, from which hydrocarbons are currently being produced. High content of carbonate cements (up to 20%) is also observed in a similar depth range. Our study aimed to improve our understanding on the origin of carbonate cements in the Xishanyao Formation, in order to provide insights into the existence of high porosity sandstones at greater depths. Integrated analyses including petrographic analysis, isotopic analysis, fluid-inclusion, and core analysis were applied to investigate the distribution and origin of carbonate cements and the influence of high fluid pressure on reservoir quality. Textural evidences demonstrate that there are two generations of carbonate cements, precipitated at the temperature of 90°C and 120°C, respectively. The carbonate cements with low δCPDB13 ranging from −19.07 to -8.95‰ dominantly occurred near the overpressure surface and especially accumulated at approximately 100 m below the surface. Our interpretation is that high content of carbonate cements is significantly influenced by early carbonate cements dissolution and migration under overpressure. Dissolution of plagioclase resulted in the development of internal pores and porosities of as much as 10% at 6500 m depth presumably.

The neck flattening defensive behaviour in snakes: First record of hooding in the South American colubrid genus Philodryas

2015 ◽  
Vol 65 (1) ◽  
pp. 73-79 ◽  
Author(s):  
Manuel Jara ◽  
Daniel Pincheira-Donoso
Keyword(s):  
Animal Species ◽  
First Record ◽  
Physical Contact ◽  
South American ◽  
Field Observations ◽  
Defensive Behaviour ◽  
Fitness Costs ◽  
Lateral Expansion ◽  
The South ◽  
Very High

Animal species have evolved a remarkable diversity of defensive phenotypic strategies aimed to deceive predators and other forms of danger. By relying on deception, these adaptations increase the chances of avoiding physical contact that may otherwise have very high fitness costs. One such deceptive behaviour is the popularly-known neck flattening, or “hooding”, observed in some snakes. Hooding consists in the lateral expansion and dorso-ventral flattening of the neck, which creates the impression of a bigger opponent during confrontations. This trait is highly characteristic of cobras (Elapidae family). However, neck flattening is not exclusive to elapids, and has in fact been observed in a few other snake lineages, including some species of the families Lamprophiidae and Colubridae. Here, we present the first report of hooding behaviour in the South American colubrid genus Philodryas, based on field observations conducted on the Chilean species P. chamissonis (the long-tailed snake). Our report adds to the few cases in which this deceptive behaviour has been observed in snakes outside the cobra family.

GEOLOGY OF BARROW ISLAND OIL FIELD

1973 ◽  
Vol 13 (1) ◽  
pp. 49 ◽  
Author(s):  
Keith Crank
Keyword(s):  
Oil And Gas ◽  
Water Injection ◽  
Water Source ◽  
Upper Jurassic ◽  
Oil Field ◽  
Late Triassic ◽  
Low Permeability ◽  
High Porosity ◽  
The South ◽  
The North

The Barrow Island oil field, which was discovered by the drilling of Barrow 1 in 1964, was declared commercial in 1966. Since then 520 wells have been drilled in the development of this field which has resulted in 309 Windalia Sand oil producers (from about 2200 feet), eight Muderong Greensand oil wells (2800 feet), five Neocomian/Upper Jurassic gas and oil producers (6200 to 6700 feet), eight Barrow Group water source wells and 157 water injection wells.Production averages 41,200 barrels of oil per day, and 98% of this comes from the shallow Windalia Sand Member of Cretaceous (Aptian to Albian) age. These reserves are contained in a broad north-plunging nose truncated to the south by a major down-to-the-south fault. The anticline is thought to have been formed initially from a basement uplift during Late Triassic to Early Jurassic time. Subsequent periods of deposition, uplift and erosion have continued into the Tertiary and modified the structure to its present form. The known sedimentary section on Barrow Island ranges from Late Jurassic to Miocene.The Neocomian/Jurassic accumulations are small and irregular and are not thought to be commercial in themselves. The Muderong Greensand pool is also a limited, low permeability reservoir. Migration of hydrocarbons is thought to have occurred mainly in the Tertiary as major arching did not take place until very late in the Cretaceous or early in the Palaeocene.The Windalia Sand reservoir is a high porosity, low permeability sand which is found only on Barrow Island. One of the most unusual features of this reservoir is the presence of a perched gas cap. Apparently the entire sand was originally saturated with oil, and gas subsequently moved upstructure from the north, displacing it. This movement was probably obstructed by randomly-located permeability barriers.

scholarly journals Hygrothermal Behavior of Clay - Sunflower (Helianthus annuus) and Rape Straw (Brassica napus) Plaster Bio-Composites for Building Insulation

2017 ◽  
Vol 21 ◽  
pp. 242-248 ◽  
Author(s):  
Yoann Brouard ◽  
Naima Belayachi ◽  
Dashnor Hoxha ◽  
Stéphane Méo ◽  
Wajih Abdallah
Keyword(s):  
Hydraulic Properties ◽  
Clay Soil ◽  
High Porosity ◽  
Low Carbon ◽  
Indoor Climate ◽  
Rape Straw ◽  
Building Insulation ◽  
Hygrothermal Behavior ◽  
The Impact ◽  
Very High

The aim of this experimental investigation is to study and compare hygrothermal properties of different materials based on vegetable aggregates and clay in order to prove the performance of the developed composite in the framework of BIOCOMP project. Crude earth is known to have very high capacities to regulate indoor humidity. Vegetable aggregate is characterized by high porosity leading also to very effective natural indoor climate regulators. Then, we expect the mix of these two material will to produce an insulation bio-composite with enhanced thermal and hygroscopic performance. Sunflower stem, rape straw and clay used in this investigation are considered as a very low carbon footprint because they are real local agricultural byproducts. Clay-sunflower and rape bio-composites seem to be appropriate and effective biobased insulating plasters, further investigations must be performed in order to characterize more accurately their interesting hygrothermal properties as long as the acoustical and mechanical aspects. Samples have been manufactured with four different vegetable aggregates (rape straw, sunflower bark, sunflower pith and a mix of sunflower pith and bark) at a same binder/aggregate ratio. The same clay soil is used as a binder for the four bio-composites. The thermal properties for the different bio-composites were obtained from the thermal conductivity measurements after various relative humidity, in order to evaluate the impact of the water content on the thermal parameters. For the hydraulic properties, the sorption-desorption isotherms for the four composites are obtained. The results show a significant effect of the different aggregates on the hygrothermal behavior of the bio-composite based on clay.

Natural mixture of silica and smectite as a new clayey material for industrial applications

Clay Minerals ◽  
2009 ◽  
Vol 44 (4) ◽  
pp. 525-537 ◽  
Author(s):  
U. Sohling ◽  
F. Ruf ◽  
K. Schurz ◽  
K. Emmerich ◽  
A. Steudel ◽  
...  
Keyword(s):  
Protein Separation ◽  
Amorphous Material ◽  
Chemical Properties ◽  
Industrial Applications ◽  
High Porosity ◽  
Clayey Material ◽  
Physico Chemical ◽  
Natural Mixture ◽  
Biodiesel Purification ◽  
Very High

AbstractThe main physico-chemical properties of a new smectitic clay containing large amounts of amorphous material are reviewed and potential industrial applications of this type of clay are discussed. Due to a 34% amorphous material content (natural silica gel), the investigated clay has very high porosity and can be used as it is or in acid-impregnated form for oil bleaching or phosphate reduction in edible oil. In the field of biodiesel purification, the new clay can be used to remove, in particular, mono-, diglycerides and glycerol. The natural silica-smectite mixture is also suitable as a carrier for liquid ingredients, for example in animal feeds, and might serve as a partial or complete substitute for synthetic precipitated silicas. In the field of bioseparation processes, the clay can be used as an adsorbent for protein separation by means of cation exchange. Due to the suppressed swelling (compared with smectite alone), it can be packed in columns which can be regenerated.

Sign in / Sign up

Export Citation Format

Share Document