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The Ordos Basin is the second largest sedimentary basin in China. The oil and gas resources in the basin are very rich, and there is great potential for oil and gas exploration and development. The Chang 6 member of the Triassic Yanchang Formation is the main oil-bearing formation of Huanjiang Oilfield. The Chang 6 reservoir of Huanjiang Oilfield currently has the problem of insufficient understanding ofreservoir geological laws, especially in the southern part of the oilfield. In this paper, the microscopic pore structure of the Chang 6 member ofHuanjiang Oilfield was systematically studied by means of mineral composition analysis, thin section analysis, scanning electron microscopy analysis and mercury intrusion experiments. Experimental results show that the Chang 6 reservoir in Huanjiang Oilfield is a low-porosity, ultra-low pe1meability reservoir, but there are still some relatively high porosity and high permeability reservoirs in some local areas. The Chang 6 reservoir has an average porosity of 7.43% and an average permeability of0.15x10-3 µm2. The pore types of the target layer are mainly intergranular pores and feldspar dissolution pores, and a small amount of lithic dissolution pores, intergranular dissolution pores, intercrystalline pores and microcracks are also developed. The mercury intrusion experiment showed that the pores of the Chang 6 member were poorly sorted and the pore structure was complicated. Diagenesis is the main factor affecting the pore structures of the reservoir. [ABSTRACT FROM AUTHOR]

Abstract Paleo-sedimentary environment of Chang 7 Member of Upper Triassic Yanchang Formation in Ordos Basin, including the paleoclimate, paleo-salinity and paleo-redox conditions were restored through geochemical elements analysis of 289 samples collected from the outcrop sections around and wells drilled in the basin and using a series of identification indexes of paleo-climate, paleo-salinity and paleo-redox conditions, such as CaO/MgO·Al 2 O 3 , Sr/Cu, Rb/Sr, Rb/K 2 O, Th/U, V/(V+Ni), the content of element B tested from the mudstone. Comprehensive analysis shows that in sedimentary period of the Chang 7, the paleo-climate was warm temperate to subtropical climate with temperature higher than 15 °C, the water body was continental brackish water to freshwater, and the sediments were deposited under strong reduction conditions. Suitable temperature, extensively deep lake basin and strongly reductive paleo-sedimentary environment led to the blooming, enrichment and preservation of organic matter in the submember Chang 7 3. As a result, a set of high-quality source rock was formed, laying material foundation for large-scale accumulation of shale oil. [ABSTRACT FROM AUTHOR]

Exploration for gas producing lacustrine shales in the Ordos Basin has identified considerable capacity in T 3 y7 shale in the Upper Triassic. The T3y7 shale is a black color, siliclastic organic rich lacustrine mudrock. The mineral components primarily include clay minerals, quartz and feldspar, with the brittle mineral (quartz, feldspar and carbonate) content accounting for 56 wt. %. The presence of type II kerogens, the high TOC contents (most 2%–4%), thermal maturation reaching the oil/gas window and constant organic-rich shale thickness indicate that optimum conditions for shale gas have been reached. The maximum adsorption gas content of T 3 y7 shale reaches 1 cm 3 /g at 0.5 MPa, and the value of most samples was more than 2 cm 3 /g and, at times, even reached 4.6 cm 3 /g at 5 MPa pressure, which is higher than the main gas shale in the U.S. Organic carbon isotope suggests that the natural gas in T 3 y7 shale is associated with oil-prone and thermally mature gases. According to the simulation product, three stages can be identified in the shale thermal maturation and hydrocarbon expulsion process: the oil window (0.5% < Ro < 1.1%), wet gas window (1.1% < Ro < 1.8%) and the dry gas window (Ro > 1.8%). These results indicate that the natural gas in T 3 y7 shale is characterized as wet gas. The relationship between the gas/oil ratio and the conversion degree of organic matter (TR HI ) was established in this study. Comprehensive analysis of basin evolution, the development of organic-rich shale and burial history, shale gas – shale oil/gas – shale oil – shale gas was regularly distributed from the bottom to the upper strata. Simultaneously, shale oil – wet gas – shale gas developed from the depression center to the basin slope and, subsequently, to the basin margin. In the lake, the zonation of organic types was obvious, which was manifested as Type I-prone in the semi-deep and deep lake while Type III-prone in the shallow lake. The organic matter of target shale was primarily Type-II. The shale gas of T 3 y7 shale was mainly pyrolysis yield, which was most associated with oil, and the wet gas appears broadly. Compared with the marine-continent transition and marine shale, T 3 y7 shale is characterized by a moderate burial depth and thickness, high TOC content, low porosity, high gas content, mostly adsorbed gas and wet gas. [ABSTRACT FROM AUTHOR]

The article focuses on an application concerning the conservation of the usage of the name Plateosaurus Meyer, the first non-English, non-avian dinosaur and the second sauropodomorph and Triassic dinosaur to be named. The proponent of the application requests that International Commission on Zoological Nomenclature use its specific powers to confirm that the generic name Plateosaurus and the name of its type species, P. engelhardti, as both available from Meyer. The proponent also asks the Commission to place on the Official List of Generic Names in Zoology the name Plateosaurus Meyer, and include in the Official List of Specific Names in Zoology the name engelhardti Meyer.

Copyright of Gaea: Journal of Geoscience is the property of Universidade do Vale do Rio dos Sinos 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.)

Copyright of Gaea: Journal of Geoscience is the property of Universidade do Vale do Rio dos Sinos 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.)

Abstract: Large diamond placers have been discovered in a Rhaetian basal horizon (Upper Triassic) in the north of the Sakha Republic (Yakutia) in the drainage areas of the Eekit, Nikabyt, Kelimyar, and Bur Rivers. In typomorphic features the found diamonds and indicator minerals of kimberlites are completely similar to those from Carnian basal horizons but, in contrast to them, are well sorted, and pyropes show features of mechanical wear. Analysis of the geologic evolution of the study area, morphology of diamonds and indicator minerals, and composition of the latter showed that the Rhaetian productive sediments resulted from the erosion of Carnian placers. [Copyright &y& Elsevier]

Copyright of Gaea: Journal of Geoscience is the property of Universidade do Vale do Rio dos Sinos 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.)

Abstract: The formation water of Upper Triassic Xujiahe Formation in the middle Sichuan Basin is of high salinity in most areas and of low to medium salinity locally. All the formation water lack sulphate ion implying good reducing and sealing conditions, but are rich in barium ion. The forming environment of the Xujiahe formation water is similar to that of the Jurassic formation water, but very different from that of the underlying marine formation water. The Xujiahe formation water has lower sodium (potassium) chloride coefficients and higher metamorphism coefficients. The water shows the characteristics of original continental sedimentary formation water reworked by later marine water of high salinity. In reworking the reservoirs, surface water of high sulphate ion content should be avoided, and also quick changes of formation temperature, pressure and chemical equilibrium should be avoided to prevent precipitates from blocking pores and throats. [Copyright &y& Elsevier]