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51.
溃屈型滑坡滑动面切层段对稳定性的影响研究 总被引:1,自引:1,他引:0
在溃有坡滑动面顺层和切层段强度参数关联性研究的基础上,进一步研究发现,切层段滑动面的长度、角度变化,对滑坡稳定性有明显的影响,这种变化,对滑坡稳定性评价及滑坡的工程治理意义较大。 相似文献
52.
对1900~2002年全球记录到的震级M≥4.0地震震中,利用IGRF(国际地球参考场)国际参考模型确定地磁场的特征。研究了主要地震活动带的地理学和内源引发的基本地磁场几何学之间的关系,查明了不同构造类型的地震活动带全球分布与地磁偏角或地磁场东-西向分量分布之间的构造对应。 相似文献
53.
Spatio-temporal variation of transition probability of bursting events over the ripples at the bed of open channel 总被引:2,自引:1,他引:1
Saeed Jafari Mianaei Ali Reza Keshavarzi 《Stochastic Environmental Research and Risk Assessment (SERRA)》2008,22(2):257-264
In this study, the turbulent flow structure over the ripples at the bed of open channel was investigated experimentally. An
analysis of bursting process was used to recognize the susceptible regions for sediment entrainment and deposition over the
ripples. Two artificial ripples were built according to the ripples, formed by nature. Three different configurations of ripples
were used by changing the wavelength. According to analysis of bursting event it was found that at the stoss side of ripples,
quadrants (II) and (IV) were dominant to the quadrants (I) and (III) and at the lee side of the ripple it was vice versa.
Also the transition probabilities of the bursting events were determined. The results showed that stable organizations of
each class of the events had highest transition probabilities whereas cross organizations had lowest transition probabilities.
Additionally, an effort was made to find the average inclination angle of the bursting events in quadrants (II) and (IV).
The results showed that the mean angle of events in quadrants (II) and (IV) increases at the downstream of stoss side to the
crest in each experimental test. Also, at the lee side where the sediment particles were deposited, the inclination angles
had the highest values. 相似文献
54.
转换波偏移可以利用纵横波波场信息,得到高分辨率的成像结果,从而为油藏描述提供高质量的地震资料.目前的研究主要是利用纵波波场信息进行偏移成像,然而,传统的纵波方法在复杂探区成像时具有一定的局限性.为此,本文在各向异性介质声波射线追踪算法的基础上,推导出各向异性介质转换波射线追踪方程,发展了一种转换波射线追踪算法;并将研究的追踪算法应用到偏移成像中,提出了一种各向异性VTI介质角度域转换波高斯束偏移成像方法.通过各向异性VTI介质断块模型和复杂构造模型试算,说明了本文方法的正确性和有效性.模型试算的结果表明,在考虑地下各向异性时,本文研究的方法具有更好的成像效果,提取的角道集结果可以为偏移速度分析提供依据. 相似文献
55.
工业界计算孔隙压力系数普遍应用的Eaton和Fillippone方法都需要构建能够准确表征低速层的层速度模型,层速度模型精度及效率成为制约孔隙压力预测的关键参数,但目前工业界层速度建模的精度及效率很难满足孔隙压力预测的要求.本文由正常压实情况下的背景速度场出发,基于时距曲线公式及角道集抽取公式,创新推导了以角度域共成像点道集(ADCIGS)剩余曲率为自变量的孔隙压力系数计算公式,该公式完全由去噪后的地震数据进行驱动,不需要构建层速度模型,该方法大幅提高了计算孔隙压力系数的效率.由模型测试及实际数据应用证明,利用本文提出方法进行孔隙压力预测是有效可行的,该方法可以有效提高预测孔隙压力精度,还可以有效提高预测孔隙压力效率. 相似文献
56.
57.
This study presents shear wave splitting analysis results observed at ISP (Isparta) broadband station in the Isparta Angle,
southwestern Turkey. We selected 21 good quality seismic events out of nearly 357 earthquakes and calculated splitting parameters
(polarization direction of fast wave, ϕ and delay time between fast and slow waves, δt) from mainly SKS and a few SKKS phases of the selected 21 seismic events. Then, we compared calculated splitting parameters
at ISP station (56° ≤ ϕ ≤ 205°; 0.37 s ≤ δt ≤ 4 s) with those previously calculated at ANTO (Ankara) and ISK (İstanbul) stations (27° ≤ ϕ ≤ 59°; 0.6 s ≤ δt ≤ 2.4 s and 26° ≤ ϕ ≤ 54°; 0.6 s ≤ δt ≤ 1.5 s) which are located at 230 and 379 km away from ISP station in central and northwestern Turkey, respectively. The
backazimuthal variations of the splitting parameters at ISP station indicate a different and complex mantle polarization anisotropy
for the Isparta Angle in southwestern Turkey compared to those obtained for Ankara and İstanbul stations. 相似文献
58.
对海洋多糖类药物—“872”样品,采用乙醇沉淀分级法得到的5个不同分子量级份(Ⅰ~Ⅴ)。以粘度法测定5个级份特性粘数[η];用激光小角光散射仪(LALLS仪)测定了各级份的重均分子量M_w和第二维利系数A_2;标定出“872”样品的Mark Houwink公式。测得872样品各级份/特性粘数。 相似文献
59.
A method for estimating the gear shape of a mid-water trawl 总被引:2,自引:0,他引:2
60.
Erman Özsayın 《Geodinamica Acta》2016,28(4):241-253
Western Anatolia is one of the world’s most seismically active regions. A nearly N–S-oriented extension caused the formation of E–W- and NE–SW-trending major grabens, creating the potential for earthquakes with magnitudes ≥ 5. The fault segments of the NE-trending Çameli Basin were evaluated using geomorphic indices, common tools for assessment of relative tectonic activity in such areas. Quantitative measurement of geomorphic indices including mountain-front sinuosity (Smf; 1.35–2.39), valley floor width-to-height ratios (Vf; 0.08?0.37), and hypsometric integral (HI; 0.31–1.05) suggest relatively higher tectonic activity along western and southern part of the basin. Hypsometric curves for all segments of the faults mostly exhibit concave or straight profiles, signifying existence of young mountain fronts in the Çameli Basin. These calculations indicate that the Çameli Basin is tectonically active and, southern/south-western areas of this depression have earthquake potential, consistent with epicentres of recent earthquakes, occurred along some fault segments. Possible reason of this activity seems to be related to the E–W-trending corridor lying between the Gulf of Gökova and south-eastern part of the Çameli Basin, represented by active normal faults. These findings should be valid beyond the Çameli Basin for similar situations along the Isparta Angle’s western margin. 相似文献