Depositional environment and source rock potential of Cenomanian and Turonian sedimentary rocks of the Tarfaya Basin, Southwest Morocco

Detailed organic and inorganic geochemical analyses were used to assess the depositional environment and source rock potential of the Cenomanian and Turonian oil shale deposits in the Tarfaya Basin. This study is based on core samples from the Tarfaya Sondage-4 well that penetrated over 300m of Mid Cretaceous organic matter-rich deposits. A total of 242 samples were analyzed for total organic and inorganic carbon and selected samples for total sulfur and major elements as well as for organic petrology, Rock-Eval pyrolysis, Curie-Point-pyrolysis-gaschromatography-Mass-Spectrometry and molecular geochemistry of solvent extracts. Based on major elements the lower Cenomanian differs from the other intervals by higher silicate and lower carbonate contents. Moreover, the molecular geochemistry suggests anoxic bottom marine water conditions during the Cenomanian-Turonian Boundary Event (CTBE; Oceanic Anoxic Event 2: OAE2). As a proxy for the Sorg/Corg ratio, the ratio total thiophenes/total benzenes compounds was calculated from pyrolysate compositions. The results suggest that Sorg/ Corg is low in the lower Cenomanian, moderate in the upper Cenomanian, very high in the CTBE (CenomanianTuronian Boundary Event) and high in the Turonian samples. Rock-Eval data reveal that the lower Cenomanian is a moderately organic carbon-rich source rock with good potential to generate oil and gas upon thermal maturation. On the other hand, the samples from the upper Cenomanian to Turonian exhibit higher organic carbon content and can be classified as oil-prone source rocks. Based on Tmax data, all rocks are thermally immature. The microscopic investigations suggest dominance of submicroscopic organic matter in all samples and different contents of bituminite and alginite. The lower Cenomanian samples have little visible organic matter and no bituminite. The upper Cenomanian and CTBE samples are poor in bituminite and have rare visible organic matter, whereas the Turonian samples change from bituminite-fair to bituminite-rich and to higher percentages of visible organic matter towards the younger interval. These differences in the organic matter type are attributed to i) early diagenetic kerogen sulfurization and ii) the upwelling depositional environment. Moreover, kerogen sulfurization was controlled by the relationship between carbonate, iron and sulfur as well as the organic matter. Thus, the organic carbon-rich deposits can be grouped into: i) low Sorg and moderately organic matter-rich oil prone source rocks, ii) moderate Sorg and organic-carbon-rich oil prone source rocks, iii) high Sorg and organic carbon-rich oil prone source rocks and iv) very high Sorg and organic carbon-rich oil prone source rocks, the latter representing the CTBE interval. Types 2 to 4 will generate sulfur-rich petroleum upon maturation or artificial oil shale retorting. This integrated organic and inorganic approach sheds light on the various processes leading to the development of the world-class oil shales deposited through the Cenomanian to Turonian. In addition, this study shows how the changes in the depositional environment might have controlled kerogen sulfurization and organic matter preservation and structure. This detailed approach provides a better understanding on source rock development during the Cenomanian to Turonian in a global context, as many of the geochemical features were identified worldwide for deposits related to OAE2

Depositional environment and source rock potential of Cenomanian and Turonian sedimentary rocks of the Tarfaya Basin, Southwest Morocco

Detailed organic and inorganic geochemical analyses were used to assess the depositional environment and source rock potential of the Upper Albian to Turonian oil shale deposits in the Tarfaya Basin. This study is based on core samples from the Tarfaya Sondage-4 well that penetrated over 300m of Mid Cretaceous organic matter-rich deposits. A total of 242 samples were analyzed for total organic and inorganic carbon and selected samples for total sulfur and major elements as well as for organic petrology, Rock-Eval pyrolysis, Curie-Point-pyrolysis-gas-chromatography-Mass-Spectrometry and molecular geochemistry of solvent extracts. Based on major elements the Albian and Lower Cenomanian differ from the other intervals by higher silicate and lower carbonate contents. Moreover, the molecular geochemistry suggests marine anoxic bottom water conditions during the Cenomanian-Turonian boundary event (CTBE; oceanic anoxic event 2: OAE2). As a proxy for the Sorg/Corg ratio, the ratio total thiophenes/total benzenes compounds was calculated from pyrolysate compositions. The results suggest that Sorg/Corg is low in the Albian, moderate in the Cenomanian, very high in the CTBE and high in the Turonian samples.  Rock-Eval data reveal that the Albian is a moderately organic carbon-rich source rock with good potential to generate oil and gas upon thermal maturation. On the other hand, the samples from the Cenomanian to the Turonian exhibit higher organic carbon contents and can be classified as oil-prone source rocks. Based on Tmax data, all rocks are thermally immature.The microscopic investigations suggest dominance of submicroscopic organic matter in all samples and different contents of bituminite and alginite. The Albian samples have little visible organic matter and no bituminite. The Cenomanian and CTBE samples are poor in bituminite and have rare visible organic matter, whereas the Turonian samples change from bituminite-fair to bituminite-rich and to higher percentages of visible organic matter towards the younger interval. These differences in the organic matter type are attributed to 1) early diagenetic kerogen sulfurization and 2) the upwelling depositional environment. Moreover, kerogen sulfurization was controlled by the relationship between carbonate, iron and sulfur as well as the organic matter. Thus, the organic carbon-rich deposits can be grouped into: 1) low Sorg and moderately organic matter-rich oil prone source rocks, 2) moderate Sorg and organic-carbon-rich oil prone source rocks, 3) high Sorg and organic carbon-rich oil prone source rocks and 4) very high Sorg and organic carbon-rich oil prone source rocks, the latter being represented by the CTBE. Types 2 to 4 will generate sulfur-rich petroleum upon maturation or artificial oil shale retorting

Повышение эффективности статистического подхода к обработке данных контроля технологического процесса транспорта нефти

Тема научной работы выбрана согласно стратегии совместного сотрудничества РФ и КНР, в которой возрастают требования к эффективности использования нефтетранспортных предприятий. Целью данной дипломной работы является изучение котроля техгологического процесса во времени на примере транспорта жидкости, при помощи метода контрольных карт Шухарта, метод главных компонент и стандарт статистика. В данной работе был произведен расчет и рассмотрена возможность осуществления технологического контроля при мониторинге многопараметрового процесса транспорта жидкости по трубопроводу.The theme of the scientific work is selected according to the strategy of joint cooperation between the Russian Federation and the PRC, in which the requirements to the effectiveness of the use of oil transportation enterprises are increasing. The purpose of this thesis is to study the control of the technological process in time using the example of fluid transport, using the method of Shewhart control charts, the method of main components and the standard statistic. In this paper, a calculation was made and the possibility of implementing technological control in monitoring a multi-parameter fluid transport process through a pipeline was considered

How to quantify heavy mineral fertility from point‐counting data

Heavy minerals (HM) are widely used in provenance studies, for example, for reconstructing source areas and quantifying sediment budgets. Source rock mineral fertility influences the composition and concentration of HM in sediments. The resulting bias is of particular interest when interpreting single-grain data such as detrital age distributions. However, the quantification of fertility is complex and there are no robust data for most HM, which prevents the routine implementation of fertility in many studies. In this study, we test whether mineral fertility can be assessed by quantifying mineral concentrations in detrital samples through point counting and quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN). The challenge is to transform the resulting area percentage into mass percentage, which is a prerequisite for comparing those data with grain size or geochemical data. We suggest overcoming this problem by recording grain-size and shape metrics of minerals using image analysis, and applying several transformation steps. We test our method by (a) using a series of detrital grain mixtures of known density and mass, and (b) applying it to a natural sediment from the European Alps. Our results agree with existing methods developed for apatite and zircon, that is, the quantification of fertility through geochemistry (with P2O5 and Zr concentrations as proxies for apatite and zircon) and the separation of pure apatite and zircon concentrates using additional separation steps. The advantage of our method is its applicability to all HM (not only apatite and zircon) and the redundancy of additional separation steps, which might create bias

Effect of probiotic treatment on the clinical course, intestinal microbiome, and toxigenic Clostridium perfringens in dogs with acute hemorrhagic diarrhea

Introduction The impact of probiotics on dogs with acute hemorrhagic diarrhea syndrome (AHDS) has not been evaluated so far. The study aim was to assess the effect of probiotic treatment on the clinical course, intestinal microbiome, and toxigenic Clostridium perfringens in dogs with AHDS in a prospective, placebo-controlled, blinded trial. Methods Twenty-five dogs with AHDS with no signs of sepsis were randomly divided into a probiotic (PRO;Visbiome, ExeGi Pharma) and placebo group (PLAC). Treatment was administered for 21 days without antibiotics. Clinical signs were evaluated daily from day 0 to day 8. Key bacterial taxa, C. perfringens encoding NetF toxin and enterotoxin were assessed on days 0, 7, 21. Results Both groups showed a rapid clinical improvement. In PRO a significant clinical recovery was observed on day 3 (p = 0.008), while in PLAC it was observed on day 4 (p = 0.002) compared to day 0. Abundance of Blautia (p<0.001) and Faecalibacterium (p = 0.035) was significantly higher in PRO on day 7 compared to day 0, while in PLAC the abundance of Faecalibacterium was not significantly higher on any study day and Blautia (p = 0.016) was only significantly higher on day 21 compared to day 0. Abundance of C. perfringens was significantly lower on day 7 (p = 0.011) compared to day 0 in PRO but not in PLAC. Enterotoxin genes were significantly lower in PRO on day 21 (p = 0.028) compared to PLAC. Fecal samples of 57% of all dogs were positive for netF toxin genes on day 0 and the abundance was significantly lower on day 7 compared to day 0 in PRO (p = 0.016) and PLAC (p = 0.031). Conclusion The probiotic treatment was associated with an accelerated normalization of the intestinal microbiome. Dogs with aseptic AHDS showed a rapid decrease of netF toxin genes and fast clinical recovery in both groups under symptomatic treatment without antibiotics

An extended association screen in multiple sclerosis using 202 microsatellite markers targeting apoptosis-related genes does not reveal new predisposing factors

Apoptosis, the programmed death of cells, plays a distinct role in the etiopathogenesis of Multiple sclerosis (MS), a common disease of the central nervous system with complex genetic background. Yet, it is not clear whether the impact of apoptosis is due to altered apoptotic behaviour caused by variations of apoptosis-related genes. Instead, apoptosis in MS may also represent a secondary response to cellular stress during acute inflammation in the central nervous system. Here, we screened 202 apoptosis-related genes for association by genotyping 202 microsatellite markers in initially 160 MS patients and 160 controls, both divided in 4 sets of pooled DNA samples, respectively. When applying Bonferroni correction, no significant differences in allele frequencies were detected between MS patients and controls. Nevertheless, we chose 7 markers for retyping in individual DNA samples, thereby eliminating 6 markers from the list of candidates. The remaining candidate, the ERBB3 gene microsatellite, was genotyped in additional 245 MS patients and controls. No association of the ERBB3 marker with the disease was detected in these additional cohorts. In consequence, we did not find further evidence for apoptosis-related genes as predisposition factors in MS

Fenites associated with carbonatite complexes : a review

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Carbonatites and alkaline-silicate rocks are the most important sources of rare earth elements (REE) and niobium (Nb), both of which are metals imperative to technological advancement and associated with high risks of supply interruption. Cooling and crystallizing carbonatitic and alkaline melts expel multiple pulses of alkali-rich aqueous fluids which metasomatize the surrounding country rocks, forming fenites during a process called fenitization. These alkalis and volatiles are original constituents of the magma that are not recorded in the carbonatite rock, and therefore fenites should not be dismissed during the description of a carbonatite system. This paper reviews the existing literature, focusing on 17 worldwide carbonatite complexes whose attributes are used to discuss the main features and processes of fenitization. Although many attempts have been made in the literature to categorize and name fenites, it is recommended that the IUGS metamorphic nomenclature be used to describe predominant mineralogy and textures. Complexing anions greatly enhance the solubility of REE and Nb in these fenitizing fluids, mobilizing them into the surrounding country rock, and precipitating REE- and Nb-enriched micro-mineral assemblages. As such, fenites have significant potential to be used as an exploration tool to find mineralized intrusions in a similar way alteration patterns are used in other ore systems, such as porphyry copper deposits. Strong trends have been identified between the presence of more complex veining textures, mineralogy and brecciation in fenites with intermediate stage Nb-enriched and later stage REE enriched magmas. However, compiling this evidence has also highlighted large gaps in the literature relating to fenitization. These need to be addressed before fenite can be used as a comprehensive and effective exploration tool.This research has received funding from the European Union’s Horizon 2020 research and innovation programme under grant No 689909

Urban coral reefs: Degradation and resilience of hard coral assemblages in coastal cities of East and Southeast Asia

© 2018 The Author(s) Given predicted increases in urbanization in tropical and subtropical regions, understanding the processes shaping urban coral reefs may be essential for anticipating future conservation challenges. We used a case study approach to identify unifying patterns of urban coral reefs and clarify the effects of urbanization on hard coral assemblages. Data were compiled from 11 cities throughout East and Southeast Asia, with particular focus on Singapore, Jakarta, Hong Kong, and Naha (Okinawa). Our review highlights several key characteristics of urban coral reefs, including “reef compression” (a decline in bathymetric range with increasing turbidity and decreasing water clarity over time and relative to shore), dominance by domed coral growth forms and low reef complexity, variable city-specific inshore-offshore gradients, early declines in coral cover with recent fluctuating periods of acute impacts and rapid recovery, and colonization of urban infrastructure by hard corals. We present hypotheses for urban reef community dynamics and discuss potential of ecological engineering for corals in urban areas

Geogenic and anthropogenic lead isotope signatures in the urban environment of Natal (NE-Brazil)

In this study the effect of anthropogenic emissions on the lead isotopic composition of sediments from the Potengi-Jundiai river system near the fast growing city of Natal, NE-Brazil, is investigated. The lead isotope signatures of sediments from the region of Natal were measured by ICP QMS and can be discussed in terms of three different end members of lead. Two geogenic lead endmembers can be distinguished and also be spatially separated, as higher lead isotope ratios occur in the vicinity of the town of Macaiba while the lead isotope ratios decrease towards the city of Natal and the mouth of the estuary. Proterozoic rocks of different age are potential lead sources as Paleoproterozoic rocks occur in the catchment of Jundiai river and younger, Neoproterozoic rocks predominate towards the mouth of the river. The lead isotope signatures of the anthropogenically affected samples deviate from the signatures of the unaffected samples indicating the existence of a third, anthropogenic source of lead. This source represents the lead isotope signature of anthropogenic emitters like waste- and coal-combustion which is also revealed by other geochemical studies conducted in Brazil

Depositional environment and source rock potential of Cenomanian and Turonian sedimentary rocks of the Tarfaya Basin, Southwest Morocco

Detailed organic and inorganic geochemical analyses were used to assess the depositional environment and source rock potential of the Cenomanian and Turonian oil shale deposits in the Tarfaya Basin. This study is based on core samples from the Tarfaya Sondage-4 well that penetrated over 300m of Mid Cretaceous organic matter-rich deposits. A total of 242 samples were analyzed for total organic and inorganic carbon and selected samples for total sulfur and major elements as well as for organic petrology, Rock-Eval pyrolysis, Curie-Point-pyrolysis-gaschromatography-Mass-Spectrometry and molecular geochemistry of solvent extracts. Based on major elements the lower Cenomanian differs from the other intervals by higher silicate and lower carbonate contents. Moreover, the molecular geochemistry suggests anoxic bottom marine water conditions during the Cenomanian-Turonian Boundary Event (CTBE; Oceanic Anoxic Event 2: OAE2). As a proxy for the Sorg/Corg ratio, the ratio total thiophenes/total benzenes compounds was calculated from pyrolysate compositions. The results suggest that Sorg/ Corg is low in the lower Cenomanian, moderate in the upper Cenomanian, very high in the CTBE (CenomanianTuronian Boundary Event) and high in the Turonian samples. Rock-Eval data reveal that the lower Cenomanian is a moderately organic carbon-rich source rock with good potential to generate oil and gas upon thermal maturation. On the other hand, the samples from the upper Cenomanian to Turonian exhibit higher organic carbon content and can be classified as oil-prone source rocks. Based on Tmax data, all rocks are thermally immature. The microscopic investigations suggest dominance of submicroscopic organic matter in all samples and different contents of bituminite and alginite. The lower Cenomanian samples have little visible organic matter and no bituminite. The upper Cenomanian and CTBE samples are poor in bituminite and have rare visible organic matter, whereas the Turonian samples change from bituminite-fair to bituminite-rich and to higher percentages of visible organic matter towards the younger interval. These differences in the organic matter type are attributed to i) early diagenetic kerogen sulfurization and ii) the upwelling depositional environment. Moreover, kerogen sulfurization was controlled by the relationship between carbonate, iron and sulfur as well as the organic matter. Thus, the organic carbon-rich deposits can be grouped into: i) low Sorg and moderately organic matter-rich oil prone source rocks, ii) moderate Sorg and organic-carbon-rich oil prone source rocks, iii) high Sorg and organic carbon-rich oil prone source rocks and iv) very high Sorg and organic carbon-rich oil prone source rocks, the latter representing the CTBE interval. Types 2 to 4 will generate sulfur-rich petroleum upon maturation or artificial oil shale retorting. This integrated organic and inorganic approach sheds light on the various processes leading to the development of the world-class oil shales deposited through the Cenomanian to Turonian. In addition, this study shows how the changes in the depositional environment might have controlled kerogen sulfurization and organic matter preservation and structure. This detailed approach provides a better understanding on source rock development during the Cenomanian to Turonian in a global context, as many of the geochemical features were identified worldwide for deposits related to OAE2