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The Carboniferous volcanic reservoirs in Junggar Basin contain rich hydrocarbon resources, implying a great exploration potential, so that they have become a key replacement target for "three-dimensional exploration". The study on the Carboniferous volcanic reservoirs and their hydrocarbon accumulation elements is significant for clarifying the orientation for exploration. In this paper, based on 37 reserves reports and 3 200 reservoir test data, the Carboniferous volcanic reservoirs in Junggar Basin were discussed from the prospective of lithology and lithofacies, physical properties, reservoir types, main controls on hydrocarbon accumulation, and hydrocarbon accumulation patterns. It is found that the Carboniferous in the basin is mostly in the multi-island ocean-volcanic island arc structural-sedimentary environment, so it is geologically eligible for forming in-situ volcanic reservoirs. The volcanic rocks are: (1) mostly distributed along deep and large faults, with the lithology and lithofacies controlled by volcanic architectures; (2) dominantly lava, followed by volcaniclastic lava and volcaniclastic rock; (3) distributed in the periphery of hydrocarbon-generating sag and within the source rocks horizontally, and concentrated in the weathering crust at the top longitudinally, possibly leading to reworked weathering crust reservoir; and (4) liable to form inner reservoirs. The volcanic reservoirs can be concluded into four hydrocarbon accumulation patterns, i.e., self-generating & self-storing in paleo-uplift and vertical migration, self-generating & self-storing in paleo-uplift and lateral migration, young-generating & old-storing in fault zone and vertical migration, and young-generating & old-storing in paleo-uplift and lateral migration. Future exploration will focus on the effective source rock development and hydrocarbon supply zones and the self-generating & self-storing and young-generating & old-storing patterns. The exploration prospects are determined to be the Ludong-Wucaiwan-Baijiahai slope belt and the southern slope belt of the Shaqi uplift (self-generating & self-storing pattern) in eastern Junggar, and the fault and nasal arch zone at the northwestern margin and the nasal arch zone (deep and large structure) in the Luxi area (young-generating & old-storing pattern) in western Junggar. [ABSTRACT FROM AUTHOR]

The Triassic formation is a possible new giant hydrocarbon generated formation in Northwest China and Mid-Asia. Taking the Upper Triassic formation in the Sikeshu Sag in Junggar Basin as an example, based on the comprehensive analysis on the geochemical characteristics of the cores and the dark mudstone of the outcrops and reservoir formation conditions, we have evaluated the Upper Triassic source rocks by comparing with those in the Ulungu Depression, and reached the following findings. Firstly, the Upper Triassic formation is mainly composed of dark mudstone and sandy mudstone deposits, and the hydrocarbon source rock is mainly distributed in the middle and upper parts with a thickness range of 100–150 m and area of 3500 km 2 . Secondly, the source rock, moderate in organic matter abundance (with TOC range of 1%–3%), has the material basis for hydrocarbon generation. Thirdly, the organic matter has high percentage of sapropelinite, and is dominated by type II 2 . Fourthly, the degree of the thermal evolution is moderate, and the source rock with R o higher than 0.7% has a distribution area of about 1800 km 2 , providing the conditions of massive hydrocarbon generation. Fifthly, the source rock has great burial depth and wide distribution; the source rock with a R o of higher than 0.7% and thickness of more than 100 m has an area of around 1400 km 2 , implying huge resource potential. Sixthly, the next step exploration should focus on highly mature hydrocarbon generation central area in the Upper Triassic - Lower Jurassic in the east of the sag to search for and confirm favorable traps. The research findings have important reference value for promoting the resource status of, deepening the understanding of reservoir formation, and clarifying the exploration direction in the Sikeshu Sag and other periphery Mid-Asia areas. [ABSTRACT FROM AUTHOR]

The Bulonggoer paleo-oil reservoir (BPR) on the northwest Junggar Basin is the first Devonian paleo-oil reservoir discovered in North Xinjiang, China. Solid bitumens occur within sandstone pores and as veins filling fractures. Samples of both types were analyzed using stable carbon isotope and reflectance measurements, as well as molecular biomarker parameters. The extremely positive δ 13 C values and biomarker indicators of depositional environment/lithology, such as pristane/phytane (Pr/Ph), C 29 /C 30 hopane, diasteranes/regular steranes and dibenzothiophene/phenanthrene ratios, indicate a siliciclastic source for the BPR and their deposition in a highly reducing hypersaline environment. The presence of long chain n -alkanes and abundant tetracyclic diterpanes, C 20 –C 21 tricyclic terpanes and perylene are indicators of higher plant organic matter input. Moreover, the bimodal distribution of C 27 > C 28 < C 29 regular steranes and abundant methyltriaromatic steroids also support a contribution of microalgae as well as higher plants organic matter. The similar molecular composition and thermal maturity parameters indicate that the reservoir and veined solid bitumens were altered from a common paleo-petroleum, which originated from peak oil window matured source rocks. All solid bitumens from the BPR are characterized by relatively low bitumen reflectance values (Rb% < 0.7), suggesting that they were generated from low temperature processes rather than oil thermal cracking. Comparatively, the Rb% values for veined bitumens are higher than reservoir bitumens, indicating that the veined bitumens occurred earlier and experienced higher thermal conditions. [ABSTRACT FROM AUTHOR]

Duck virus enteritis (DVE) is an acute and contagious herpes virus infection of duck, geese and swans with high morbidity and mortality. The development of specific mucosal immune system against duck enteritis virus (DEV) infection for ducks has been hindered by a lack of knowledge concerning the purification of immunoglobulin A (IgA) of duck. In the present work, the method for purification of duck immunoglobulin A was developed, and the induction of intestinal mucosal immune responses against DEV was studied by orally infected ducklings with virulent DEV. The results showed that a continuous increased DEV DNA levels were observed in blood and various organs examined of orally infected ducklings throughout the infection, which was accompanied by the development of infection in ducklings from mild progressed to severe pathological lesions. Furthermore, a marked increased level of DEV-specific IgA and IgG antibodies in bile, serum and the intestinal tract, as well as the density of IgA(+) cells in intestine were detected between 1 and 12days p.i., followed by a drastic reduction of the antibody levels and the density of IgA(+) cells at 15days p.i. The results indicate that the DVE infection can stimulate both IgA-dominated antibody immune responses in the intestinal tract, and IgG-dominated antibody systemic immunity in the serum of ducklings orally inoculated with virulent DEV. The severe lesions of the villus epithelial cells and the lymphoid organs can suppress the intestinal mucosal immune responses.