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Diversity, Ecology, and Environmental Significance of Foraminifera in Al Hamama and Susah Coastal Regions, Northeastern Libya: Insights from Holocene Sediments

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Journal of Environmental Protection 2024年第1期15卷 13-25页

作者： Belkasim Khameiss Husamaldeen Zubi Kansas Geological Survey Lawrence USA department of Earth Sciences Faculty of Science University of Benghazi Benghazi Libya department of geology and Geological Engineering University of Mississippi Oxford USA department of geology Omar Al-Mukhtar University Al Bayda Libya

This research initiative, conducted along the coastal zones of Al Hamama and Susah in northeastern Libya, aimed to enhance our understanding of Holocene benthic foraminifera assemblages and the paleoenvironmental parameters in the region. We meticulously gathered five sediment samples to analyze the composition of foraminifera populations within the unconsolidated sedimentary deposits adjacent to these locations. We successfully identified nine distinct benthic foraminifera species, including Amphistegina lobifera, Eliphidium crispum, Sigmoilinita tenuis, Sorites orbiculus, Stomatorbina concentrica, Peneroplis planatus, Pseudotriloculina rotunda, Pyrgoella sphaera, and Triloculina schreberiana. Notably, Eliphidium crispum and Amphistegina lobifera emerged as the most prevalent species. These foraminifera species exhibited distinct ecological preferences, shedding light on paleoenvironmental conditions and climatic fluctuations during the Quaternary Period in the Susah and Al Hamama coastal regions. The presence of Orbulina universa, a planktonic foraminifera species, further enriched our understanding of the paleoenvironment by providing insights into specific water depths and temperature ranges. This research significantly contributes to paleoceanography and environmental reconstruction, highlighting the invaluable use of foraminifera as proxies for exploring past environmental changes. Additionally, the study investigated the impacts of anthropogenic influences on benthic ecosystems in the Al Hamama and Susah coastal areas. These influences included reworked foraminifera specimens and the effects of karst formations, acid rain, and eutrophication. Notably, human-induced factors have visibly affected biogenic fauna and ecosystem dynamics in the study area. Consequently, this research provides valuable insights into paleoenvironmental conditions and ecological dynamics within the Susah and Al Hamama coastal regions, emphasizing the crucial role of foraminifera in re

关键词： Al Hamama Susah Northeastern Libya Holocene Sediments

早寒武纪清江丝菌牵出硫酸盐还原菌与地球环境协同演化历史

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Science Bulletin 2024年第10期69卷 1486-1494页

作者：崔琳浩朱珂磊李瑞云常超吴来源刘伟傅东静刘沛余邱浩唐国强李秋立 Robert R.Gaines 陶昕王寅李金华张兴亮 State Key Laboratory of Continental Dynamics Shaanxi Key Laboratory of Early Life and EnvironmentsDepartment of GeologyNorthwest UniversityXi’an 710069China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China department of geology Pomona CollegeClaremont CA 91711USA State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China

Sulfate reduction is an essential metabolism that maintains biogeochemical cycles in marine and terrestrial *** reducers are exclusively prokaryotic,phylogenetically diverse,and may have evolved early in Earth’s ***,their origin is elusive and unequivocal fossils are *** we report a new microfossil,Qingjiangonema cambria,from518-million-year-old black shales that yield the Qingjiang *** is a long filamentous form comprising hundreds of cells filled by equimorphic and equidimensional pyrite microcrystals with a light sulfur isotope *** lines of evidence indicate Qingjiangonema was a sulfate-reducing bacterium that exhibits similar patterns of cell organization to filamentous forms within the phylum Desulfobacterota,including the sulfate-reducing Desulfonema and sulfide-oxidizing cable *** analyses confirm separate,independent origins of multicellularity in Desulfonema and in cable *** clock analyses infer that the Desulfobacterota,which encompass a majority of sulfate-reducing taxa,diverged~2.41 billion years ago during the Paleoproterozoic Great Oxygenation Event,while cable bacteria diverged~0.56 billion years ago during or immediately after the Neoproterozoic Oxygenation *** together,we interpret Qingjiangonema as a multicellular sulfate-reducing microfossil and propose that cable bacteria evolved from a multicellular filamentous sulfate-reducing *** infer that the diversification of the Desulfobacterota and the origin of cable bacteria may have been responses to oxygenation events in Earth’s history.

关键词： Cambrian Qingjiangonema Sulfate-reducing bacteria Cable bacteria Qingjiang biota Black shale

Effect of alumina and silica nanocomposite based on polyacrylamide on light and heavy oil recovery in presence of formation water using micromodel

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Petroleum 2024年第2期10卷 338-353页

作者： Ashkan Maleki Behnam Sedaee Alireza Bahramian Sajjad Gharechelou Nahid Sarlak Arash Mehdizad Mohammad reza Rasaei Aliakbar Dehghan Science and Research Branch Islamic Azad University Institute of Petroleum Engineering School of Chemical Engineering University of Tehran School of geology College of Science University of Tehran department of Chemistry Lorestan University Iranian Offshore Oil Company

Increasing world request for energy has made oil extraction from reservoirs more desirable. Many novel EOR methods have been proposed and utilized for this purpose. Using nanocomposites in chemical flooding is one of these novel methods. In this study, we investigated the impact of six injection solutions on the recovery of light and heavy oil with the presence of two different brines as formation water using a homogenous glass micromodel. All of the injection solutions were based on a 40,000 ppm Na Cl synthetic seawater(SSW), one of which was additive free and the others were prepared by dispersing nanocomposite silica-based polyacrylamide(NCSP), nanocomposite alumina-based polyacrylamide(NCAP), the combination of both nanocomposites silica and alumina based on polyacrylamide(NCSAP),surfactant(CTAB) and polyacrylamide(PAM) with a concentration of 1000 ppm as additives. The Stability of nanocomposites was tested against the salinity of the brine and temperature using salinity and DSC tests which were successful. Alongside stability tests, IFT, contact angle and oil recovery measurements were made. Visual results revealed that in addition to the effect of silica and alumina nanocomposite in reducing interfacial tension and wettability alteration, control of mobility ratio caused a major improvement in sweeping efficiency and oil recovery. According to the sweeping behavior of injected fluids, it was found that the main effect of surfactant was wettability alteration, for polyacrylamide was mobility control and for nanocomposites was the reduction of interfacial tension between oil and injected fluid, which was completely analyzed and checked out. Also, NCSAP with 95.83% and 70.33% and CTAB with 84.35% and 91% have the highest light oil recoveries at 250,000 ppm and 180,000 ppm salinity, respectively which is related to the superposition effect of interactions between nanocomposites, solution and oil. Based on our results it can be concluded that the most effective me

关键词： Enhanced oil recovery Micromodel Polyacrylamide Nanocomposite Salinity Alumina and silica nanoparticles

Preliminary Palynostratigraphic Data on the Middle Albian-Lower Cenomanian of the Tarfaya Basin, Southwest Morocco

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Open Journal of geology 2024年第4期14卷 548-568页

作者： Khaoula Chafai Touria Hssaida Wafaa Maatouf Mohamed Z. Yousfi Sara Chakir Soukaina Jaydawi Hanane Khaffou department of geology Faculty of Sciences Ben M&#8217Sik University Hassan II Casablanca Morocco department of Petroleum Laboratory Office National des Hydrocarbures et des Mines Rabat Morocco department of geology Faculty of Sciences Dhar El Mahraz Sidi Mohamed Ben Abdellah University Fes Morocco department of geology Faculty of Sciences Mohammed V University Rabat Morocco

The Tarfaya-Laayoune-Boujdour basin is of great interest to oil exploration;on this aspect, there has been exploration by the Moroccan National Office of Hydrocarbons and Mining, which has shown indices of oil and/or gas recorded in most wells drilled in the Moroccan Atlantic margin. FD-1 well, object of this study, is one of these wells located in the offshore Tarfaya-Laayoune-Boujdour basin. A palynological examination of the processed samples revealed the existence of organic palynomorphs, well conserved and rich in dinoflagellate cysts. The latter are composed of worldwide marker taxa of high stratigraphic resolutions. Thus, the middle upper Albian (3408 - 3408.5 m) is determined by the presence of Cribroperidinium tensiftense, Tehamadinium coummia, Spiniferella cornuta, Chichaouadinium vestitum, Dinopterygium alatum and Litosphaeridium arundum. The upper Albian (3406.5 - 3408 m) is characterized by the FOs of marker taxa: Cyclonephelium chabaca, Cribroperidinium auctificum and Chichaouadinium vestitum. Lastly, the upper Albian-lower Cenomanian transition is defined between 3404 m and 3406.50 m, as suggested by the FOs of Chichaouadinium boydii, Dinopterygium tuberculatum, Sepispinula ancorifera, Litosphaeridium conispinum, Prolixosphaeridium conulum and Xenascus ceratioides.

关键词： Morocco Tarfaya-Laayoune-Boujdour Basin Albian-Cenomanian Transition Dinoflagellate Cysts Palynostratigraphy

Surveying organic matter， thermal maturity level， and paleo-environmental conditions by considering biomarker and stable carbon isotopic analysis

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Journal of Earth Science 2024年

作者： Meysam Hemmati Yaser Ahmadi Behzad Vaferi Ali Hosin Alibak David A.Wood DWA Energy Limited School of geology College of Science University of Tehran Petroleum Engineering department Faculty of Engineering Soran University department of Chemical Engineering Shiraz Branch Islamic Azad University Chemical and Petroleum Engineering department Ilam University

Biomarker and stable carbon isotope analyses are presented for the Garau formation of the Cretaceous age， an important source rock in western Iran， to reveal its potential as an oil-prone source rock. The C28/C29sterane ratio value range (0.72 to 0.83) of bitumen samples from the formation suggests that they were likely formed during phytoplankton blooms. Sterane， hopane， and isoprenoid/n-alkane ratios indicate that the formation’s organic matter predominantly consists of algae， and bacteria， accompanied by some reworked material derived from higher plants. Due to the predominance of anoxic conditions and the actions of sulfate-reducing bacteria， the bitumen present is enriched with sulfur compounds. The percentages of saturates， aromatics， and nitrogen-sulfur-oxygen (NSO) fractions in the bitumen samples classify them as naphthenic oils. Isotope analysis reveals that biodegradation and water-washing have reduced the concentrations of some volatile saturates and low molecular weight aromatics in the bitumen samples. These actions have resulted in distinctive δ13C values for the formation’s kerogen and bitumen fractions. The formation’s organic matter has been subjected to high-temperature thermal regimes and has entered the oil-generation window at the sampled localities， with vitrinite reflectance (%RC) varying between 0.7% and 0.75%.

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Structural Controls and Predictive Mapping of Tin, Niobium and Tantalum Mineralization Associated with the Mayo Darlé Stanniferous Granitoids;Contributions of Geostatistics

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Journal of Geoscience and Environment Protection 2024年第1期12卷 180-210页

作者： Bah-Yero Liman Ngounouno Ismaïla Mbowou Gbambié Isaac Bertrand Alpha Baster Kenfack Fokem André William Boroh Amadou Diguim Kepnamou department of Earth Sciences Faculty of Science University of Ngaoundéré Ngaoundéré Cameroon department of Mining geology School of Geology and Mining and Engineering University of Ngaoundéré Meiganga Cameroon department of Earth Sciences Faculty of Science University of Garoua Garoua Cameroon

The aim of this study of the spatial dispersion of tin, niobium and tantalum mineralization associated with the Mayo Darlé granitoids was to produce prospecting guides through predictive maps of Sn, Nb and Ta in the region. It was based on a database (in appendix) obtained after analysis of rock samples (greisens and quartz veins) collected in the field, using a portable X-ray fluorescence (XRF) spectrometer. Two approaches were used: 1) structural studies in the field using the directions of veins and fractures 2) the use of variographic maps, an essential element in geostatistics for determining directional anisotropies. A joint synthesis of the modelling results shows that tin, tantalum and niobium mineralization at Mayo Darlé is concentrated along strike intervals N315E to N320E, with mineralization also occurring along strike N35E for high-grade Sn, medium-grade Ta and low-grade Nb. In short, mineral concentrations disperse progressively in space: positively from east to west for tantalum and niobium, and inversely for tin.

关键词： Mayo Darlé Tin Niobium Tantalum Geostatistics Mapping

Electrobiocorrosion by microbes without outer-surface cytochromes

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mLife 2024年第1期3卷 110-118页

作者： Dawn E.Holmes Trevor L.Woodard Jessica A.Smith Florin Musat Derek R.Lovley department of Microbiology University of Massachusetts AmherstAmherstMassachusettsUSA department of Physical and Biological Science Western New England UniversitySpringfieldMassachusettsUSA department of Biomolecular Sciences Central Connecticut State UniversityNew BritainConnecticutUSA department of Biology Section for MicrobiologyAarhus UniversityAarhusDenmark department of Molecular Biology and Biotechnology Facuity of Biology and GeologyBabes-Bolyai UniversityCluj-NapocaRomania

Anaerobic microbial corrosion of iron-containing metals causes extensive economic *** microbes are capable of direct metal-to-microbe electron transfer(electrobiocorrosion),but the prevalence of electrobiocorrosion among diverse methanogens and acetogens is poorly understood because of a lack of tools for their genetic *** studies have suggested that respiration with 316L stainless steel as the electron donor is indicative of electrobiocorrosion,because,unlike pure Fe^(0),316L stainless steel does not abiotically generate H_(2) as an intermediary electron ***,we report that all of the methanogens(Methanosarcina vacuolata,Methanothrix soehngenii,and Methanobacterium strain IM1)and acetogens(Sporomusa ovata and Clostridium ljungdahli)evaluated respired with pure Fe^(0)as the electron donor,but only ***,***,and *** were capable of stainless steel *** electrobiocorrosive methanogens re-quired acetate as an additional energy source in order to produce methane from stainless *** of *** and *** demonstrated how acetogens can provide acetate to methanogens during *** only was Meth-anobacterium strain IM1 not capable of electrobiocorrosion,but it also did not accept electrons from Geobacter metal-lireducens,an effective electron-donating partner for direct interspecies electron transfer to all methanogens that can directly accept electrons from Fe^(0).The finding that ***,***,and *** are capable of electrobiocorrosion,despite a lack of the outer-surface c-type cytochromes previously found to be important in other electrobiocorrosive microbes,demonstrates that there are multiple microbial strategies for making electrical contact with Fe^(0).

关键词： acetogen corrosion Fe^(0) methanogen stainless steel

Vegetation changes across the Eocene-Oligocene transition:Global signals vs. regional development

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Science China Earth Sciences 2024年第9期67卷 2937-2952页

作者： Mengxiao WU Lutz KUNZMANN Shufeng LI Vasilis TEODORIDIS Zhekun ZHOU Tao SU CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences Senckenberg Natural History Collections Dresden department of Biology and Environmental Studies Faculty of EducationCharles University State Key Laboratory of Oil and Gas Reservoir geology and Exploitation Chengdu University of Technology Institute of Sedimentary geology Chengdu University of Technology

The Eocene-Oligocene transition(EOT) marked a rapid global cooling event, often considered as the beginning of the modern icehouse world. Influenced by various factors, including tectonic activity and paleogeographic settings, the terrestrial records indicate a diverse response of fauna and vegetation to this global event. We examined nine macrofossil assemblages from seven fossil localities on the southeastern margin of the Tibetan Plateau and from the mid-latitudinal Europe ranging from the latest Bartonian and Priabonian(37.71–33.9 Ma) to the Rupelian(33.9–27.82 Ma). Our aims were to trace and compare the vegetation history of both regions in the late Eocene and early Oligocene. The results show that both regions experienced changes in vegetation composition in response to climate change, characterized by a decrease in the percentages of broad-leaved evergreen elements and distinctive changes in general vegetation types. A general change in the overall vegetation type from subtropical broad-leaved evergreen forests in the late Eocene to temperate broad-leaved mixed deciduous evergreen forests, or mixed mesophytic forests, in the early Oligocene is recognized in both regions. The results indicate a clear change in leaf architecture, leaf margin states, and secondary venation types in the mid-latitudinal Europe, while the results from the southeastern margin of the Tibetan Plateau show a distinct reduction in leaf size. Our data suggest that both global and regional factors played key roles in shaping the vegetation in the two regions.

关键词： Eocene-Oligocene transition Plant fossil Paleoclimate Leaf architecture Biodiversity

Modeling of Total Dissolved Solids (TDS) and Sodium Absorption Ratio (SAR) in the Edwards-Trinity Plateau and Ogallala Aquifers in the Midland-Odessa Region Using Random Forest Regression and eXtreme Gradient Boosting

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Journal of Geoscience and Environment Protection 2024年第5期12卷 218-241页

作者： Azuka I. Udeh Osayamen J. Imarhiagbe Erepamo J. Omietimi department of Geoscience University of Texas Permian Basin Odessa Texas USA department of geology University of Pretoria Pretoria South Africa

Efficient water quality monitoring and ensuring the safety of drinking water by government agencies in areas where the resource is constantly depleted due to anthropogenic or natural factors cannot be overemphasized. The above statement holds for West Texas, Midland, and Odessa Precisely. Two machine learning regression algorithms (Random Forest and XGBoost) were employed to develop models for the prediction of total dissolved solids (TDS) and sodium absorption ratio (SAR) for efficient water quality monitoring of two vital aquifers: Edward-Trinity (plateau), and Ogallala aquifers. These two aquifers have contributed immensely to providing water for different uses ranging from domestic, agricultural, industrial, etc. The data was obtained from the Texas Water Development Board (TWDB). The XGBoost and Random Forest models used in this study gave an accurate prediction of observed data (TDS and SAR) for both the Edward-Trinity (plateau) and Ogallala aquifers with the R2 values consistently greater than 0.83. The Random Forest model gave a better prediction of TDS and SAR concentration with an average R, MAE, RMSE and MSE of 0.977, 0.015, 0.029 and 0.00, respectively. For the XGBoost, an average R, MAE, RMSE, and MSE of 0.953, 0.016, 0.037 and 0.00, respectively, were achieved. The overall performance of the models produced was impressive. From this study, we can clearly understand that Random Forest and XGBoost are appropriate for water quality prediction and monitoring in an area of high hydrocarbon activities like Midland and Odessa and West Texas at large.

关键词： Water Quality Prediction Predictive Modeling Aquifers Machine Learning Regression eXtreme Gradient Boosting