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排序方式: 共有1002条查询结果,搜索用时 171 毫秒
831.
832.
甘谷驿油田长6油层裂缝特征及对注水开发的影响 总被引:1,自引:0,他引:1
甘谷驿油田长6油层为低孔、特低渗透细喉型碎屑岩储层。根据地面相似露头裂缝观测、岩心裂缝描述、镜下薄片裂缝观测、地层倾角裂缝解释及注水开发生产动态表明,长6油层是地面以东西和南北向宏观构造裂缝发育为主、地下主要以东西向为主的微裂缝。这种裂缝在地下大部分呈孤立、闭合状,在现今北东向80°的最大水平主应力背景下,油井压裂投产使东西向微裂缝连通并优先开启,其次为北西向裂缝。南北向微裂缝始终处于挤压状态而闭合,因此,造成油田注水开发注入水沿东西向裂缝油井水串,南北向油井见效差。 相似文献
833.
834.
Sedimentological investigations in Pålamalm, one of the few elongated, flat-topped, raised glaciofluvial deposits of the Stockholm area, show that the deposit was formed in a subglacial tunnel environment during the early Preboreal. The study provides evidence for dynamic links between the morphology of a subglacial conduit, the regional subglacial discharge, and the regional ice-sheet dynamics. The general morphology of the deposit and the lateral esker displacement are parts of a regional pattern.The development and interrelations of the eight distinguished lithofacies at Pålamalm provides evidence for the triggering mechanism responsible for the deposition of this 3-km-long glaciofluvial deposit. Strongly deformed gravels occur close to large dead-ice structures. The occurrence of another elongated and flat-topped glaciofluvial deposit, Jordbromalm, further to the east suggests a sudden regional subglacial outburst (jökulhlaup) in the area. The sudden, intensive enhancement of water discharge in Pålamalm is probably due to the same outburst. This is assumed to have caused the ice roof of the conduit to collapse. The high meltwater-pressure gradient caused the diameter of the conduit to increase rapidly. In addition, the subglacial tunnel took a new route because the original course became blocked by large ice blocks that had fallen from the roof.The steep flanks of the deposit, the presence of large dead-ice depressions along the central part of the deposit and the appearance of two different tunnel-core facies in the main cross-section of the Pålamalm deposit support the hypothesis of a course change after the jökulhlaup. A probable late-glacial crustal rebound in response to the rapid deglaciation in the area may have been the triggering mechanism for the abrupt discharge of the subglacial lake. 相似文献
835.
836.
A. K. Turner A. C. Fabian S. Vaughan J. C. Lee 《Monthly notices of the Royal Astronomical Society》2003,346(3):833-840
We present the analysis and first results from the Reflection Grating Spectrometer (RGS) during the 320-ks XMM–Newton observation of the Seyfert 1 galaxy MCG–6-30-15. The spectrum is marked by a sharp drop in flux at 0.7 keV which has been interpreted by Branduardi-Raymont et al. using RGS spectra from an earlier and shorter observation as the blue wing of a strong relativistic O viii emission line and by Lee et al. using a Chandra spectrum as due to a dusty warm absorber. We find that the drop is well explained by the Fe i L2,3 absorption edges and obtain reasonable fits over the 0.32–1.7 keV band using a multizone, dusty warm absorber model constructed using the photoionization code cloudy . Some residuals remain which could be due to emission from a relativistic disc, but at a much weaker level than from any simple model relying on relativistic emission lines alone. A model based on such emission lines can be made to fit if sufficient (warm) absorption is added, although the line strengths exceed those expected. In order to distinguish further whether the spectral shape is dominated by absorption or emission, we examined the difference spectrum between the highest and lowest flux states of the source. The EPIC pn data indicate that this is a power law in the 3–10 keV band which, if extrapolated to lower energies, reveals the absorption function acting on the intrinsic spectrum, provided that any emission lines do not scale exactly with the continuum. We find that this function matches our dusty warm absorber model well if the power law steepens below 2 keV. The soft X-ray spectrum is therefore dominated by absorption structures, with the equivalent width of any individual emission lines in the residuals being below approximately 30 eV. 相似文献
837.
A.L.Tadross 《中国天文和天体物理学报》2004,4(1):67-74
The present study of the open cluster Collinder 223 (Cr 223) depended greatly on the photoelectric data of Claria and Lapasset. We use the data in conjunction with the AAO/DSS^1 image of the cluster in a re-investigation to improve the main parameters of Cr 223, including the stellar density, the position of the cluster‘s center, the cluster‘s diameter. Its luminosity function, mass function, and total mass are also estimated. 相似文献
838.
冯正全 《成都信息工程学院学报》2004,19(2):189-193
在Windows2000中,用应用程序、服务和驱动器提供的性能数据来评估系统的性能,最简单的方法是用在管理工具中的性能监视器.当我们在编程的时候要用性能数据,必须自己去获取这些数据.通过注册表函数,可以获取我们想要的性能数据. 相似文献
839.
以煤油为溶剂,TBP为萃取剂,研究了CTAB对于Cr(VI)萃取率的影响。结果表明,CTAB能够有效改善Cr(VI)迁移效果,且在一定条件下,可使Cr(VI)萃取率提高到98%,应用于实际电镀废液,回收率在90%以上。 相似文献
840.