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孤岛油田属稠油疏松砂岩油藏,生产过程中油井出砂严重,现有的涂敷砂人工井壁防砂注蒸汽后强度较低,造成防砂成功率低,注汽后高强度采液生产周期较短。为此,通过室内试验,优选出耐高温树脂、高强度骨架颗粒、偶联剂、固化剂,进行室内配方优化试验,评价固结体耐高温性能,测定其渗透率,研制出一种适用于疏松砂岩油藏注蒸汽热采井的HD-1注汽井新型防砂材料。在孤岛油田稠油注蒸汽热采区共试验72口井,成功率为91.0%,截止目前,累计产油为121 572 t,单井平均有效期为233 d。现场应用表明：HD-1注汽井新型防砂材料耐高温、强度高,防砂成功率高,有效期长,能够有效改善注蒸汽热采井的防砂效果。 相似文献
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Lida Xing Martin G. Lockley Dongjie Tang Hendrik Klein Guangzhao Peng Yong Ye Baoqiao Hao 《地学前缘(英文版)》2019,10(1):229-240
The newly discovered large(350 m^2) Yantan dinosaur tracksite, in the Lower Jurassic Ziliujing Formation of Guizhou Province, China, reveals at least 250 footprints of which ~97 can be resolved into trackways of sauropodomorphs. All the trackways are sub parallel likely indicating gregarious behavior. One theropod track(cf. Grallator) was recorded. The sauropodomorph tracks predominantly represent quadrupedal progression(Morphotype A), and footprint morphology is similar to the ichnospecies Liujianpusshunan, characterized by outward pes rotation. Three trackways indicate bipedal progression, and two of these(Morphotype B) indicate inward pes rotation, accompanied by elongate pes digit scratch marks. For the latter phenomenon three possible scenarios are discussed:(1) significant rotation changes accompanying changes in gait,(2) swimming behavior,(3) formation of undertracks.Sedimentological evidence indicates the tracks were made on a linguloid rippled, muddy, immature sandstone substrate characterized by significant differences in substrate consistency across the trackbearing surface. Microbially induced sedimentary structures(MISS) characterized by distinctive wrinkle marks indicate a stressed, probably semi-arid, paleoenvironment that was not conducive to habitation by invertebrate organisms. This is consistent with other evidence that Lower Jurassic sauropodomorph tracks are often associated with semi-arid paleoenvironments. 相似文献
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Abouian Jahromi Mohammad Jamshidi-Zanjani Ahmad Khodadadi Darban Ahmad 《Environmental Earth Sciences》2020,79(14):1-11
Climate change projections indicate an increase in intense rainfall events with consequent river flooding, which could lead to devastating natural disaster 相似文献
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The Nyctosaurus specimen KJ1 was reconstructed under the hypothesis that there is a membrane attached to the crest; the so-called headsail crest. The aerodynamic forces and moment acting on the headsail crest were analyzed. It was shown that KJ1 might adjust the angle of the headsail crest relative to the air current as one way to generate thrust (one of the aerodynamic forces, used to overcome body drag in forward flight) and that the magnitude of the thrust and moment could vary with the gesture angle and the relative location between the aerodynamic center of the headsail crest and body’s center of gravity. Three scenarios were tested for comparison: the crest with membrane attachment, the crest without membrane attachment and the absence of a cranial crest. It was shown that the aerodynamic characteristics (increasing, maintaining and decreasing thrusts and moment) would have almost disappear in flight for the crest without membrane attachment and was non-existent without the cranial crest. It is suggested from aerodynamics evidence alone that Nyctosaurus specimen KJ1 had a membrane attached to the crest and used this reconstructed form for auxiliary flight control. 相似文献
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Structure,Orientation and Finite Element Analysis of the Tail Club of Mamenchisaurus hochuanensis 总被引：2，自引：1，他引：1
Abstract: The structure and orientation of the posterior extremity (tail club) of the caudal vertebrae of Mamenchisaurus hochuanensis Young and Chao, 1972 from the Upper Jurassic Shangshaximiao Formation has been analyzed to determine the tail club function using Finite Element Analysis. Of the four caudal vertebrae composing the tail club, the second largest (C"1") was probably the most proximal, and is fixed with the preceding sequence of the caudal vertebrae, whereas the smallest (C"4") is free and forms the termination of the tail club. Our analysis also suggests that the tail club is more efficient in lateral swinging rather than up-and-down motion, and that the best region for the tail club to impact is at the spine of the largest of the four caudals (C"2"), with a maximum load for impact at about 450 N. The tail club of Mamenchisaurus hochuanensis probably also had limitations as a defense weapon and was more possibly a sensory organ to improve nerve conduction velocity to enhance the capacity for sensory perception of its surroundings. 相似文献
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Majid Dehghani Bahram Saghafian Firoozeh Rivaz Ahmad Khodadadi 《Stochastic Environmental Research and Risk Assessment (SERRA)》2015,29(3):861-874
In this research, a dynamic linear spatio-temporal model (DLSTM) was developed and evaluated for monthly streamflow forecasting. For parameter estimation, coupled expectation–maximization (EM) algorithm and Kalman filter was adopted. This combination enables the model to estimate the state vector and parameters concurrently. Different forecast scenarios including various combinations of upstream stations were considered for downstream station streamflow forecasting. Several statistical criteria, nonparametric and visual tests were used for model evaluation. Results indicated that the spatio-temporal model performed acceptably in almost all scenarios. The dynamic model was able to capitalize on coupled spatial and temporal information provided that there is spatial connectivity in the studied hydrometric stations network. Moreover, threshold level method was used for model evaluation in drought and wet periods. Results indicated that, in validation phase, the model was able to forecast the drought duration and volume deficit/over threshold, although volume deficit/over threshold could not be accurately simulated. 相似文献
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石英在爆裂法测试中常出现α-β峰,此峰是由爆裂温度大于573℃的高温流体包裹体,在α石英相变成β石英时,包裹体发生泄漏（非爆裂）形成的.在金矿地质找矿中,用α-β峰可判断矿脉的剥蚀程度,推测矿床成因 相似文献
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采用改进的热声爆裂仪,测试河北省某金矿的石英,从中发掘出多种成矿找矿信息,主要有: 相似文献
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The Mozduran Formation includes light-coloured, thick-bedded to massive limestone and porous dolomitic limestone and dolomite. In this study, 13 samples from the uppermost Mozduran Formation were taken from two localities and examined for calcareous nannofossils. A total of 19 species and 12 genera were identified in the Mozduran section and19 species and 13 genera for the Taherabad section. Based on these assemblages, the uppermost Mozduran Formation is assignable to Sissingh's (1977) biozone CC1 (Early Berriasian) at the Mozduran section and to biozone CC3 (Late Valanginian) at the Taherabad section. Thus, the formation is younger from east to west across the basin. 相似文献