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Lake systems are among the largest integrated depositional complexes in the continental realm. Their interplay with tectonics and climate often complicates the interpretation of depositional processes, usually resulting in a complex facies architecture that is challenging to correlate regionally. The Lower to Middle Permian Roseneath–Epsilon–Murteree strata of the Cooper Basin in Australia represent a glacially influenced fluvial–deltaic lake system, which hosts substantial petroleum resources. Despite their potential, the Roseneath–Epsilon–Murteree strata are inadequately understood in terms of regional facies architecture and their palaeogeographical implications. Using a multidisciplinary approach with robust data, including cores, petrology, wireline logs and geochemistry, the sedimentary evolution of the Roseneath–Epsilon–Murteree strata is described within a new basin‐wide sequence stratigraphic framework defined by key surfaces identified from cores and wireline logs. Detailed facies analysis of over 1400 m of cores and wireline logs from nine wells identified twelve lithofacies and eight facies associations, revealing various depositional processes and environments. The Roseneath–Epsilon–Murteree strata are interpreted as having formed in a fluvial–deltaic–lacustrine system influenced by a cold climate. First‐order and second‐order maximum flooding surfaces define a regional sequence stratigraphic framework, subdividing the Roseneath–Epsilon–Murteree strata into four sequence units (SU1, SU2, SU3 and SU4), deposited during four phases (I, II, III and IV). Cyclic stacking patterns observed in both cores and wireline logs reveal two transgressive–regressive cycles. Palaeogeographical maps of the four depositional phases suggest that the Roseneath–Epsilon–Murteree strata were dominated by a lacustrine system with some delta and mire deposits. Rivers primarily drained towards the south/south‐west from the Gidgealpa, Merrimelia, Packsaddle and Innamincka ridges ('GMI Trend') as indicated by decreasing sandstone percentages and increasing gross unit isopach maps. The deposition of the Roseneath–Epsilon–Murteree strata was primarily controlled by basin subsidence. Additionally, palaeoclimate trends and extensive glaciation in the Permian played important roles in providing sediments and affecting lake level changes. The lake system recorded by the Roseneath–Epsilon–Murteree strata serves as an analogue for other fluvial–deltaic–lacustrine systems in basins worldwide. A multidisciplinary approach, similar to the one utilized in this study, can help to elucidate their evolution and aid in resource prediction. [ABSTRACT FROM AUTHOR]

Jurassic strata along the southern margin of Junggar Basin are important petroleum system elements for exploration in northwest China. The Lower and Middle Jurassic source rock effectiveness has been questioned as exploration progresses deeper into the basin. These source rocks are very thick and are distributed widely. They contain a high total organic carbon composed predominantly of Type III kerogen, with some Type II kerogen. Our evaluation of source rock petroleum generation characteristics and expulsion history, including one-dimensional basin modeling, indicates that Jurassic source rocks are gas prone at deeper depths. They reached peak oil generation during the Early Cretaceous and began to generate gas in the Late Cretaceous. Gas generation peaked in the Paleogene-Neogene. Source rock shales and coals reached petroleum expulsion thresholds at thermal maturities of 0.8% and 0.75% vitrinite reflectance, respectively, when the petroleum expulsion efficiency was ~40%. The petroleum generated and expelled from these source rocks are 3788.75 x [10.sup.8] and 1507.55 x [10.sup.8] t, respectively, with a residual 2281.20 x [10.sup.8] t retained in the source rocks. In these tight reservoirs, a favorable stratigraphic relationship (where tight sandstone reservoirs directly overlie the source rocks) indicates short vertical and horizontal migration distances. This indicates the potential for a large, continuous, tight-sand gas resource in the Lower and Middle Jurassic strata. The in-place natural gas resources in the Jurassic reservoirs are up to 5.68 x [10.sup.12]-15.14 x [10.sup.12] [m.sup.3]. Jurassic Badaowan and Xishanyao coals have geological characteristics that are favorable for coal-bed methane resources, which have an in-place resource potential between 3.60 x [10.sup.12] and 11.67 x [10.sup.12] [m.sup.3]. These Lower and Middle Jurassic strata have good shale gas potential compared with active US shale gas, and the inferred in-place shale gas resources in Junggar Basin are between 20.73 x [10.sup.12] and 113.89 x [10.sup.12] [m.sup.3]. This rich inferred conventional and unconventional petroleum resource in tight-sand, coal-bed, and shale gas reservoirs makes the deeper Jurassic strata along the southern margin of Junggar Basin a prospective target for future exploration. Les strates jurassiques le long de la bordure sud du bassin de Junggar constituent des elements importants d'un systeme petrolier exploitable dans le nord-ouest de la Chine. L'efficacite de la roche source (Jurassique inferieur et moyen) a ete mise en question a mesure que l'exploration progressait plus profondement dans le bassin. Ces roches sources sont tres epaisses et couvent de grandes etendues. Leur teneur en carbone organique total est elevee et il est principalement compose de kerogene de type III avec un peu de kerogene de type II. Selon notre evaluation des caracteristiques de generation de petrole a partir de roches souches et de l'historique d'expulsion, incluant une modelisation du bassin a une dimension, ces roches sources du Jurassique devraient contenir du gaz a de grandes profondeurs. Ces roches ont atteint un sommet de generation de petrole durant le Cretace precoce et elles ont commence a produire du gaz au Cretace tardif. La generation de gaz a atteint un sommet au Paleogene-Neogene. Les roches sources de shale et les charbons ont atteint des seuils d'expulsion du petrole a des maturites thermiques respectives de reflectance de la vitrinite de 0,8% et de 0,75%, alors que le taux d'efficacite d'expulsion du petrole est d'environ 40%. Le petrole genere par ces roches est de 3788.75 x [10.sup.8] t et celui expulse est de 1507.55 x [10.sup.8] t; 2281.20 x [10.sup.8] t residuelles sont retenues dans les roches sources. Dans ces reservoirs peu permeables, une relation stratigraphique favorable (lorsque des reservoirs de gres peu permeables reposent directement sur les roches sources) signale de courtes distances, verticales et horizontales, de migration, ce qui en retour indique un potentiel pour une vaste ressource ininterrompue de gaz dans un sable peu permeable de strates du Jurassique inferieur et moyen. Les ressources de gaz naturel in situ dans les reservoirs datant du Jurassique atteignent de 5.68 x [10.sup.12] a 15.14 x [10.sup.12] [m.sup.3]. Les charbons Badaowan et Xishanyao (Jurassique) possedent des caracteristiques geologiques favorables aux ressources de methane de houille, lesquelles ont un potentiel in situ entre 3.60 x [10.sup.12] et 11.67 x [10.sup.12] [m.sup.3]. Ces strates du Jurassique inferieur et moyen ont de bons potentiels de gaz de shale comparativement aux gaz de shale americains exploites, et les ressources in situ inferees dans le bassin de Junggar sont de 20.73 x [10.sup.12] a 113.89 x [10.sup.12] [m.sup.3]. Cette riche ressource de petrole inferee, conventionnelle et non conventionnelle, dans des reservoirs de sables peu permeables, de lits de charbon et de gaz de shale, font des strates jurassiques tres profondes le long de la bordure sud du bassin de Junggar une cible prometteuse pour de l'exploration future. [Traduit par la Redaction], Introduction Junggar Basin is one of the most petroliferous basins in China (Ulmishek 1984; Wang 2000b; Li et al. 2003; Kong 2007; Cao et al. 2012; Shao 2013). By 2010, [...]

Although it has been shown that the potential of tight-sand gas resources is large, the research into the mechanisms of hydrocarbon charging of tight sandstone reservoirs has been relatively sparse. Researchers have found that there is a force balance during hydrocarbon charging, but discriminant models still have not been established. Based on the force balance conditions observed during gas migration from source rocks to tight sandstone reservoirs, a calculation formula was established. A formula for identifying effective source rocks was developed with the gas expulsion intensity as the discrimination parameter. The critical gas expulsion intensity under conditions of various burial depths, temperatures, and pressures can be obtained using the calculation formula. This method was applied in the Jurassic tight sandstone reservoirs of the eastern Kuqa Depression, Tarim Basin, and it was calculated that the critical expulsion intensity range from 6.05 × 108 m3/km2 to 10.07 × 108 m3/km2. The critical gas charging force first increases with depth and later decreases with greater depths. The distribution range of effective gas source rocks and total expelled gas volume can be determined based on this threshold. This method provides new insight into and method for predicting favourable tight-sand gas-bearing regions and estimating their resource potentials. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The upper limit of maturity for hydrocarbon generation (ULMHG) is represented by vitrinite reflectance (VR) that corresponds to the point at which the amount of further hydrocarbon generation is less than 1 % of the total hydrocarbon generation. Six methods were employed to study the ULMHG of the Cambrian and Ordovician carbonate source rocks in the Tarim Basin Platform (TBP), based on the mechanism of hydrocarbon generation, retention, and expulsion. These methods are reduction in atomic ratio for organic elements, variation in hydrocarbon generation potential, optimum simulation of organic materials based on material balance principle, thermal simulation experiment, variation in hydrocarbon retention amount, and variation in hydrocarbon expulsion amount. Studies showed that, although there are some differences between the results obtained using different methods, these differences are small. The ULMHG in the TBP varies from 4.10 to 4.84 % with an average value of 4.55 %, which is in good agreement with the characteristics of hydrocarbon generation under actual geological conditions. The VR of the Cambrian and Ordovician carbonate source rocks in the Tazhong uplift, the Bachu uplift, and the Tabei uplift ranges from 0.64 to 2.34 %, indicating that these areas have not reached the ULMHG. The VR in the Tadong area is very close to the ULMHG, and the VR of most source rocks in the Manjiaer sag has exceeded the ULMHG. In summary, the carbonate source rocks in the TBP have generated large amounts of hydrocarbons and still have high hydrocarbon generation potential to form large-scale oil and gas reservoirs, indicating good hydrocarbon exploration prospects in the deep parts of the TBP. Therefore, the study of ULMHG of carbonate source rocks is of great significance for evaluating the oil and gas resource potential and predicting favorable exploration areas in deep or carbonate rock formations. [ABSTRACT FROM AUTHOR]

Objective: Study the cytotoxicity of toluene and its mechanism, the hippocampus neurons were primarily cultured and were exposed to toluene in vitro., Methods: The neurons from newborn SD rat's hippocampus were primarily cultured for two weeks, then administered with toluene (3, 6, 9 mmol/L), with blank control group and excipient group being also set up. 24 hours later, Morphology and viability of the cells, the LDH activity, [Ca2+]i, and cell apoptosis were examined., Results: Protuberances of neurons of the toluene-exposed groups were damaged; the bodies of the neurons became round and swollen; the number of the cells decreased; the LDH activity of neurons of high-dose group increased significantly compared with control group (P < 0.05). [Ca2+]i of toluene-exposed groups also increased significantly compared with control group(P < 0.05) in a dose-dependent manner; after diltizem as antagonist of calcium tunnel was added, no increase of [Ca2+]i was found; and evident apoptosis of the exposed cells were also found., Conclusion: Toluene was toxic to the neurons after being administered in vitro, which might be ascribed to higher lipid solubility of toluene and it's ability to increase calcium influx, the latter facilitating apoptosis.