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971.
在龙马溪页岩微观物性特征分析的基础上,综合利用测井解释、微观测试分析资料,建立了一种适用于龙马溪页岩的横观各向同性岩石物理模型,该模型建模过程:将各向异性SCA和DEM模型联合模拟得到的黏土和干酪根混合物作为背景介质;采用SCA模型对脆性矿物混合物进行模拟,利用各向异性DEM将脆性矿物混合物添加到背景介质;进一步将空孔隙添加到页岩基质,并利用Brown-Korringa模型进行各向异性条件下的流体替换,从而得到横观各向同性页岩岩石物理模型.通过对四川盆地A井龙马溪页岩进行岩石物理建模分析,计算了孔隙纵横比、纵横波速、各向异性系数和弹性参数,检验了模型的准确性.研究结果表明:矿物颗粒和孔隙纵横比是影响模型精度的关键参数,黏土和干酪根颗粒纵横比为0.05,图像识别获得的脆性矿物颗粒纵横比主要分布于0.45~1.0(集中分布于0.5~0.85),横波波速反演获得的孔隙纵横比主要分布于0.1~0.3(平均值约为0.22);模型预测和实测纵波波速之间误差为-2.40%~2.21%(平均绝对误差仅1.20%),预测和实测横波波速之间误差为-1.93%~1.42%(平均绝对误差仅0.64%),证实了本文模型的准确性和精度.本文模型能够准确计算页岩5个独立的刚度系数,为页岩弹性参数、声波波速、各向异性和脆性分析提供了有效手段,也为后续地球物理和工程地质参数分析提供了重要依据.
相似文献972.
973.
土层地震反应传递函数的模拟 总被引:5,自引:1,他引:5
探讨了用单一土层模型替换复杂场地求解土层场地传递函数的方法,并用SMART-1台阵地震记录对这一方法的可行性进行了研究和讨论,结果表明,只要选取适当的地震波入射角Ψ和土介质的滞回阻尼比d,简化模型的传递函数与实际传递函数能符合得较好,这一方法可用来近似估计缺少详细土质勘测资料地区的土层地震反应的传递函数。 相似文献
974.
The main purpose of this paper is to introduce a semi‐distributed parallel surface rainfall‐runoff conceptual model. In this paper, a general solution of the instantaneous unit hydrograph (IUH) has been derived successfully for N linearly connected reservoirs, each having a different storage constant. The solution is a function of geomorphologic parameters, meteorologic factors and roughness coefficients. The model also takes into account the hydrologic response which is influenced by outflow downstream of a reservoir. For calibration, the shuffled complex evolution (SCE) algorithm is used to search for the global optimal parameters of the model. Because of the parallel structure, the mean roughness parameter of the channel becomes a “conceptual” parameter without a real physical meaning. To evaluate the adaptability of the model adopted, three watersheds around the city of Taipei in Taiwan were chosen to test the effectiveness of the model. The study provides an appropriate rainfall‐runoff model for planning flood mitigation in Taiwan. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
975.
震源硬化模型的理论、实验及观测事实依据 总被引:7,自引:2,他引:7
从前兆异常共性特征、有关理论分析及岩石实验结果等方面,论证了震源硬化模型的科学性和合理性。 相似文献
976.
977.
Petroleum geological dynamics of Lower Paleozoic in the Ordos Basin, northwest China 总被引:2,自引:0,他引:2
Taking the hydrocarbon source rocks of Ordovician, Lower Paleozoic in the Ordos Basin as the main research object, the characteristics of petroleum geological dynamics about geohistory, geothermal history, hydrocarbon generation history and hydrocarbon expulsion history were studied by using the methods of basin numerical modeling dynamically and pool-forming dynamics. It is shown that the Ordovician strata had entirely undergone five stages of initial deposition, uplift and erosion, rapid subsidence, alternating uplift and subsidence, and differential uplift and erosion; that under the background of lower heat flow on the whole, the paleoheat flow of Ordovician strata in the basin could be divided into two large stages of relatively high heat flow values period before Cretaceous deposition and relatively low ones after it; that the thermal evolution of organic matters in the hydrocarbon source rocks of Ordovician had entered into high mature-postmature stage on the whole and the intensity of gas generated was greater than that of oil generated, the hydrocarbon being mainly natural gas; and that the curves of the intensity of oil and gas expulsion at each time unit showed the feature of multi-peak-type, the accumulative intensity of gas expulsion was greater than that of oil expulsion. Thus natural gas exploration potential is good. 相似文献
978.
D Raptakis F.J Chvez-Garca K Makra K Pitilakis 《Soil Dynamics and Earthquake Engineering》2000,19(1):411
This paper describes the process of construction of the 2D model of Volvi's geological structure and results of empirical and theoretical approaches to the evaluation of site response at Euroseistest. The construction of the 2D model is based on a re-interpretation of the available geophysical and geotechnical data in an effort to improve the definition of the subsoil structure at Euroseistest in terms of the most important parameters needed to model site response. The results of this re-interpretation are compared with a previous published 2D model of the same alluvial valley. Different analysis of the measurements and different criteria in the synthesis of data have led to a different model, even if both studies had access to the same field measurements. This underscores the fact that a model results of an interpretation and is not uniquely determined by the data, no matter how detailed they are. The well known subsoil structure opened the possibility to correlate the geometry and the dynamic properties of the 2D model with the results of site response determined from a detailed analysis of two events in frequency and time domains and 1D numerical modeling. The study of site response shows the important effect of the lateral variations on the ground motion and suggests that the contribution of locally generated surface waves to the resonant peak may be important. In the case of Volvi's graben, the limitations of the 1D approximation to simulate ground motion under complex soil conditions in both frequency and time domains are also shown. This paper lays the ground for a companion article dealing with 2D site effects in this basin. 相似文献
979.
苏鲁交界及南黄海地区地震波速比的变化特征 总被引:2,自引:0,他引:2
本文主要应用多台波速比和单台波速比的方法,计算了苏鲁交界及南黄海(北纬35°35′至36°00′,东经117°00′至121°00′)范围内,1984到1991年7月发生在该区域的163次ML≥1.7地震的波速比值,并对波速比结果进行t检验和模糊数学分析识别。分析结果发现,1985年1月至11月出现了不连续的波速比低值异常时段,模糊数学识别的异常从属函数在这段时间也呈现高值。异常恢复后,1987年 相似文献
980.
通过对山西境内地震序列的分析计算,得出一个适合山西地区地震活动的概率模型。并以此模型对1989年前后的地震活动进行了计算,给出1989年以来山西地震频繁活动的理论依据,对今后的地震活动进行了预测。 相似文献