提高矿产勘查效果有关问题的探讨     

秦震 《四川地质学报》1992,(4)

本文概述了国内外矿产勘查阶段划分的情况。论证了分阶段进行矿产勘查,可以把勘查费用压缩到工作所必需的程度上,并把那些在工作过程中不应该出现的消耗社会劳动的地质风险和经济风险控制下来。为了提高矿产勘查效果,普查阶段要注意选区,保证原始地质资料质量,有效运用综合技术方法找矿,从实际需要出发研究矿床,并及时对普查的矿床作出选冶试验和技术经济评价。  相似文献   

近地表土壤中油气微渗漏烃的赋存特征及化探指标的实验性研究   总被引：6，自引：6，他引：6  

蒋涛  任春  夏响华 《物探与化探》2003,27(4):251-254

通过对近地表土壤中渗漏烃类气体不同赋存状态的特征分析,结合已知油气藏上方化探指标(顶空气、游离烃、热释烃、酸解烃等)异常的研究,认为这些指标在同一油气藏上方的不同时期的测试含量会有差异,但在各指标异常范围和变化趋势上仍能显示深部油气藏存在的信息,反映出这些指标的有效性、重现性和稳定性,因此,近地表土壤中不同赋存状态的烃类分析可为有效地利用油气化探指标寻找油气藏提供科学依据.  相似文献   

基于历史相似天气评估人工增雨效果   总被引：2，自引：3，他引：2       下载免费PDF全文

耿素江  班显秀袁健 王吉宏 《气象科技》2003,31(4):231-236

文章利用辽宁省1981～1990年10年无人工增雨作业的NCEP 500hPa高度场资料以及1996年、1997年有增雨作业的500hPa资料，对10年间无增雨日及两年中增雨日要素场采用“切比雪夫一傅立叶混合多项式”展开，以寻求两个要素场的最小相关值，藉此给出两年中不同增雨天气型的个例分析及23架次日增雨效果百分率。分析结果表明，在两个要素场达到最小相关值时，一方面两个要素场形势非常相似，另一方面在增雨日播撒区的降水量，大多明显地大于该区历史上非增雨日的降雨量，增雨基本上具有正效果；然而降水一般是由多因素相互作用产生的结果，在统计时也可能出现增雨的负效果或无效果，即“多异性”；但就总体而言，该方法有效地实现了一次增雨效果的评估。  相似文献   

新一代天气雷达在人工增雨中应用的初步研究   总被引：3，自引：1，他引：3  

陈冰张深寿  冯晋勤曾光平  郑淑贞隋平 《应用气象学报》2003,14(Z1):187-192

利用CINRAD配合常规天气分析,对福建省2002年上半年人工增雨作业条件和作业效果进行初步分析.结果表明CINRAD的应用不仅使人工增雨科学性提高,而且为人工增雨效果分析提供一些物理证据.  相似文献   

关于提高金刚石钻进效果的试验研究   总被引：2，自引：0，他引：2  

汤凤林  Н.В.Соловъев 《地球科学》2002,27(5):544-548

为了提高金刚石钻进的效果，根据试验研究结果建议从金刚石镀膜，胎体添加稀土元素2个方面来提高金刚石钻头的工作能力，采用以每转进尺为基础的恒钻速钻进方法，利用泡沫作为冲洗介质的钻进工艺。  相似文献   

一次中小尺度强降水火箭增雨作业效果评估     

王建恒  陈瑞敏  王国宁 《气象科技》2005,(Z1)

分析了2003年7月23夜间至24日,衡水市受副热带高压外围强西南气流及弱冷空气共同作用下出现的一次小尺度强雷雨天气。介绍了实施火箭人工催化增雨作业情况,在作业同时进行了雨量、雨滴谱、雷达和闪电定位观测,利用常规天气图资料、雷达观测资料、闪电定位仪和雨滴谱、雨量等观测资料,对此次天气过程进行了分析,并采用作业区和非作业区对比的方法,就增雨效果从雨量、雨滴谱及秩和检验(Wilcoxon氏法)等方面进行了效果分析,结果显示:在局地强对流云系含水量丰沛,云顶高度高,云层温度低,过冷水区浓厚,同时垂直风切变有利于AgI粒子的结晶和扩散时,作业时机宜选择在降雨初期云中能量聚集尚未释放时,可进一步提高增雨作业效果。  相似文献   

Effectiveness of monsoon floods on the Tapi River, India: role of channel geometry and hydrologic regime     

Vishwas S. Kale  Pramodkumar S. Hire 《Geomorphology》2004,57(3-4):275-291

Geomorphic effects of floods are a function of several controlling factors, such as magnitude, frequency, rate of sediment movement, flood power, duration of effective flows, sequence of events and the channel geometry. In this paper, these measures of effectiveness have been evaluated for the monsoon-dominated, flood-controlled and incised Tapi River, India by defining four flow categories: low flows, moderate flows, floods and large floods. Ratios between effectiveness parameters of moderate flows on one hand and the floods, large floods and maximum floods on the other, were computed to understand the relative importance of moderate and large flows. In addition to this, stream-power graphs for large floods were constructed, and the changes in channel form were analyzed by using multi-date cross-sections. The results of the study indicate that the morphological characteristics of the bedrock as well as the alluvial channels of the monsoonal and incised Tapi River are maintained by large-magnitude, but low frequency floods that occur at long intervals. Because the channel is incised the effectiveness of large flows is accentuated. The incised channel form enhances the role of large floods by reducing the width–depth ratio, and by increasing the velocity as well as the energy per unit area. The low and moderate flows are superior to high-magnitude flows, only in terms of suspended sediment transport and frequency of occurrence. Another conclusion is that the suspended sediment carried by flows may not be the most appropriate criterion for measuring the geomorphic effectiveness of flows, particularly for monsoonal rivers.  相似文献   

内蒙古中东部浅覆盖区化探岩屑测量方法研究及靶区优选应用   总被引：2，自引：2，他引：2       下载免费PDF全文

张 义聂凤军  孙彬彬刘占元  江思宏胡 朋 《中国地质》2005,32(4):696-705

内蒙古自治区中东部二连浩特-东乌珠穆沁旗（东乌旗）一带草原区,地貌景观多为平缓山丘类型.因水系沉积物、风积物以及风化残积物等共存,采样介质的不同将直接影响到地球化学测量效果.在东乌旗的阿太乌拉地区和阿巴嘎旗的莫若格钦两地,对比不同粒度的样品,发现金属矿物微颗粒以物理状态不均匀地混合在岩屑介质内.与小于80目的细粒样品相比,小于4目至大于20目之间粒度的岩屑,化探异常的衬值更大,提取的异常也更准确.采用MapInfo软件提供的IDW插值法成图,得到非常清楚的各种元素之间的空间分布关系,直观地显示出找矿有利地段,对找矿靶区的筛选具有良好的指导意义.笔者通过研究,在工作区内发现几处Cu-Au及Ag-Pb-Zn-Cu异常区,并且初步证实存在带状分布的矿化体,找矿前景良好.实践证明,化探岩屑测量为在浅覆盖地区快速锁定矿产普查范围起到了非常重要的作用.  相似文献   

国内外常规高空观测技术发展近况综述   总被引：1，自引：1，他引：1  

黄炳勋 《气象》1994,20(5):3-9

对国内外高空观测技术在的近几年的进展情况作了综。述及的内容包括：探空仪的各种传感器和电路，各种测风设备，测量精度，自动化与经济有效性等。  相似文献   

Effectiveness of coir-based rolled erosion control systems in reducing sediment transport from hillslopes   总被引：2，自引：0，他引：2  

Ross A. Sutherland  Alan D. Ziegler 《Applied geography (Sevenoaks, England)》2007,27(3-4):150-164

Accelerated soil erosion is ubiquitous on human-modified hillslopes. A variety of erosion control products have been developed to reduce on-site soil resource degradation, and off-site transport of sediment and sediment-associated contaminants to receiving water bodies. However, limited quantitative data are available to assess erosion reduction effectiveness, and to establish the salient properties of the erosion control products. A replicated field-based rainfall simulation study was conducted to compare the runoff and erosion effectiveness of three coir (coconut) fiber rolled erosion control systems (RECSs) with a bare (control) treatment. Detailed temporal measurements of runoff and sediment transport were made during two phases of each experiment: (1) a 110-min application of rainfall via a rainfall simulator at 35 mm h⁻¹ after runoff initiation and (2) a 30-min period, at 3 times the flow rate of phase 1, applied via an overland flow generator. All coir treatments enhanced infiltration, delayed time to runoff generation, reduced intensity of rill incision, and reduced sediment output compared to bare treatments. More importantly, statistically significant differences were observed between coir RECSs of different architecture. For the two open weave coir systems tested, the most effective design had a higher mass per area, and less open space between the regularly aligned grid of fibers. The random fiber coir architecture was the most effective, having significantly lower runoff sediment concentrations, lower sediment yields, and a lower frequency of rill initiation. The differences in system architecture are examined in light of fundamental controls on runoff and erosion processes.  相似文献