排序方式： 共有104条查询结果，搜索用时 15 毫秒
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中奥陶统马家沟组为一套海相碳酸盐岩地层.豫北东姚一带马家沟组出露较全，分布稳定，是进行马家沟组层序地层研究的有利地区.在系统研究野外实测剖面的基础上，根据8个岩性段的岩石组合特征、垂向变化规律，在区内马家沟组中识别出2个Ⅰ型层序界面和5个Ⅱ型层序界面，划分出1个二级层序和6个三级层序.通过讨论和分析该区马家沟组各级层序的特征，建立了东姚一带马家沟组的层序地层格架.结合层序地层特征分析，认为区内马家沟组的沉积环境经历了6次海进海退旋回.对区内中奥陶统马家沟组的层序地层研究，可以为研究豫北地区古生代的海平面变化提供参考. 相似文献
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借鉴国外CO2地质储存潜力与适宜性调查评价工作程序,将我国CO2地质储存潜力与适宜性评价工作划分为五个阶段。影响盆地评价阶段CO2地质储存适宜性的因素很多,本文分别从盆地本身物理条件、数据源和资源潜力、地壳稳定性、温度以及经济适宜性五个影响方面形成单因子图,此五类单因子图件的编图基础为中国1∶500万地质图,利用图层属性的加权计算、叠加的成图方法,综合单因子图件形成我国CO2地质储存远景区划图件。 相似文献
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We discussed the possibility of studying crust anisotropy by analyzing azimuthal variation of the receiver functions and presented a technique for computing the transmission response of a flat-layered medium with arbitrarily ori-ented hexagonally symmetric anisotropy using the reflectivity algorithm. Using this method we investigated the crust anisotropy of Taihang Mountain Range (TMR). Our result shows that there is significant anisotropy with a slow symmetry axis in the upper crust and a fast symmetry axis in the lower crust. The anisotropy magnitude of about 8%~15% is found in the upper crust and a smaller magnitude of about 3%~5% in the lower crust. Orienta-tion of the symmetry axes and the depth of anisotropy appearance as deduced from the seismic records of four individual seismic stations are different from each other. The crust anisotropy beneath the four stations may be associated with the local crustal fabrics in a small area. 相似文献
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利用地震走时层析成像方法确定西昌地区断裂带深部几何形态 总被引：1，自引：0，他引：1
断裂深部产状和空间几何关系是研究地壳运动变形、动力作用及其地表响应的基础,也是模拟发震断裂与强震关系的基础。为了研究川西南地区强震活动与安宁河、则木河和金河断裂的关系,对盐源-西昌-雷波高分辨地震折射剖面初至Pg波走时和断层面反射波走时进行模拟,获得了川滇活动地块东边界带安宁河、则木河和金河断裂的深部形态。结果表明:在上地壳内,安宁河断裂和则木河断裂东倾32°～35°,其速度结构为舌状低速带,二者规模较大,延伸到了基底。金河断裂东倾约30°,向下延伸至少5km。 相似文献
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为了增加地下水开采水量,并且尽可能地减小地下水开采后的水位降深,在水源地下游设置地下截水坝,并且同时配合辐射井开采地下水。通过数值模型的计算及预测,截潜流工程不但可以有效地截取地下水径流,更大限度地利用地下水资源,而且可以有效地控制地下水位降深以及腾出地下库容,以便在洪水期容纳更多的洪水入渗。通过实际工程的检验表明:地下截水坝配合辐射井这种截潜流工程在地下水开采中具有重要的作用。 相似文献
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CRUSTAL STRUCTURE FROM YUNXIAN-NINGLANG WIDE-ANGLE SEISMIC REFLECTION AND REFRACTION PROFILE IN NORTHWESTERN YUNNAN,CHINA 
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下载免费PDF全文 The Red River Fault in western Yunnan is one of the longest strike-slip faults in China and has a high seismic potential. To investigate its complicated structure, a near-NS directed 300km long wide-angle reflection/refraction seismic profile was laid out from Yunxian to Ninglang, across the Red River Fault. The 2-D velocity structure model along the profile was obtained through 1-D and 2-D analysis and fitting the observed data with combination of first-arrival traveltime tomography and forward modeling. The results indicate:In the crust, the average P-wave velocity is 6.2~6.3km/s and basically shows a positive gradient structure, but there are some low velocity anomalies at different area in upper and lower crust. Regarding the crust boundary, a relative large lateral variation exists in the depth of Moho, which goes deeper from south to north, ranging from 45km to as deep as 54km; compared to other typical continental crust, the study area demonstrates a striking thickening. It should be mentioned that the crustal thickening is mainly observed in the lower crust, while the upper and middle crust possess nearly constant thickness. We observed strong seismic velocity contrast across the Red River Fault, which emphasizes the role of the fault as an important tectonic boundary between Yangtze paraplatform and Sanjiang geosynclinal system. Along the profile, the Moho depth has no remarkable variation when crossing the Red River Fault. Combining with other study results on nearby area, it proves that there is notable heterogeneity between different parts of the Red River Fault. 相似文献
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