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71.
为了寻求解决辽河盆地杜229断块超稠油油藏在开采过程中水侵严重影响生产的问题,通过研究该区块构造演化史,分析了断层在超稠油成藏过程中的作用,认为该区块的边界断层对油气成藏起侧向封堵作用,后期小断层使油藏复杂化。根据水性分析和示踪剂监测资料,推断水侵的主要原因是部分断层的不封闭。建议在以后超稠油开发生产中,生产井段要距不封闭断层70 m以上。  相似文献   
72.
本文提出了一种唇口斜置,唇部带双回流的新型船舶尾轴密封环,并介绍了这种环的结构原理、理论分析和设计方法。  相似文献   
73.
Environmental exposure to metals is believed to affect marine mammal health adversely including immunosuppression or acute as well as chronic inflammatory processes leading to hypersensitivities or autoimmune diseases. Metal-specific hypersensitivities were found in several pinnipeds of the North Sea. However, hypersensitivity is a complex phenomenon whose characteristics are still not completely understood; in particular, effects on health are not well established. In the present study, we compared basic hematological and biochemical parameters of seals with and without metal-specific hypersensitivities. We found altered hematological parameters and liver enzyme patterns in seals with a metal-induced hypersensitivity, including a reduction in macrophages, an increase in lymphocytes, and elevated levels of lactate dehydrogenase. These findings support the suggestion of a chronic influence of metal pollutants on the health of marine mammals of the North Sea.  相似文献   
74.
In Cambrian Mesón Group, NW Argentina, small faults and three opening-mode fracture sets defined by orientation and cement texture (Sets 1–3) formed sequentially in sandstone that most likely had constant mechanical properties throughout deformation. Yet the opening-mode sets display contrasting fracture-aperture-size distributions, spacing patterns, and tendency to be bed bounded. Set 1 fractures are quartz-filled or -lined opening-mode fractures with crack-seal texture, having a wide range of opening-displacement (kinematic aperture) sizes; they are irregularly spaced and non-strata-bounded fractures. Set 1 macro and microfracture-opening-displacement sizes are well described by a power law with slope −0.8. Set 2 fractures are microscopic, mostly quartz filled and have characteristic aperture sizes, are probably not bed bounded and have either a near-random or clustered spatial distribution. Set 3 fractures are quartz-lined, opening-mode fractures with extensive open pore space, having a narrow (characteristic) opening-displacement size distribution; they are regularly spaced and stratabounded. Differences between Sets 1 and 3 can be accounted for by quartz deposition resisting fracture reopening to a greater extent for Set 1 during repeated, episodic growth, where crack-seal texture is present in fracture-spanning quartz. In contrast Set 3 fractures are nearly barren with only trace-cement deposits that did not resist opening. Power-law opening-displacement size distributions may be favored in cases where fracture growth is unequally partitioned amongst variably cemented fractures, whereas a characteristic size is favored where growth is unaffected by cementation. Results imply that thermal history and diagenesis are important for fracture-size-distribution patterning.  相似文献   
75.
76.
浅析山洞数字形变观测手段的干扰途径及解决方法   总被引:1,自引:0,他引:1  
本文分析了影响丹东地震台洞室形变仪器观测精度的各种外界干扰因素,提出了解决干扰的措施办法,希望能为同行提供参考。  相似文献   
77.
An analytic investigation of the effect of surface seal mechanical properties, overland flow, and subsurface hydrology was performed on headcut development. Headcut growth rates on upland areas have been observed to be quite small (less than 0.00015 meter per second) and that they occur in increments in which chips break off at points where cracks have developed in surface seals. The substrate soil under the seal collapses and is removed by the flow. This mode of headcut development is the result of a strong interaction between the surface and the subsurface processes. The surface process is energetically controlled by the mechanical features of the seal whereas the subsurface process is hydrologically controlled. The analysis yields estimates of the temporal scale of headcut velocities. In cases of infiltration from the vertical gully wall into the substrate, the flexural wave velocity (seismic sound velocity) was found to inversely affect headcut velocity.  相似文献   
78.
Subantarctic fur seals (Arctocephalus tropicalis) appear as stragglers on New Zealand coasts. Four records are noted, the most recent at Antipodes Island in December 1989.  相似文献   
79.
The recently deglaciated environments in maritime permafrost regions are usually affected by very active paraglacial processes. Elephant Point is an ice‐free area of 1.16 km2 located in the SW of Livingston island (South Shetland Islands, Antarctica). Between 1956–2010 the retreat of the ice cap covering most part of this island has exposed 17.3% of the land surface in this peninsula. Two geomorphological units were identified in this new ice‐free area: a moraine extending from the western to the eastern coastlines and a relatively flat proglacial surface. The glacier in 1956 sat in contact with the northern slope of the moraine, but its accelerated retreat ‐ in parallel to the warming trend recorded in the Antarctic Peninsula ‐ left these areas free of glacier ice. Subsequently, the postglacial evolution was controlled by the relaxation phase typical of paraglacial systems. The typology and intensity of geomorphological processes show a significantly different dynamics between the southern and northern slopes of the moraine. This pattern is related to the different stage of paraglacial adjustment in both slopes. In the southern side, on coarser sediments, pronival ramparts, debris flows and alluvial fans are distributed, with a low to moderate activity of slope processes. In the northern side, mass wasting processes are extremely active on fine‐grained unconsolidated sediments. Ice‐rich permafrost is being degraded by thermokarst processes. Landslides and mudflows transfer large amounts of sediments down‐slope. The surface affected by retrogressive‐thaw slumps in the moraine has been quantified in 24,172 m2, which accounts for 9.6% of its surface. The abundance of kettle‐lakes is also indicative of the degradation of the ground ice. Paraglacial processes are expected to continue in the moraine and proglacial area in the near future, although their intensity and duration will depend on the magnitude and rate of future climate trends in the northern Antarctic Peninsula. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
80.
脱杆现象常常会中断宝石的加工过程,是影响中国宝石加工企业生产效率与产品质量的主要因素之一。通过分析火漆胶粘结宝石的原理与脱杆原因后认为,在宝石的加工过程中,改善工艺操作及相应的工艺材料、规范操作要领可有效地降低宝石的脱杆率,对宝石的加工与生产有一定的现实指导意义。  相似文献   
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