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利用地球物理方法,在钻探前对水合物赋存带进行识别和深度预测,可以为钻探井位的选取及井深的规划提供直接的数据支持.在我国南海北部二维地震数据的基础上,以速度为主要判别依据,以波阻抗反演为佐证,识别水合物赋存带的顶、底界,并以叠加速度谱为基础,预测神狐海域A测线预测井位的水合物赋存深度.在此数据的指导下,经钻探证实,该钻位... 相似文献
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当前,海洋的价值越来越被人类重视,海洋开发活动对于国家发展日益重要,其中海底地形测量在海洋开发中有着举足轻重的地位.相较于应用多波束测深系统或侧扫声呐系统测量海底地形的传统方式,三维侧扫声呐将多波束测深系统与传统侧扫声呐系统的特点融为一体应用于海洋测绘生产,极大地提高了作业效率,减小了作业成本.本文以3DSS-iDX-... 相似文献
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2008年5月12日14时28分汶川发生的8.0级大地震对我国四川省西部及西北部县市造成了特别严重,甚至是毁灭性破坏.基于现场调查资料,分析了彭州灾区的灾害空间分布,描述了典型建筑物破坏和大型滑坡体等地质灾害现象,并结合彭州地区房屋抗震设防情况,对此次地震灾害的主要成因进行了分析.结果表明,本次地震灾害的主要成因包括震级大、破坏力强,滑坡崩塌等地震地质灾害严重,农村建筑物缺乏必要的抗震设防措施等.在未来的规划与建设中,应避开断层、滑坡危险区域,并加强对农村地区建筑物的抗震设防指导. 相似文献
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陕北黄土高原正负地形研究(英文) 总被引:7,自引:1,他引:7
The Loess positive and negative terrains (P-N terrains), which are widely distributed on the Loess Plateau, are discussed
for the first time by introducing its characteristic, demarcation as well as extraction method from high-resolution Digital
Elevation Models. Using 5 m-resolution DEMs as original test data, P-N terrains of 48 geomorphological units in different
parts of Shaanxi Loess Plateau are extracted accurately. Then six indicators for depicting the geomorphologic landscape and
spatial configuration characteristic of P-N terrains are proposed. The spatial distribution rules of these indicators and
the relationship between the P-N terrains and Loess relief are discussed for further understanding of Loess landforms. Finally,
with the integration of P-N terrains and traditional terrain indices, a series of un-supervised classification methods are
applied to make a proper landform classification in northern Shaanxi. Results show that P-N terrains are an effect clue to
reveal energy and substance distribution rules on the Loess Plateau. A continuous change of P-N terrains from south to north
in Shaanxi Loess Plateau shows an obvious spatial difference of Loess landforms and the positive terrain area only accounted
for 60.5% in this region. The P-N terrains participant landform classification method increases validity of the result, especially
in the Loess tableland, Loess tableland-ridge and the Loess low-hill area. This research is significant on the study of Loess
landforms with the Digital Terrains Analysis methods. 相似文献
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本文利用Sellers,W.D.模式的计算结果对随机响应系统的动力过程进行线性化,得到地气系统各纬度带温度随时间变化的随机动力模式,借此模式得到的各个纬度带温度变化主要特征与实际情况基本一致,最后给出了低纬海洋热输送全球效应的模拟试验结果。 相似文献
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Using the CAM3.0 model, we investigated the respective effects of aerosol concentration increasing and decadal variation of global sea surface temperature(SST) around year 1976/77 on the East Asian precipitation in boreal summer. By doubling the concentration of the sulfate aerosol and black carbon aerosol separately and synchronously in East Asia(100-150 °E, 20-50 °N), the climate effects of these aerosols are specifically investigated. The results show that both the decadal SST changing and aerosol concentration increasing could lead to rainfall decreasing in the center of East Asia, but increasing in the regions along southeast coast areas of China. However, the different patterns of rainfall over ocean and lower wind field over Asian continent between aerosol experiments and SST experiments in CAM3.0 indicate the presence of different mechanisms. In the increased aerosol concentration experiments, scattering effect is the main climate effect for both sulfate and black carbon aerosols in the Eastern Asian summer. Especially in the increased sulfate aerosol concentration experiment, the climate scattering effect of aerosol leads to the most significant temperature decreasing, sinking convection anomalies and decreased rainfall in the troposphere over the central part of East Asia. However, in an increased black carbon aerosol concentration experiment, weakened sinking convection anomalies exist at the southerly position. This weakened sinking and its compensating rising convection anomalies in the south lead to the heavy rainfall over southeast coast areas of China. When concentrations of both sulfate and black carbon aerosols increase synchronously, the anomalous rainfall distribution is somewhat like that in the increased black carbon concentration aerosol experiment but with less intensity. 相似文献
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国内大部分高含水油田,注入水窜流现象较为严重,已成为影响油田高效开发的主要矛盾,对窜流通道形成后渗透率场的计算与描述显得尤为迫切和重要。目前窜流通道参数计算方法,只能计算得到注采井点的渗透率数值,不能计算得到注采井间的渗透率分布状况,并且目前窜流通道渗透率计算方法没有将室内实验结果、数值模拟结果和油藏工程方法结果有效结合起来。以国内某高含水油田为例,通过长期注水冲刷实验,模拟了窜流通道的动态形成过程,归纳出了储层岩石注水冲刷倍数与渗透率之间的关系式。在常规数值模拟计算方法的基础上,将渗透率变化规律模型引入到数值模拟计算中,建立了计算窜流通道平面分布的新方法。以海上某油田的地质模型为基础,计算得到了该油田目前状态的窜流通道渗透率平面二维分布规律。综合对比动态数据法、概率密度模型法、经验公式法和示踪剂测试结果,证明本方法得到的结果真实可靠。 相似文献
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针对准零刚度隔振器因结构复杂而难以在有限元模拟过程中实现较好收敛的问题,本文利用ABAQUS软件的多体分析功能,解决了准零刚度隔振器建模分析过程中的简化模拟与收敛性问题,形成了针对准零刚度隔振器性能研究的有限元模拟方法,将模拟结果与实验结果进行了比较,同时分析了参数模拟值与理论值之间的误差,验证了该方法的准确性.针对影... 相似文献