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1.
文中运用损伤力学研究方法 ,提出孕震过程中引起地壳破坏的应力 -损伤耦合效应。利用应变等效性假设 ,推导了地壳体的应力 -损伤耦合效应与地表重力变化之间的理论关系。根据岩石力学实验的不同加载途径 ,模拟了 1976年唐山 7 8级地震和 2 0 0 1年昆仑山口西 8 1级地震重力演化的不同特征 ,结果与实际情况符合较好 ,表明应力 -损伤耦合效应可以作为地震前地壳重力变化的一种物理解释  相似文献   
2.
城乡一体化地籍建设的研究与探讨   总被引:1,自引:0,他引:1  
本文介绍了现行地籍基础业务体系,在分析其存在的问题的基础上,提出了城乡一体化地籍建设的解决方案,并对建设目标、任务、内容进行了初步的研究与探讨.  相似文献   
3.
In this paper, we report a rare reflection effect eclipsing sdB+dM binary, 2M?1533+3759. It is the seventh eclipsing sdB+dM binary that has been discovered to date. This system has an orbital period of 0.16177042 day and a velocity semi-amplitude of 71.1 km?s?1. Using a grid of zero-metallicity NLTE model atmospheres, we derived T eff=29250 K, log?g=5.58 and [He/H]=?2.37 from spectra taken near the reflection effection minimum. Lightcurve modeling resulted in a system mass ratio of 0.301 and an orbital inclination angle of 86.6°. The derived primary mass for 2M?1533+3759, 0.376±0.055 M , is significantly lower than the canonical mass (0.48 M ) found for most previously investigated sdB stars. This implies an initial progenitor mass >1.8 M , at least a main sequence A star and perhaps even one massive enough to undergo non-degenerate helium ignition.  相似文献   
4.
We present a multitransition study in the 13CO(1-0), 12CO(2-1), 12CO(3-2) and 12CO(4-3) lines of a parsec scale elongated structure connected to a low-mass dense core. Densities larger than n H 2 = 104 cm?3 are inferred in the central regions of this structure, supporting the proposition that it is a genuine filament denser than its environment. The sharp observed drop of the 12CO and 13CO emissions requires a power law density fall-off steeper than r ?1 although a single density law cannot reproduce the spatial shift of 0.1 pc between the 13CO and 12CO drops. Our results support the previous proposition that this elongated structure is a filament threaded by helical magnetic fields, channeling the gas inflow onto the dense core.  相似文献   
5.
据KCl含量的概率分布特征,晶间卤水分为7个总体。晶间卤水KCl,在三级系统内水平分异有2种、剖面分异有5种,二级系统内水平分异呈环带状、剖面分异形式为三级系统内分异形式的组合,垂直分异有13种;富集的总体为Ⅳ(kcl)、Ⅲ(kcl)用V(kcl)、三级系统为(8)和(10)号、部位为固相钾高含处;分异及富集的成因主要为晶间卤水的阶段性淡化。  相似文献   
6.
部分中国近海湖盆和大西洋裂谷盆地发现了腐泥型有机质碳同位素偏重的现象,并伴随异常高总有机碳含量和生烃潜力。本文依据泥岩有机碳测试、孢粉分析、主微量元素、泥岩和原油碳同位素及饱和烃色质色谱资料,并结合现代湖泊盘星藻发育特征,从有机质来源、古环境条件和有机质保存改造三个方面探讨了珠江口盆地珠三坳陷古近系文昌组碳同位素正偏移的成因机制。珠三坳陷文昌组碳同位素异常与气候、古生产力、古水深和藻类勃发等古环境因素有关。然而,从三级层序尺度看,古水深可能是一个不可忽视的重要因素:指示水深的Rb/K比值随深度加深而增加,与碳同位素和TOC含量变化趋势一致。同时现代湖泊研究也证实了盘星藻分布于不同水深范围,因此“深水型盘星藻”的繁盛很可能是珠三坳陷文昌组二段烃源岩碳同位素偏重的根本原因。  相似文献   
7.
根据2015年10月份开展的水质监测结果,采用综合污染指数、有机污染指数和富营养化指数对秦皇岛主要入海河口的水质状况进行分析评价。结果显示:秦皇岛市入海河口的首要污染物为DIN、DIP;大蒲河口、汤河口和新开河口的有机污染较为严重;大蒲河口、汤河口和洋河口处于重度富营养状态,其次为戴河口、新开河口和石河口。建议对入海污染物进行严格的总量控制,加强对港口、船舶的环境污染监管,从而进一步改善近岸海域的生态环境。  相似文献   
8.
Continental epithermal ore deposits are commonly associated with sedimentary organic matter, oils or solid bitumen. These organics embedded in mineral deposits can convey valuable information of the ore genesis. However, the extent to which the formation of ore minerals was recorded by organic compounds remains largely unknown, as also is how metal-rich ores interfere with the molecular proxies in the temperature regime envisaged for hydrothermal activity. The molecular compositional changes of ...  相似文献   
9.
Crustal structures of Japan were investigated under the Upper Mantle Project in three profiles, Kurayosi-Hanabusa, western Japan; Atumi-Noto, central Japan; Kesennuma-Oga, northeastern Japan. These investigations have revealed that the crust of Japan is of continental type. The variation of the crustal structure reflects the topography, especially the water depth; so the thinning of the crust occurs near the shore where the water depth increases rapidly. The velocity below the Mohorovi?i? discontinuity is smaller than 8.0 km/sec, but it is possible that a deeper layer with a velocity of over 8.0 km/sec may exist. The basaltic layer in central Japan, if existing at all, must be thin.  相似文献   
10.
We report on the outcome of the first major multi-site campaign on a long-period variable subdwarf B star. The target PG 1627+017 was observed for a total of 334 h during April/May/June 2003 from the lynchpin observatory at Mt. Bigelow, Arizona, with important contributions coming from co-observations at SAAO, Calar Alto and Siding Spring. Preliminary analysis indicates the presence of 8–10 probable periods in the range ~4500 to ~8900 s with relative amplitudes between 0.1 and 0.5%;. The range over which the periods are found is in qualitative agreement with theoretical predictions and the number of periods found shows potential for an in-depth asteroseismological analysis. Multi-colour observations show that the relative amplitudes of pulsation are larger in the U-band than in the R, which again is in agreement with theory. However, more multi-colour observations are needed to be able to make statements at the quantitative level.  相似文献   
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