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1.
泌阳凹陷核桃园组微量元素演化特征及其古气候意义   总被引:31,自引:6,他引:31  
泌阳凹陷下第三系核桃园组总体上表现为一个大的湖退体系,而其中的微量元素含量及有关元素比值却呈现出细微而明显的旋回变化特征。本文依据泥岩、页岩和碳酸盐岩中Ti、Sr、Ba等十六种微量元素含量及Sr/Ba、Fe/Mn、Sr/Cu等七种比值的变化特征,结合古盐度及岩相资料,对核桃园组沉积时的古气候作了系统的研究,基本上分出了温暖潮湿、干湿交替、炎热干旱、温热半干旱四类较为特征的古气候类型,以期为油气勘探提供依据。  相似文献   
2.
Gas outburst disasters are becoming more serious as the underground coal mines become deeper in China, and a thick zone of deformed coal provides conditions favorable to coal and gas outbursts. The Daning coal mine’s main mining seam is the No. 3 coal seam with coal and gas outburst hazard, which often contains two normal coal sub-layers and one deformed sub-layer. Considering both the geological conditions of the coal seam and applications of the in-seam directional longhole drilling technology, a new schematic diagram of in-seam directional longholes for gas drainage is developed. The two borehole layout models of longwall panel and main entries for gas outburst disasters control have been successfully applied. The gas drainage rates of both models are >70 %, and the residual gas contents are both <8 m3/t, which can be considered that the gas outburst disasters were effectively controlled. To better guide gas drainage, gas drainage normal and failure modes have been obtained. Although in-seam directional longhole technology has been successfully applied for regional gas drainage with benefits to gas outburst control, there are also some problems that are detrimental to greenhouse gas reductions in gas drainage and gas utilization. The three main problems are air leakage failure in gas drainage, decreasing gas concentration and a low gas utilization ratio. To address the problems mentioned above, five improvements are suggested.  相似文献   
3.
介绍了地震信息反馈系统的原理和功能,给出了系统的结构框图,对发送终端和接收终端的功能做了具体描述。在应用上也做了具体阐述,该系统能有效、快速地传送地震三要素信息。  相似文献   
4.
广东省"十五"项目测震台站台址勘选结果分析   总被引:2,自引:0,他引:2  
利用地震台址勘选过程中产出的地脉动背景噪声数字记录,计算勘选出的各台站背景噪声地脉动速度均方根值(RMS)、噪声功率谱密度等数据.成果在于得出各地震台站的背景噪声水平和等级分类,为将来计算各地震台站的场地响应及震级修正值等测震学研究提供基础资料,是对"广东省数字地震观测网络"项目测震台站勘选工作的总结与评价.  相似文献   
5.
介绍广东数字遥测地震台网自投入正式观测运行以来,在进行台网系统运行维护、台网规范管理和开展地震科研工作等方面所做的一些探索和取得的一些经验。  相似文献   
6.
宽频带地震计的安装   总被引:1,自引:1,他引:0  
简要介绍了地震噪声的一些特点、环境因素影响宽频带地震计产生噪声的机制,并针对这些特点介绍了安装宽频带地震计的一些隔热保护方法和需要注意的事项,最后从检验系统安装与运行状况的角度,介绍了地震计的标定和台站噪声检测问题,列举了作者在宽频带测震台站建设中的工作实例.  相似文献   
7.
In the Yangliu Mine in Huaibei Coalfield, violent magma intrusion produced two layers of the igneous cover sills and the annular dike and caused the ejection of gas and water in the bed splitting from the surface well that destroyed the gas extraction system on the surface. The source, flow characteristics and hazard of the gas in bed splitting under igneous sills were researched via laboratory experiments, theoretical analyses and numerical simulations. The experimental results indicate that the shorter the distance from the igneous sill and the larger the thickness of the igneous sill, the greater will be the amount of the thermal evolution, the pyrolysis stoma, the coal adsorption and desorption ability and the risk of outburst, six coal samples collected at different distances from the igneous sill. The first breaking length of the igneous sill, the volume of the bed splitting, the gas pressure and flow rate in the bed splitting and the accumulative volume of the gas ejected from the surface well #2 were theoretically calculated. The laws of the bed splitting development under the igneous sills were simulated, consistent with the theoretical calculation results. The regional control and prevention technologies for coal seam gas under igneous sills were proposed and applied. Then the safety of the first-mining seam production and the gas extraction in the adjacent seam and bed splitting via the surface well was ensured, and no accidental gas and water ejection occurred.  相似文献   
8.
Geotechnical and Geological Engineering - Uniaxial compressive strength is an important mechanical parameter for rock mass engineering. Hence, how to determine the UCS simply and accurately have...  相似文献   
9.
中国龙虾叶状幼体营养初步试验   总被引:6,自引:0,他引:6  
韦受庆  赖彬 《海洋通报》2000,19(2):36-41
通过多次对比重复试验,对用对虾液汁培育金藻Dicrateiasp、扁藻Plalymomassp,用金藻、扁藻培育丰年虫Arlemia salina幼体和毛蚶Scapharca subcrenata,以及用金藻扁藻、丰年虫投喂中国龙虾Panu欤椋颍酰? stimpsoni早期叶状幼体进行了探讨。结果表明,叶状幼体进入第Ⅲ 期后交替掺喂毛蚶卵巢刀额新对虾Metapenaeusensis肉,取得较好的培育  相似文献   
10.
针对传统的三维建模方法存在周期长、效率低等缺点,提出基于CityEngine和SketchUp的快速建模方法.首先通过ArcGIS对遥感图像进行矢量化,然后通过计算机生成的建筑模型(Computer Genera-ted Architecture,CGA)规则快速构建三维模型,并结合SketchUp进行标志性建筑物模型...  相似文献   
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