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In this study, the effect of different sizes and weights of active carbon as a remediator was evaluated on reduction or removal of petroleum hydrocarbons of a soil polluted by petroleum sludge. The present pilot study was conducted as a split plot in time experiment based on a completely randomized design with three replicates under laboratory conditions for period of 60 days. The experimental treatments included active carbon weights and sizes of 100 g and 0.3 mm (W100S0.3), 100 g and 1.5 mm (W100S1.5), 100 g and 4 mm (W100S4), 150 g and 0.3 mm (W150S0.3), 150 g and 1.5 mm (W150S1.5), 150 g and 4 mm (W150S4) and control (C). Total petroleum hydrocarbon (TPH) and microbial respiration were measured each ten days. The results showed that concentration of TPH decreased with increasing active carbon weight and size. The highest and lowest TPH concentration at all 10-day intervals was associated with control and W150S0.3 treatments. Decreased TPH was accompanied by increased microbial respiration. In general, TPH biodegradation constant (K) increased and half-life times (T1/2) decreased by increasing active carbon application with smaller sizes. The lowest value for TPH biodegradation percentage was associated with W100S4 and W100S1.5 treatments. Active carbon treatments of W150S0.3 and W150S1.5 led the best TPH biodegradation in petroleum sludge-polluted soil. Therefore, active carbon remediator may be applied as a low-cost, efficient and environment-friendly strategy for remediation of petroleum pollution in soil. [ABSTRACT FROM AUTHOR]

The hypersaline Dead Sea and its sediments are natural laboratories for studying extremophile microorganism habitat response to environmental change. In modern times, increased freshwater runoff to the lake surface waters resulted in stratification and dilution of the upper water column followed by microbial blooms. However, whether these events facilitated a microbial response in the deep lake and sediments is obscure. Here we investigate archived evidence of microbial processes and changing regional hydroclimate conditions by reconstructing deep Dead Sea chemical compositions from pore fluid major ion concentration and stable S, O, and C isotopes, together with lipid biomarkers preserved in the hypersaline deep Dead Sea ICDP‐drilled core sediments dating to the early Holocene (ca. 10,000 years BP). Following a significant negative lake water balance resulting in salt layer deposits at the start of the Holocene, there was a general period of positive net water balance at 9500–8300 years BP. The pore fluid isotopic composition of sulfate exhibit evidence of intensified microbial sulfate reduction, where both δ34S and δ18O of sulfate show a sharp increase from estimated base values of 15.0‰ and 13.9‰ to 40.2‰ and 20.4‰, respectively, and a δ34S vs. δ18O slope of 0.26. The presence of the n‐C17 alkane biomarker in the sediments suggests an increase of cyanobacteria or phytoplankton contribution to the bulk organic matter that reached the deepest parts of the Dead Sea. Although hydrologically disconnected, both the Mediterranean Sea and the Dead Sea microbial ecosystems responded to increased freshwater runoff during the early Holocene, with the former depositing the organic‐rich sapropel 1 layer due to anoxic water column conditions. In the Dead Sea prolonged positive net water balance facilitated primary production and algal blooms in the upper waters and intensified microbial sulfate reduction in the hypolimnion and/or at the sediment–brine interface. [ABSTRACT FROM AUTHOR]

Recent claims based on hydrodynamic modelling within a sequence stratigraphical perspective of incised valley fill sedimentation have argued that the Lower River Murray and its terminal lakes Alexandrina and Albert represented a marine–estuarine lake system, with marine salinities for some 200 km upstream from the Murray Mouth. These claims have encouraged proposals for the removal of barrages near the Murray Mouth to restore the 'original natural condition' of the lakes. It has also been suggested that fine-grained terrestrial sediments were trapped in this mega-lake, necessitating a re-assessment of the Holocene climatic history of southeastern Australia determined from the study of continental slope cores. We show that throughout Holocene time (the past 11.7 ka), the Lower River Murray remained a freshwater-dominated system, based on a range of mutually complementary sedimentary evidence. Radiocarbon dating of Aboriginal middens adjacent to the river and lakes comprising freshwater mussels (dominantly Velesunio ambiguous), crayfish (Euastacus armatus), turtles (Emydura macquarii) and otoliths of freshwater fish species, such as Murray cod (Maccullochella peelii), confirm freshwater riverine and lacustrine conditions throughout the Holocene. Lake Alexandrina also contains endemic obligate freshwater fishes, including a genetically divergent and locally adapted lineage of southern pygmy perch (Nannorpeca australis), revealing an evolutionary history linked to freshwater habitat in the lakes since the late Pleistocene. Freshwater diatoms from fine-grained fluvial clay successions at Riverglen Marina, and diatoms and lacustrine sediments, including sapropels in the lower lakes and their former embayments of Cooke Plains and Waltowa Swamp, also chronicle a history of freshwater deposition. Lakeshore ridges of terrestrially derived quartz sand formed during elevated freshwater lake levels 8.0 ± 1.2 ka ago, while consolidated masses of the freshwater clam Corbicula australis, radiocarbon dated at 2650 ± 90 year BP, also attest to long-term freshwater conditions. An open Murray Mouth is prima facie evidence for sustained river discharge, and the mouth remained open throughout the Holocene based on geomorphological evidence. The barrages that were built to retain freshwater within the lower lakes, in response to upstream water abstractions, which had reduced river flows, provide the closest analogue of the 'original' conditions of this environment. With increased automation, nuanced barrage operation could even better simulate the original environment, whereas removing the barrages and building a weir at Wellington would destroy the character of this internationally significant Ramsar Wetland, with detrimental impacts farther upstream. Paleoclimatic, geomorphological and modelling reconstructions, together with sedimentary records based on freshwater diatoms, molluscs, fish, turtles and lacustrine systems and evidence of genetically divergent and locally adapted obligate freshwater fishes, demonstrate that predominantly freshwater conditions were present in the Lower River Murray and its terminal lakes throughout Holocene time (11.7 ka). The empirical observations presented in this paper reveal that a large marine-dominated mid-Holocene estuary was not present in the Lower River Murray, Australia. Proposals to remove the barrages near the Murray Mouth would destroy the long-term freshwater environment of this Internationally Significant Wetland Site with negative ecological impacts. [ABSTRACT FROM AUTHOR]

The purpose of the study presented in the article is to implement modern hydrographic characteristics of freshwater of the Shatsk Lakes (28 lakes in Volyn Polissya, Ukraine) by typing water bodies according to the requirements of the EU Water Framework Directive, assessment of the chemical composition of lake water and bottom sediments (sapropel), determination of the opportunity for their recreational use in the special status of the district as a national park. Despite the presence of the two large lakes (Svityaz - 26.2 km² and Pulemetske - 15.5 km²), very small lakes with a water surface area of less than 0.5 km² (64%) are dominating in the Shatsk group. Mineralisation of calcium-hydrocarbonate lake waters is 115-303 mg⋅dm-3 and calcium-sulphate aqueous extract of sapropel is - 318-1451 mg⋅dm-3. Using a Piper diagram, it was found that there is genetic homogeneity between surface and groundwater, indicating a significant share of groundwater in the water supply of lakes. There are eight species of sapropel deposits in 19 lakes of the district. A wide range of chemical composition and physical and mechanical properties of sapropel deposits of the Shatsk Lakes allow us to consider them as an important resource for agriculture and industry. We found that sapropel from Shatsk Lakes meets the requirements for therapeutic mud and can be used for therapeutic and health purposes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sulfolane, an industrial solvent commonly used for sweetening natural gas, has recently emerged as a contaminant of concern in Alberta because of its widespread detection around many gas processing sites. In the work reported in this paper, the aerobic biodegradation of sulfolane by Pseudomonas strain or Archaea strain and mixed bacterial cultures was studied. The evaluation was furtherly conducted using Pseudomonas which had been acclimated to water contaminated with sulfolane. The impacts of co‐contaminant, initial sulfolane concentration and soil content on biodegradation of sulfolane using acclimated Pseudomonas were also investigated. RESULTS: The results showed that Pseudomonas degraded sulfolane at a rate of 2.03 mg L−1 h−1 while Archaea strain degraded sulfolane at a rate of 0.04 mg L−1 h−1. Pseudomonas and Archaea inoculated with aquifer sediments containing indigenous microbes achieved a higher sulfolane degradation rate. Acclimation of Pseudomonas to sulfolane environment sufficiently mitigated the lag period before the onset of the biodegradation process. CONCLUSIONS: Pseudomonas is a good candidate for aerobic biodegradation of sulfolane in groundwater. Aerobic biodegradation of sulfolane by Pseudomonas can be significantly enhanced through inoculation with sulfolane‐contaminated sediments or acclimatization to sulfolane environment. © 2022 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The Shales of Mianwali Formation in Surghar Range, Pakistan has been analyzed and studied geochemically to assess its hydrocarbon potential, types of organic matter and thermal maturity. Organic geochemical analyses were carried out on fifteen outcrop samples of the studied formation. Various screening techniques including TOC measurement, Rock Eval pyrolysis were used to evaluate the hydrocarbon potential, types of organic matter and thermal maturity of the studied formation. The average total organic carbon values and genetic potential (GP) are < 0.5 wt. % & < 2 kg/ton respectively, indicated that the sediments has poor source rock potential. The different cross plots including hydrogen & oxygen indices HI vs OI, HI vs Tmax and S2 vs TOC indicated that the formation is dominated by type IV kerogen. The Tmax values of analyzed samples ranges from 418 °C to 429 °C showing insufficient temperature to produce hydrocarbon at present condition. The overall high values of oxygen index (OI) and low values of hydrogen index (HI) represents the organic matter of the studied samples are poorly preserved and oxidized consisting type IV kerogen in the studied section. The source rocks geochemistry is a best tool to identify a petroleum system in an area, as multiple source rocks are present in Surghar Range and most wells are abandoned in the study area. So, this study was aimed to geochemically analyzed and study the outcrop samples of this formation, and correlate with the subsurface. [ABSTRACT FROM AUTHOR]

Over the last decade, there has been an irreversible shift from hydrocarbon exploration towards carbon storage, low-carbon energy generation and hydrogen exploration. Whilst basin modelling techniques may be used to predict the migration of hydrocarbons through sedimentary basins on geological timescales, there remains little understanding of how fluids behave at the basin scale on present-day timescales. We apply the Darcy flow equation to present an algorithm to determine the basin-scale mobilities and maximum vertical velocity, v max , of CO 2 , methane, hydrogen and hydrocarbons with depth for sandstone and carbonate. v max for CO 2 and methane are on scales of m/year, whilst values for hydrocarbon fluids are an order of magnitude smaller than for other fluids. Our results indicate that the fluid mobility of subsurface CO 2 may be sensitive to surface and near-surface temperature variations. v max for hydrogen is approximately 2–10 times greater than hydrocarbon fluids, yielding important consequences for the future use of basin modelling software for determining hydrogen migration for exploration and storage. [ABSTRACT FROM AUTHOR]

A novel technique for the in situ removal of mineral hydrocarbons from aged brownfields is described. The approach uses emulsions of plant oil (5–10%, rapeseed) in water, which were found to extract 50–85% of mineral hydrocarbons in one leaching step from the non-saturated zone. The emulsion was allowed to travel though the ground and was pumped off from the groundwater level. Approximately 15–50% of the plant oil stayed in the soil. By flushing the area with water afterwards, that amount can be reduced to 10–30%, and in some cases to <5%. This process is only suitable for sand, not for clay. It can be a good preparation for subsequent enzymatic cleavage and microbiological degradation, as part of a multi-stage in situ treatment process. Additionally, plant oil that infiltrated into the saturated zone was used to flush mineral hydrocarbons, which could be pumped off from the groundwater level. It was further tested whether the separation of mineral oil/plant oil and water can be performed by oil-absorbing, reusable non-wovens. Residual concentrations of <2% of water in oil, and 0.3–0.7 mg/L of oil in water were found. In this work, lab trials led to field trials, where more than 500 m3 of water were sent over a pilot installation for oil/water separation using non-wovens. A slightly better separation performance than by oil separators was observed. This process has the potential to be combined with a regular oil separator to allow water purification to a level at which it can be reintroduced into the ground. The technique was tested on a brownfield in Lower Austria, a former refinery site abandoned approx. 80 years ago with a peak hydrocarbon contamination of 40,000 mg/kg of dry soil and free-floating mineral oil on the groundwater level. Since in situ techniques can be more environmentally benign and less costly than traditional remediation approaches, this novel approach holds an interesting potential, which could be proven at a technology readiness level (TRL) of 5. [ABSTRACT FROM AUTHOR]

Organic-rich lacustrine shales are widely developed in China, and they have long been simply regarded as homogeneous source rocks, which restricts the understanding of intrasource oil accumulation. At present, the study of the LXF (Lower Member of the Xingouzui Formation) in the Jianghan Basin as an unconventional oil reservoir is still in its infancy, and the hydrocarbon accumulation mechanism is still unclear. Geochemical and mineralogical studies were carried out on a suite of samples from the 100-m-thick sequence, i.e., LXF II Oil Bed, by using XRD, SEM, MICP, and Rock-Eval pyrolysis. The results show that the II Oil Bed is rich in carbonate and poor in clay, so it shows a good fracturing tendency. The high degree of heterogeneity in mineral composition leads to frequent interbedding of different lithofacies. In the II Oil Bed, intercrystalline pores, interparticle pores, and intraparticle pores are developed, and micro-fractures are often observed. However, the main pore types, pore size distribution, and connectivity are quite different among lithofacies, and the carbonate-rich lithofacies have better reservoir capacity. The OM (organic matter) abundance of the II Oil Bed varies greatly and generally ranges from fair to very good. Coupled with its early-mature to mature Type II OM, it is considered to have the characteristics required for oil generation. Comprehensive analysis shows that the II Oil Bed has good shale oil exploration prospects, and the enrichment of shale oil in the sequence is the result of multiple factors matching. Firstly, high organic matter abundance is the material basis for shale oil enrichment. Secondly, thermal maturity is a prerequisite, and the difference in burial depth leads to the differential enrichment of shale oil in different areas. Thirdly, pores and micro-fractures developed in shale not only provide space for hydrocarbon storage, but also form a flow-path network. Finally, multi-scale intrasource migrations are key processes ranging from the scale of lithofacies to the intervals, which further results in the differential shale oil enrichment in different lithofacies and intervals. Considering the hydrocarbon generation capacity and reservoir quality, the prospective depth for shale oil exploration in the study area is >1350 m. The findings of this study can help in the better-understanding of the shale oil enrichment mechanism, and the optimization of future exploration strategies. [ABSTRACT FROM AUTHOR]

The Colombian Eastern Cordillera constitutes a region with potential for finding hydrocarbon reserves that are still under-explored, despite the existence of oil and tar sand production. The intense tectonic deformation affects the petroleum systems and increases exploration challenges due to the different generation, maturation, and entrapment conditions that they produce. Diverse geochemical analysis conducted on strategic samples determines that these are likely generated by the same anoxic marine source rock type. Two source rock samples we investigated are characterized by very different biomarker signals as compared to the tar sands and oil samples. Both samples are dominated by hopanes as compared to tri- and tetracyclic terpanes, with very low (Tibasosa Formation) to no (Chipaque Formation) extended tricyclic terpanes. The Soapaga Thrust, along which the analyzed samples are located, has exercised first-rate regional structural control of the distribution of hydrocarbons in the studied area. The uplift of their Mesozoic hanging wall produces intense erosion with sediment transport towards the eastern footwall forming the present infill of the Arcabuco basin. The kitchen areas were connected with the shallower entrapment sectors where excellent reservoir levels such as the Picacho Formation before the Soapaga Thrust movement. The high degree of biodegradation observed in the Picacho Fm. tar sands support early charge before the Soapaga thrust movement, and severe biodegradation following the thrust movement when hydrocarbon supply from the kitchen was interrupted. This work aims to contribute to a better understanding of the geochemical characteristics of the petroleum systems due to the action of the Soapaga Thrust. [ABSTRACT FROM AUTHOR]

In the study of oil pollution of soils, various methods of analysis are used to assess the extent and degree of damage and to predict the consequences. However, because of the considerable variability in the composition of oil and oil products from different sources and the impossibility of creating universal reference samples for calibration, the results of analyses obtained by different methods vary greatly. Discrepancies in the results may reach 200–800%. The sources of errors in the assessment of oil contamination of soils have been studied using gravimetric, chromatography–mass spectrometry, and infrared spectroscopy methods and laboratory contamination of a sample of alluvial soil with crude oil. It has been shown that less than 50% of the mass of polluting oil pass into the analytical form. Moreover, the heavy part of the oil, represented by highly polar components—resins and asphaltenes—remains generally undetermined by the existing methods, though these particular fractions require the maximum time for their destruction under natural conditions. The study of the removal of oil and oil products from the contaminated soil owing to evaporation of light hydrocarbons and bio-oxidation by strains of the aboriginal microflora under model conditions in the alluvial soil sample indicates that the total loss of the mass of introduced oil reaches 17% after a 60-day exposure at a temperature of 23°. In this case, the relative concentrations of aromatic compounds, resins, and asphaltenes increase. To obtain a real picture of oil contamination in soils and rocks, the use of the methods of organic geochemistry can be recommended. [ABSTRACT FROM AUTHOR]

Continuous exploration has triggered a heated debate on hydrocarbon resource potential in the southern slope zone of the Kuqa foreland basin, and sources of the Mesozoic-Cenozoic oil and gas have become a key problem to be solved in this region. Composition and organic geochemical parameters of crude oil and natural gas from the southern slope zone of the Kuqa foreland basin were illustrated in order to reveal their origin by using a combination of gas chromatograph (GC), gas chromatogram-mass spectrum (GC-MS) and carbon isotope analyses. The characteristics of crude oil, such as low density, viscosity, solidification point and sulfur content, and high wax content, indicate that source of the crude oil is continental. The biomarker compositions of crude oil are characterized by low to medium molecular weight compounds (n-C12 to n-C20), high Pr/Ph ratios (>1.0), low phytane/n-C18 ratios (0.06–0.54), and predominant regular sterane C29. All biomarker parameters clearly indicate that the crude oil was derived mainly from algae and aquatic plankton and deposited under weak reduction-oxidation environment, and has the characteristics of mixed kerogens. The Cretaceous crude oil was mainly derived from the Triassic lacustrine source rocks, which also contributed to the Paleogene crude oil together with Jurassic coal source rocks. Natural gas is characterized by moderate methane content, high heavy hydrocarbon and nitrogen content, and no hydrogen sulfide. The methane and ethane in Paleogene natural gas are relatively rich in 13C with δ13C1 and δ13C2 values ranging from −37.3‰ to −31.2‰ (mean = −34.25‰) and from −25‰ to −21.3‰ (mean = −23.09‰), respectively, indicating the coal-derived gas from the Middle and Lower Jurassic strata. Hydrocarbon products in the southern slope zone of the Kuqa foreland basin are primarily generated from source rocks in the mature stage. The low-amplitude structural and lithologic traps with the updip pinch-out sand bodies or plugging secondary fault at relatively high tectonic positions are the most favorable areas for discovery and breakthrough in the study area. Results of this study will provide useful information for controlling factors of reservoirs and oil and gas exploration deployment in the southern slope zone of the Kuqa foreland basin. [ABSTRACT FROM AUTHOR]

Hydrocarbon distribution in the western Qaidam Basin is complex and characterised by large reserves, dispersed distribution, local enrichment, and multi-layer accumulation. Near the Altyn Tagh Ranges, the traps are mainly oil-filled, whereas far away and near the basin centre, they are gas-filled. With hydrocarbon distribution in the western Qaidam Basin poorly understood, the tectonic evolution, source-rock thermal evolution and space–time configurations were studied using burial history, strata thickness, source-rock generation and expulsion processes, and trap formation. Mode 1 system was characterised by continuous hydrocarbon accumulation, rapid source-rock burial and trap formation early in the basin history resulting in early generation and trapping of low maturity oil and later generation of high maturity oil. Mode 2 was characterised by mid-section hydrocarbon accumulation, steady source-rock burial velocity and trap formation with the traps filled by mature oil and small amounts of gas. Mode 3 was characterised by tail hydrocarbon accumulation, rapid source-rock burial and trap formation late in basin development resulting in traps filled with high-maturity gas. In the Mesozoic–Cenozoic petroleum system, such as the Dina2 condensate gas field, hydrocarbon accumulation was earlier than in the Yingxi Shizigou oilfield belonging to the Cenozoic petroleum system, which was mainly controlled by tectonic evolution and source-rock thermal evolution. The well-matching relationships between hydrocarbon generation–expulsion time and trap formation may create a giant oilfield, an earlier formed trap, later matured source rock and good preservation leading to continuous accumulation of hydrocarbon favourable for exploration. In the western Qaidam Basin, hydrocarbon differential distribution was mainly controlled by source-rock burial history, stratigraphic thickness and trap formation processes. Multi-stage hydrocarbon accumulation characteristics are classified into three modes according to the thermal evolution stage of the source rock. A comparison of hydrocarbon accumulation processes between the Yingxi oilfield in the western Qaidam Basin and Dina 2 gas fields in the Kuqa foreland basin allowed hydrocarbon accumulation modes to be determined. [ABSTRACT FROM AUTHOR]

Extended shallow carbonate platform, pelagic, and drift deposits were drilled during International Ocean Discovery Program (IODP) Expedition 359 in the Inner Sea of the Maldives. These sediments yield rich and well-diversified benthic, planktonic foraminiferal and nannofossil assemblages spanning from the early Oligocene to the Recent. We present here the shore-based revised integrated biostratigraphy of these microfossil groups at IODP Hole 359-U1468A together with the paleobathymetric reconstruction. Our data suggests the presence of a late Oligocene carbonate platform, marked by the shallowest water depths of the entire sequence of around 80 m. This carbonate platform sequence occurred from around 29 Ma, the extrapolated minimum age estimate, at least up to 27.5 Ma and possibly up to 25.4 Ma. Up the sequence, similar carbonate production conditions occurred until 22.5 Ma across the Oligocene–Miocene transition, equated at 23.04 Ma, with increased water depths >120 m. Notably, in the time interval approximately from 24 to 21.5 Ma, orbitally induced sapropel layers indicate a change of open to restricted circulation. However, at around 22.5 Ma, pelagic deposition at a distal slope occurred with sedimentation rates of 3 cm/years. This initially occurred in water depths of >350 m but gradually reached deposition in water depths of >500 m, which persisted from 21.12 Ma until approximately the extrapolated age of 12.8 Ma. Sedimentation rates gradually increased to 10.5 cm/1000 years at around 450 m below sea floor, marking the initiation of the drift sequence as identified in seismic lines with an age estimate of 12.8 Ma. The initiation of the drift sequence is also marked by a drastic decrease in the preservation of benthic and planktonic foraminifera from good to very poor at around 12.8 Ma. The drift sequence essentially continued to the present day but was interrupted by two events: the deposition of distinct shallow water benthic shoals and a large hiatus. From 12.8 Ma, a shallowing upward bathymetry is suggested by the occurrence of shallow benthic foraminiferal assemblages that close to around 11.93 Ma reached a maximum water depth of 80 m. This shoal then prograded into the basin and persisted at least until 9.89 Ma. Basin conditions with water depths exceeding 500 m were re-established in the upper part of the sedimentary succession after a hiatus spanning approximately from 9.83 Ma to 2.39 Ma, implying that renewed open ocean conditions occurred in the Pliocene–Pleistocene part of the sedimentary record. [ABSTRACT FROM AUTHOR]

The current saline state the Black Sea is only the latest of a series of freshening‐salinization episodes that have affected that body of water during past glacial‐interglacial cycles. Here, we model the salinity history of the basin and its sedimentary porewaters since the end of the penultimate saline period, variously thought to have occurred in the period between 128 and 65 Kyrs BP (Before Present). Our results argue that the down‐core salinity profiles of Black Sea Holocene sediments have been affected by upward diffusion of salt from the penultimate saline episode and possibly from residual salinity of the basin waters captured in the accumulating porewaters. Our retrodictions require that the Black Sea bottom waters be either fresh or weakly brackish (S ≤ 4), between 80 and 10 Kyrs BP. In addition, we find that the timing of the first deposition of the Holocene sapropel corresponds to the time when salty bottom waters first reached the surface waters, and we speculate that increased organic matter production was caused by the release of nutrients stored in the saline bottom water. Finally, using current salinity proxy data, we find that the porewater salinity profiles generated from these proxies do not match the observed interstitial profiles. Plain Language Summary: The Black Sea has changed from a freshwater or mildly brackish lake to a salty inland sea over the past 10,000 years, as Mediterranean Sea water invaded, starting at about that time. Those salinity changes are recorded in the porewaters preserved in the accumulating sediments at the bottom of that sea. However, past attempts with models to explain the changes in salinity with depth in those sediments have not accounted for the freshwater‐to‐saltwater history of the Black Sea. There was a previous saline period between about 128 and 65,000 years ago (BP), which is preserved deeper in the sediment. That porewater salt is slowly leaking back into the more recent saline porewaters via diffusion and that has not been taken into account by previous models. When that history is included, the available data can be predicted. Key Points: We present and solve models for the evolution of the salinity of the Black Sea and its sediments from the Eemian to the HoloceneThe correspondence between available data and our model results from inclusion of memory of the previous Eemian‐post‐Eemian salinizationAvailable porewater data do not appear to be consistent with hindcasts from available salinity proxies [ABSTRACT FROM AUTHOR]

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Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ni-containing catalysts are obtained on the basis of carbon mineral supports produced using sapropel and studied during the catalytic hydroliquefaction of sapropel. It is found that catalysts on supports obtained from mineral-type sapropel are more active than ones on supports based on organic-type sapropel, while bimetallic NiW catalysts exhibit higher activity than monometallic nickel catalysts, regardless of the nature of the support. It is shown that both the nature of the deposited metal and the support composition affect the conversion of the organic matter of sapropel and the composition of liquid products. The liquid products of hydroliquefaction contain mainly nitrogen- and oxygen-containing compounds. The maximum yield of hydrocarbons C5–C21 is obtained for catalysts on supports obtained from mineral-type sapropel. Liquid products of hydroliquefaction of sapropels are similar in composition to biofuels from other renewable raw materials and can be included in existing schemes for further processing. [ABSTRACT FROM AUTHOR]

The Cd, Hg, Zn, Pb and U contents in sapropel lakes depend on the amount of organic matter in the bottom sediments. Ignatovicîus and coauthors [[2]] show that anthropogenic factors and paleoenvironmental conditions are reflected in the heavy metal distribution in cores from sapropel lake sediments from suburban territories of Vilnius, Lithuania. These main factors cause the different contents and patterns of heavy metal accumulation, as well as diagenetic transformation in sediments of the two studied lakes. [Extracted from the article]

Data on the synthesis of carbon-mineral materials (CMM) through carbonization of native sapropel after preliminary mechanical activation (MA) in the air environment are presented. The effect of MA parameters (time, the size and acceleration of milling bodies) on the fractional composition and morphology of sapropel is investigated. MA for 5‒10 min promotes the dispersion of sapropel particles, while a further increase in treatment time causes their partial agglomeration. It is demonstrated that preliminary MA of native sapropel leads to changes in the texture parameters and acidity of the surface of CMM obtained after the carbonization stage. An increase in specific surface area from 90 to 560 m2g-1 is observed, with an increase in the adsorption pore volume from 0.16 to 0.52 cm3g-1 as a result of an increase in the fraction of micropores in the formed CMM. Despite this fact, CMM samples still contain large pores, and the fraction of meso- and macropores is 70%. In addition, a decrease in pH of the point of zero charge occurs as a consequence of an increase in the content of acidic oxygen-containing groups. The discovered effect is essential for the formation of sapropel-based materials with required properties and for broadening their application area.

The aim of this paper was to study the microbiological stability of bio-based composite building materials, which are made using organic-rich lake sediments (further – sapropel) with lime and magnesium cement as binders and hemp shives as filler. The microbial stability properties of the obtained composite materials were investigated and compared to similar composites. Because of their high organic content, these materials are prone to biodegradation; therefore, they were coated with ALINA LIFE TM organoclay coating, which helps to extend the product life, reducing the rate of biodegradation compared to the biocides used in industry. The effect of the coating on the resistance to decay by the Aspergillus versicolor, Penicillium chrysogenum, Alternaria alternata, Cladosporium herbarum, Chaetomium sp. and Trichoderma asperellum fungi was investigated under different conditions: relative humidity modes of 75% and 99% at 20°C for 45 days and four months. The results indicated that the composites made of sapropel and lime have similar microbial stability properties as lime and magnesium cement binder composite materials. ALINA LIFE TM organoclay coating showed advanced resistance to biodegradation; sapropel-lime composites have shown several good properties that make them suitable to be considered for use in the construction material industry.

The Gulf of Corinth represents an ideal setting for studying the impact of sea level changes and regional climate on a semi-enclosed, syn -rift basin. Here we investigate the stratigraphic and paleoceanographic variability recorded in the sedimentary succession of the basin over the Marine Isotope Stage (MIS) 5 period when global sea level and climatic conditions along the eastern Mediterranean exhibited pronounced fluctuations. We used sedimentological (granulometry, composition), micropaleontological (planktic and benthic foraminifera), and isotopic (stable δ18O, δ13C, and clumped isotope) proxies on core samples from site M0079A (IODP Expedition 381) combined with additional data from the expedition overview and records from the surrounding area. The sedimentary succession comprises an alternating pattern of a) bioturbated, biogenic-rich deposits associated with increased hemipelagic sedimentation with b) partly bedded, detrital-rich sediments attributed to intercalated sediment gravity flows within the hemipelagic background under low oxic sea-surface conditions, and c) aragonite-rich laminated deposits, indicating either transitional conditions between marine and isolated environment or a highly stratified seawater column and low oxygen seafloor conditions. We find that the Gulf of Corinth lay under marine conditions for nearly the entire MIS 5 period, while the Rion sill would have been possibly shallower, even 10 m, than the current depth. Nevertheless, water exchange was restricted during the MIS 5a – MIS 4 transition when the sea level fluctuated very close to the sill height. The hydrological conditions within the Gulf during most of the highstands MIS 5a, 5c, and 5e reflect higher oxygen levels and/or increased nutrient availability compared to the Holocene and present-day regime. The combined effects of Ionian Sea inflows and enhanced riverine runoff led to increased water column stratification and low oxygen, eutrophic seafloor conditions in the Gulf of Corinth during times of high precipitation in southern Europe and deposition of sapropels S3, S4, and S5 throughout the eastern Mediterranean. In contrast, during periods of widespread cold and arid conditions in the eastern Mediterranean, water column mixing was intense within the Gulf. Prevalent marine conditions are also proposed during the MIS 5b and 5d lowstands, yet associated with predominately bedded-detrital sediments in the Gulf. A complementary investigation in the adjoining Patras Gulf is suggested to fully comprehend the dynamics of climate and sea level changes in complex rift systems. • The Gulf of Corinth lay under marine conditions for nearly the entire MIS 5 period. • Three sedimentary facies associations characterize the MIS5 succession in the Gulf. • Hydrological conditions reflect eastern Mediterranean Sea trends and regional climate. • Higher sea-surface O 2 and/or nutrients at MIS5 highstands compared to the Holocene. • The western sill-boundary (Rion) had possibly been even 10 m shallower than present. [ABSTRACT FROM AUTHOR]

The Yangtze Block is a highly prospective area for Ediacaran natural gas exploration in recent years, especially the Doushantuo Formation, a vital source rock for organic-rich hydrocarbon and a shale gas reservoir in the region. However, understanding of the Ediacaran organic-rich source rocks systematically has been limited due to the heterogeneous accumulation of organic matter and confusing paleoclimatological and paleoceanographic conditions. Such a scenario is not conducive to further exploration of the deep Ediacaran natural gas resources or understanding the evolution of early Earth. In this study, based on two new well drillings in the northeastern Sichuan Basin, the integrated sedimentological and geochemical investigations were focused on the Ediacaran middle−upper Doushantuo Formation (DST) fine-grained rocks interval. Results show this set of black organic-rich shales (total organic carbon up to 13.97%) deposited under episodic warming climate during an otherwise protracted cooling trend. These frequent climatic fluctuations intensified hydrological circulation, which together with the concurrent hydrothermal activity and the Neoproterozoic Oxidation Event, led to eutrophication of surface seawater. Under these circumstances, a substantial enhancement in primary productivity driven by algae blooming, subsequently resulted in consume excess dissolved oxygen in seawater during the degradation stage and anoxic-euxinic bottom water expansion. Consequently, the high paleoproductivity controlled the extreme organic matter enrichment during the Doushantuo time and formed the DST 4 organic-rich shales in the Chengkou and Nanhua subbasins. In contrast, although the DST 3 shales still deposited under a high productivity condition, the shallower sedimentary environments with anoxic-oxic bottom water conditions resulted in greater variation in total organic carbon contents. • Extreme organic matter enrichment occurred in the Ediacaran Doushantuo shales. • High productivity is responsible for excessive organic carbon burial. • Frequently P-bearing upwelling creates Ediacaran nutrient-rich oceans in South China. • Coupling of climate with environment governs heterogeneous TOC distribution. [ABSTRACT FROM AUTHOR]

Human-induced carbon emissions are altering the modern climate, with severe repercussions on ecosystems. Among others, anthropogenic pressure is causing deoxygenation of the bottom water, with the widespread establishment of hypoxic zones in several Mediterranean areas. The geological archives allow investigating past deoxygenation dynamics (sapropel events) and their impact on marine ecosystems. Here, we compare the causes and the evolution of deoxygenation dynamics which occurred during two different time periods (Messinian and Holocene) in different paleoceanographic settings based on their micropaleontological content. The Messinian sapropel events are the result of increased export productivity during a relatively cold and arid context, triggering bottom anoxic conditions. The Holocene sapropel formed in response to weakening/stopping of the thermohaline circulation due to increasing temperature and freshwater input. Our results suggest that the deoxygenation dynamics in the Mediterranean in the near future will not follow the trend characteristic of the Holocene deep-sea sapropel because of the predicted drying trend. Differently, the paleoceanographic setting triggering the Messinian shallow-sea sapropels is comparable with the modern situation in different Mediterranean areas, where human-induced eutrophication is promoting deoxygenation. Based on these results, we suggest that the patchy deoxygenation trend in the Mediterranean Sea caused by climate warming may lead to a drastic change in the ecosystem services which would likely impact human activities.

When developing new innovative building materials, their performance characteristics as well as their environmental friendliness are important. It is difficult to produce a fully ecological material for building envelopes, because there is a lack of ecological binding materials on the market, good binding materials are very expensive, and cheaper ones have poorer adhesive properties and performance characteristics. In this work, natural organic sapropel was used as an ecological binder. Before use, an organic sapropel was additionally mechanically activated. Its activation efficiency was evaluated on the basis of consistency and tensile strength. Sapropel activation increased its consistency from 112 to 168 mm and its tensile strength from 466 to 958 kPa. Wood processing waste was used as a filler for the thermal insulation biocomposite. Additionally, the wood waste was chopped to regulate the density and main performance properties of the biocomposite. The density of the biocomposite was also regulated using different amounts of sapropel and the degree of compaction of the composite mixture. In this work, the influence of the amount of sapropel, the level of compression of the biocomposite mixture, and the size of the wood waste particles on the thermal conductivity and compressive stress of the biocomposite was analyzed. It was found that the compression level had the greatest influence on both the compressive stress and thermal conductivity, up to 12 times and 43.3%, respectively.

2D and 3D seismic data and basin simulation were used to investigate the gas hydrate distribution and natural gas migration pathways in the Qiongdongnan Basin (QDNB). Hydrate-related amplitude anomalies and extensive bottom simulating reflectors (BSRs) were mapped within the uppermost part. Based on their seismic reflection characteristics, the three main types of natural gas migration pathways and their distributions in the QDNB were identified through high-resolution seismic data. Basin modeling was carried out to document the migration efficiency of different migration pathways and their effects on hydrate enrichment. The basin modeling results show the following: (1) Diapirs, fault structures, and fractures constitute the three main types of natural gas migration pathways that transport the thermogenic gas from the deep to shallow layers in the QDNB. (2) The three migration pathways impact hydrate enrichment in different ways. Diapirs and faults contribute significantly to hydrate enrichment due to their higher migration efficiency. In comparison, the migration efficiency of the fracture systems is lower, with minimal benefit to hydrate enrichment. (3) The natural gas hydrate in the QDNB is mainly distributed along the diapirs and deep faults and generally scattered around the fracture system. These conclusions indicate that the migration pathways in the QDNB are regionally distributed and are closely related to hydrate accumulation. [ABSTRACT FROM AUTHOR]

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The Cretaceous clastic oil and gas reservoirs in the western Tabei area of the Tarim Basin are far away from source rocks (source-distal), and the hydrocarbons mainly originate from Triassic continental source rocks in the northern Kuqa Depression. Early exploration focused on structural oil and gas reservoirs, and yet, with deepening of exploration practice, exploration has shifted from structural oil and gas reservoirs to lithologic reservoirs. In such context, under guidance of the theory of migration and accumulation for source-distal reservoirs, the key accumulation period of Triassic source rocks is determined, and the migration path of oil and gas is clarified. According to the geological characteristics of the study area, the impression method and sequence ratio method are used to restore the paleoburial depth, and the Fillippone formula is used to restore the paleopressure. Based on Hubbert's theory, the paleofluid potential field of Triassic oil and gas in the Neogene Kangcun period is reasonably reconstructed. These combined with the planar structural evolution of Cretaceous reveal the preferential source-distal migration paths and directions of oil and gas. The favorable area of oil and gas accumulation is demarcated, and then, the facies belts with favorable lithology have been identified. The research results show the following: (1) The hydrocarbons of the Cretaceous oil and gas reservoirs originate from the Triassic source rocks. The Neogene Kangcun period is the key accumulation period. Hydrocarbons migrate to the western Tabei area along the Cretaceous basal unconformities and Late Yanshanian faults. (2) The paleofluid potential field of the Cretaceous during the key accumulation period shows the characteristics of "being high in the north and low in the south," which is consistent with the gradual decrease of fluid potential along the migration distance from the northern hydrocarbon generation center (Kuqa Depression) to the south slope, and coincides with the main distribution range of source rocks in the Kuqa Depression. On the basis of the aforementioned, four preferential source-distal migration paths and directions of hydrocarbons have been clarified, and the Yudong-Yingmaili area is confirmed as a favorable area for the source-distal migration and accumulation of hydrocarbons into the Cretaceous. (3) In terms of the favorable areas for source-distal oil and gas migration and accumulation to Cretaceous strata, the forward distal end and lateral flanks of the branched retrogradational delta are the favorable facies belts for the next exploration of lithologic oil and gas resources. The recent breakthroughs in the lithologic reservoirs of wells D7 and M46 have confirmed that the findings of this research on the preferential source-distal migration paths and accumulation positions of hydrocarbons are of great guiding values for exploration deployment of Cretaceous lithologic reservoirs far away from source rocks. [ABSTRACT FROM AUTHOR]

Found in lakes, freshwater sapropel is a sediment with a fine structure containing more than 10% of organic matter as well as residues of aquatic organisms with a small content of inorganic components of biogenic origin and mixture of mineral ingredients. The mud was first used in medicine by ancient Greeks, and it gained more popularity together with development of balneology in Europe in the 19th century as a remedy for several diseases. The last century also brought wider popularity in its cosmetic use. Despite its wide usage, mechanisms behind its effects are not so clear yet. Broad but fragmented studies on the effects of sapropel are available, but few have used modern research methods. There is evidence suggesting that its positive health effects are linked to its thermal capacity, ability of penetration in tissues and biological activity of its components, e.g., humic substances. Evidence also suggests antimicrobial activity and positive effects on skin regeneration. This review aims at summarising available knowledge on the structure and composition of sapropel and its effects on the human body, as well as its potential for further evidence-based use in medicine and cosmetics. [ABSTRACT FROM AUTHOR]

Hydrocarbon source rocks, as a main geologic factor of petroliferous systems in a sedimentary basin, play a key role in the accumulation of oil and gas and the formation of hydrocarbon accumulations. This study, which focuses on difficulties in prediction of hydrocarbon source rocks in basins or sags with low exploration degree and insufficient hydrocarbon source rock indicators, taking the Wenchang Formation of northern Zhu I Depression, Pearl River Mouth Basin as an example, proposed a hypothesis of "finding lakes and hydrocarbon source rocks". Detailed steps include, first , determination of the lacustrine basin boundary according to analysis of seismic foreset facies, determination of the depositional area based on the compilation of strata residual thickness maps, determination of the lacustrine basin shape according to deciphering slope break belt system, determination of the fluctuation of paleo-water depth according to biogeochemical indicators of mature exploration areas, determination of the lacustrine basin scale based on analyses of tectonics intensity and accommodation space, which prove the existence of the lacustrine basin and identify the range of semi deep-deep lake; second , further analyses of tectonopalaeogeomorphology, paleo-provenance, palaeoclimate and paleo-water depth to reconstruct the geologic background of the original basin and semi-deep-deep lacustrine facies, to determine the distribution of semi-deep/deep lacustrine sediments in combination with studies of logging facies, core facies, seismic facies and sedimentary facies, and to rank the sags' potential of developing hydrocarbon source rocks from controlling factors of source-to-sink system development; third , on the basis of regional sedimentary facies analysis, through identification and assessment of seismic facies types of semi-deep/deep lacustrine basins in mature areas, establishing "hydrocarbon source rock facies" in mature areas to instruct the identification and depicting of hydrocarbon source rocks in semi-deep/deep lacustrine basins with low exploration degree; fourth , through systematical summary of hydrocarbon-rich geological factors and lower limit index of hydrocarbon formation of the sags already revealed by drilling wells (e.g., sag area, tectonic subsidence amount, accommodation space, provenance characteristic, mudstone thickness, water body environment, sedimentary facies types of hydrocarbon source rocks), in correlation with corresponding indexes of sags with low exploration degree, then the evaluation and sorting of high-quality source rocks in areas with sparsely distributed or no drilling wells can be conducted with multi-factors and multiple dimensions. It is concluded that LF22 sag, HZ10 sag and HZ8 sag are II-order hydrocarbon rich sags; whereas HZS, HZ11 and HZ24 are the III-order hydrocarbon-generating sags. [ABSTRACT FROM AUTHOR]

This work aimed to conduct a laboratory study to evaluate the use of Pseudomonas putida CB-100 and nutrient addition for the removal of PAHs from an aged oil-polluted soil of Veracruz, Mexico. Pseudomonas putida is a biosurfactant-producing bacterium capable of metabolizing polycyclic aromatic hydrocarbons (PAHs), which are toxic compounds with low water solubility, high melting, and boiling points, and low vapor pressure; characteristics that increase as their molecular weight increases and make them more recalcitrant. The methodology consisted in sampling the long-term oil-polluted soil and testing the use of Gamma irradiation (25 kGy) for the sterilization of the soil for abiotic control. We evaluated serological bottles containing 20 g of 35% moist soil (irradiated and non-irradiated) with the following treatments: the addition of nutrients (NH4Cl, NaNO3, KH2PO4, and K2HPO4), an inoculum of P. putida, and both P. putida and nutrients. The parameters assessed were pH, organic matter, humidity, available phosphorus, total nitrogen, cultivable heterotrophic microorganisms, CO2 production, rhamnolipids, surface tension, and the removal of eleven PAHs. The non-irradiated soil added with P. putida was the most efficient in the removal of PAHs; the pattern was: Benzo(a)anthracene > Phenanthrene > Fluoranthene > Benzo(k)fluoranthene > Chrysene > Pyrene > Anthracene > Acenaphthylene > Benzo(b)fluoranthene. In conclusion, P. putida in the non-irradiated soil produced in situ biosurfactants (1.55 mg/kg of rhamnolipids and an 11.9 mN/m decrease in surface tension) and removed PAHs in 10 days. [ABSTRACT FROM AUTHOR]

Data on the synthesis of carbon-mineral materials (CMM) through carbonization of native sapropel after preliminary mechanical activation (MA) in the air environment are presented. The effect of MA parameters (time, the size and acceleration of milling bodies) on the fractional composition and morphology of sapropel is investigated. MA for 5-10 min promotes the dispersion of sapropel particles, while a further increase in treatment time causes their partial agglomeration. It is demonstrated that preliminary MA of native sapropel leads to changes in the texture parameters and acidity of the surface of CMM obtained after the carbonization stage. An increase in specific surface area from 90 to 560 m²2g-1 is observed, with an increase in the adsorption pore volume from 0.16 to 0.52 cm³g-1 as a result of an increase in the fraction of micropores in the formed CMM. Despite this fact, CMM samples still contain large pores, and the fraction of meso- and macropores is 70%. In addition, a decrease in pH of the point of zero charge occurs as a consequence of an increase in the content of acidic oxygen-containing groups. The discovered effect is essential for the formation of sapropel-based materials with required properties and for broadening their application area. [ABSTRACT FROM AUTHOR]

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The vague understanding of the coupling relationship among natural gas charging, reservoir densification, and pressure evolution restricted the tight gas exploration in the Lower Shihezi Formation of the Hangjinqi area, north Ordos Basin. In this study, the quantitative porosity evolution model, the pressure evolution process, and the natural gas charging history of tight sandstone reservoirs were constructed by integrated investigation of the reservoir property, the thin section, SEM and cathode luminescence observations, the fluid inclusion analysis and the 1D basin modeling. The results show that the compaction and cementation reduced the primary porosity by 21.79% and 12.41%, respectively. The densification of the reservoir occurred at circa 230 Ma, which was before the natural gas charging time from 192 to 132 Ma. The paleo-overpressure within the tight reservoirs occurred since the Middle Jurassic with the pressure coefficients between 1.1 and 1.55. The continuous uplifting since the Late Cretaceous resulted in the under- and normal-pressure of the Lower Shihezi Formation with the pressure coefficients ranging from 0.67 to 1.05. The results indicate that the densification of the reservoirs was conducive to the formation of paleo-pressure produced by gas generating. The gas predominantly migrated vertically, driven by gas expansion force rather than buoyance and displaced the pore water in the reservoirs near source rocks. [ABSTRACT FROM AUTHOR]

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At the beginning of the experiment, the weight of weekly cockerels of the Hisex White egg cross (n = 90) was 64.6 ± 0.47 g. At the age of one week old, 3 groups (30 birds in each group) were formed. They received complete feed. The first group served as a control. The chickens of the second and third groups received combined fodder, in which 3% and 5% of the feed weight was replaced with dry sapropel. The dry sapropel (3% of the daily feed weight) increased the activity of casein-lytic and hemoglobin-lytic peptidases in the chyme by 1.5 (Р

East African climate change since the Late Miocene consisted of persistent shorter-term, orbital-scale wet-dry cycles superimposed upon a long-term trend towards more open, grassy landscapes. Either or both of these modes of palaeoclimate variability may have influenced East African mammalian evolution, yet the interrelationship between these secular and orbital palaeoclimate signals remains poorly understood. Here, we explore whether the long-term secular climate change was also accompanied by significant changes at the orbital-scale. We develop northeast African hydroclimate and vegetation proxy data for two 100 kyr-duration windows near 3.05 and 1.75 Ma at ODP Site 967 in the eastern Mediterranean basin, where sedimentation is dominated by eastern Sahara dust input and Nile River run-off. These two windows were selected because they have comparable orbital configurations and bracket an important increase in East African C4 grasslands. We conducted high-resolution (2.5 kyr sampling) multiproxy biomarker, H- and C-isotopic analyses of plant waxes and lignin phenols to document orbital-scale changes in hydrology, vegetation and woody cover for these two intervals. Both intervals are dominated by large-amplitude, precession-scale (approx. 20 kyr) changes in northeast African vegetation and rainfall/run-off. The δ(13)Cwax values and lignin phenol composition record a variable but consistently C4 grass-dominated ecosystem for both intervals (50-80% C4). Precessional δDwax cycles were approximately 20-30‰ in peak-to-peak amplitude, comparable with other δDwax records of the Early Holocene African Humid Period. There were no significant differences in the means or variances of the δDwax or δ(13)Cwax data for the 3.05 and 1.75 Ma intervals studied, suggesting that the palaeohydrology and palaeovegetation responses to precessional forcing were similar for these two periods. Data for these two windows suggest that the eastern Sahara did not experience the significant increase in C4 vegetation that has been observed in East Africa over this time period. This observation would be consistent with a proposed mechanism whereby East African precipitation is reduced, and drier conditions established, in response to the emergence of modern zonal sea surface temperature gradients in the tropical oceans between 3 and 2 Ma.This article is part of the themed issue 'Major transitions in human evolution'.

Despite the EU's ambitious goals regarding the expansion of marine renewables as a promising climate mitigation and energy security measure, the majority of hydrocarbon exploitation continues occurring offshore with more than 500 oil and gas installations operating in European seas. Given the grave environmental risks these activities pose, the EU has developed secondary rules with implications for the regulation of offshore energy generation. These normative developments have added an extra layer of regional, supra-national regulation of ocean energy production across European seas, which necessarily interacts with the simultaneously applicable rules under regional sea agreements. The article examines the implications of the normative interplay between EU law and regional sea agreements in terms of shaping the environmental regulation of offshore energy production across Europe. In that respect, it explores whether EU law instruments and the EU's sophisticated institutional framework can enhance the rules and standards under the regional sea agreements, in terms both of adding normative content to them and supporting their enforcement. In light of the mutual cross-fertilization between the two applicable regimes, the article equally looks into the normative impact of regional sea conventions on the EU legal framework and its implementation in the context of offshore energy production. [ABSTRACT FROM AUTHOR]

Soil pollution has become an issue of concern with the development of industrialization. In situ gas thermal remediation is a suitable remediation technology for heavily organic contaminated soil, yet its high energy consumption limits the application. In this study, three energy-saving strategies, off-gas burn-back mode, heat-returning mode, and air-preheating mode, were proposed, and their natural gas consumption and energy utilization ratio were analysed. A mathematical model was established for the heat and mass transfer in unsaturated soil by employing conjugate heat transfer. The temperature of the soil and flue gas, and the concentration of components in the soil and off-gas were simulated, which indicated the thermal behavior of the contaminated soil and the timing for operation control. Models of burners were also developed under different energy-saving modes for energy analysis. By comparing the basic method, adopting the off-gas burn-back mode obtained an energy-saving effect of 3.37%, which relied on the content and calorific value of the pollutant in the off-gas. Under combustion air-preheating ratios of 0.5 and 1.0, natural gas could only be saved by 13.56% and 18.88%, respectively. In general, the most effective energy-saving measure was the heat-returning mode, by which 21.44% of natural gas could be saved when the reflux ratio of the flue gas was 0.5. [ABSTRACT FROM AUTHOR]

We characterised the organic matter content of marine deposits at the Oxfordian-Kimmeridgian transition in the Boulonnais (France). Organic rich deposits in platform environments are evidenced in the uppermost Cymodoce and lowermost Mutabilis Zone (early late Kimmeridgian), associated with enhanced planktonic palaeoproductivity and/or developing dysoxia/anoxia. Similar organic rich intervals in early late Kimmeridgian are also evidenced in platformdeposits in Normandy and Charentes in France, and in basinal deposits from Yorkshire and Dorset in UK. This refined onset of the organic rich bands (ORB), as described in NW Europe during the late Jurassic, is coeval with seawater warming. We propose that this seawater warming was an important trigger of the onset of the late Jurassic ORB deposition system in NW Europe, which began at the Cymodoce-Mutabilis boundary during the early late Kimmeridgian and lasted until the middle part of the Tithonian, over a time span of 6.8Myr. [ABSTRACT FROM AUTHOR]

Copyright of News of Kazakhstan Science / Novosti nauki Kazahstana is the property of NCSTE (JSC National Center for State Scientific and Technical Evaluations) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The structure of integrated mechanization of individual technological operations for obtaining peat-sapropel fertilizers, including extraction and processing of raw materials, is considered. [ABSTRACT FROM AUTHOR]

The paper presents an analytical review of studies that discuss issues concerning the geochemistry of organic matter in Jurassic–Cretaceous rocks in the Arctic regions of Western Siberia and genetically related oils, gas condensates, and hydrocarbon gases. The Late Jurassic Bazhenov Formation and the coeval Golchikha (upper part) and Yanovstan (middle part) Formations are regarded as the major oil-source rocks in this region. Unlike the classic Bazhenov Formation in the central areas of Western Siberia, the Late Jurassic oil-source marine organic matter (OM) in the Arctic region is characterized by an admixture of terrestrial biomaterial and oxidizing conditions during diagenesis, with these features reflected in its composition of the OM and the related oils and gas condensates. These hydrocarbon fluids were accumulated mostly in Early Cretaceous rocks. The other oil-source rocks in the area are those of Early–Middle Jurassic formations enriched in mixed highly mature organic matter: the Zimnyaya, Sharapovo, Kiterbyut, Laida, and Malyshev. Oil and gas condensates generated in these formations were detected in the Middle Jurassic rocks (in the Yenisei–Khatanga area and in the eastern part of the Gydan Peninsula), and in the Jurassic and Cretaceous rocks (in the Yamal Peninsula and in the western Gydan Peninsula). Other rocks thought to have been able to generate oil in the area are the shale beds enriched in marine organic matter of the poorly studied Late Jurassic Sigov and Abalak Formations and the lower strata of the Early Cretaceous sedimentary sequences (Nizhnyaya Kheta, Shuratov, and Akh Formations). The almost whole Jurassic–Cretaceous rock complex is thought to be gas-producing. However, the main gas-generating rocks are thought to be those of Early–Middle Jurassic age and the Late Jurassic rocks with highly mature organic matter. The source of isotopically light dry gases of the Aptian–Albian–Cenomanian formations are reportedly the terrestrial (carbonaceous) organic matter in the Cretaceous rocks affected by early catagenic transformations. The contribution of the early catagenic gases to the gas potential of this region is debatable. Oil and gas generation centers in Arctic Western Siberia are localized in the most strongly subsided depression zones of the area and south of it. It should be noted that much published data on the geochemistry of organic matter are unsystematic and heterogeneous, and hence, detailed geochemical studies of the Jurassic–Cretaceous rocks of this area as a whole shall be carried out, with primarily focus on its northernmost parts. [ABSTRACT FROM AUTHOR]

The paper reports the results of the analysis of Pb, Sb, Cd accumulation in top core sediments from small lakes of southern Republic of Karelia. Both lakes in urban areas (Petrozavodsk, Medvezhyegorsk, Suojarvi, and Sortavala) and lakes in areas regarded as reference for southern Karelia were included in the study. Fieldwork and analytical investigations employed a common methodology in line with globally-accepted limnological practices. The concentrations of chemical elements in the lake sediments were determined by inductively coupled plasma mass spectrometry (ICP-MS). The median background concentrations of Pb, Sb, Cd in the studied sediments deposited in the preindustrial period were calculated, and the recent levels of accumulation of these metals in the industrial period were determined for the same lakes. The main factors for the formation of technogenic Pb, Sb, Cd anomalies in the top core sediments are described, and the levels of the heavy metals are compared against those in lake sediments in other parts of the world. The levels of contamination of the Karelian lakes with these metals were calculated based on the geoaccumulation index Igeo. The Tessier sequential extraction procedure was employed to detect the main forms of the heavy metals in the top core sediments. Especially, the role of organic matter, which constitutes the bulk of the sediments, in binding the pollutants was assessed. Considering that Karelian lake sediments are potential sources of useful organic raw material, i.e. sapropel, some recommendations are given on the possible applications of these sediments in human activities.

To address the need to reduce consumption and pollution in the industrial sector, composite materials were created using a new type of raw materials—organic lake sediments (sapropel) as a binder; sphagnum moss, flax fiber, and vermiculite as a filler. The main application of these composite materials is for sound absorption and moisture buffering, but since they contain bio-based binders and fillers, they also work as carbon storage. Within the framework of this work, a total of 100 samples of composite materials were created. Fungicides—a biocide quaternary ammonium compound and its natural substitute montmorillonite mineral material were also added to the materials to improve microbiological stability. The mechanical sound absorption and microbiological properties of materials were investigated and compared to similar environmentally friendly materials, such as hemp-lime concrete (FHL), hemp magnesium oxychloride composite (MOC), and hemp magnesium phosphate cement (MPC). The results showed that sound absorption and mechanical and microbial properties of the created composite materials are sufficient for their intended use, with flax fiber and vermiculite composites showing more stable mechanical, sound absorbing, and microbiological stability properties than materials containing flax fiber and moss.

Nickel catalysts with carbon-mineral supports derived from sapropel were synthesized; the effect exerted by the nature of the support (type of the initial sapropel) and active component precursor on the activity of the catalysts in the model reaction of liquid-phase nitrobenzene hydrogenation was studied. The catalysts, synthesized using the support with a smaller fraction of carbon, were more active irrespective of the precursor nature. The highest activity was observed for the catalysts synthesized from nickel nitrate and formate; nitrobenzene conversion was 65% and 51%, respectively, after 1 h of reaction. The catalysts retained high activity after six reaction cycles at 100% aniline selectivity. The presence of sulfur in the nickel precursor deteriorated the catalytic activity (convection less than 3%) due to formation of the sulfide phase.

To this end, stable carbon ( SP 13 sp C) and oxygen ( SP 18 sp O) isotope ratios of dental carbonates from both archaeological and modern samples from Boodie Cave (Barrow Island) were analysed. Thanks to this study, the authors were able to conclude that skipjack tuna in western Taiwan had a slightly higher trophic position and that opportunistic predation may result in different predator-prey size dynamics between regions (stable isotope values increased with body size in eastern Taiwan). 33805066 7 Chang Y.-C., Chiang W.-C., Madigan D.J., Tsai F.-Y., Chiang C.-L., Hsu H.-H., Lin S.-M., Zhuang M.-Y., Sun C.-T., Chen L.-C. Trophic Dynamics and Feeding Ecology of Skipjack Tuna (Katsuwonus pelamis) off Eastern and Western Taiwan. [Extracted from the article]

The change in the plant growth parameters is shown in model experiments by the example of various commercial high-yielding varieties of green peas (Sofia, Alfa, and Triumf) cultivated in sod-podzolic soil, when a toxic concentration of copper ions (165 mg/kg) and an ultradisperse humate-sapropel suspension (UDHSS) (0.005%–50 ppm) were introduced into the environment. The experiments were carried out two times in four repetitions for each variant under controlled conditions of intensive photoculture. It is shown that for all varieties, the introduction of the metal led to a decrease in the yield, by 57% for the varieties of Alfa and Sofia and by 45% for the Triumf variety. Moreover, in the latter, according to the ratio of inhibition of the biomass of the aboveground/underground organs, the root system turned out to be more stable to the toxicant effect. The average indices of root biomass reduction were only 29%, while for the other two varieties they were 52–62% of the control. When the substrate was contaminated, the Triumf variety differed in having values of copper accumulation in its biomass two times lower than the other two, which, in terms of the degree of tolerance, makes it rather a phytoexcluder for this metal. In addition, soil contamination with toxic copper led to an increase in the total chlorophyll content in the leaves of the Triumf peas by 15%, which is probably also associated with activation of the mechanism of nonspecific compensatory responses of the cultivar adaptation to stress. The introduction of the UDHSS into the medium neutralized the toxic effect of copper in all the above parameters towards the control. [ABSTRACT FROM AUTHOR]

Screening of the dominant or core oil resistant bacteria in Aged Oil Sludge (AOS) contaminated soil in Daqing and Shengli oilfields (DQ and SL) in China was investigated through High-Throughput Sequencing method. Enhanced total organic carbon (TOC, 12.53 to 28.35 g/kg in DQ and 3.07 to 4.97 g/kg in SL) and total petroleum hydrocarbons (TPHs, 21 to 2837 mg/mg in DQ and 13 to 1558 mg/kg in SL) were observed. The internal transcribed spacer (ITS) sequencing by Illumine Miseq platform at each taxonomic level revealed the notable toxicological effect of AOS on the diversity and community structure of bacteria. In this study, sequence analyses showed 77–89% and 92–98% reduction of Firmicutes at phylum level in DQ and SL respectively after treated with AOS. Enhanced universal gene location was observed in Proteobacteria, Actinobacteria, Gemmatimonadetes and Bacteroidetes in DQ and SL. The universal dominant family in the two oilfields was anaerolineaceae. At the genus level, Algiphilus in DQ and Pseudomonas in SL were the majority respectively. In total, 3 negligible genera (Perlucidibaca, Alcanivorax and Algiphilus) in DQ and 13 negligible genera (Salinisphaera, Microbulbifer and Idiomarina, et al.,) in SL were significantly enriched after oil treatment indicating their possible role in the attenuation of petroleum hydrocarbons. [ABSTRACT FROM AUTHOR]