柴达木盆地西部西岔沟剖面湖相碳酸盐岩岩石学特征与沉积环境分析   总被引：3，自引：0，他引：3       下载免费PDF全文

宋华颖伊海生  范爱春马 雪 孙 瑕 《中国地质》2010,37(1):117-126

湖相碳酸盐岩在柴达木盆地西部古、新近系地层中广泛出露,在研究区西岔沟地区主要分布在下干柴沟组、上干柴沟组的顶部,下油砂山组及上油砂山组的底部。通过实测西岔沟剖面、岩性分析、岩相组合特征、生物特征、沉积构造、室内薄片鉴定等研究对西岔沟剖面的碳酸盐岩进行了分析,识别出西岔沟剖面的碳酸盐岩的类型主要有鲕粒灰岩、介壳灰岩、藻叠层石灰岩、泥晶灰岩、砂质灰岩等,沉积环境主要属滨浅湖,并在岩石学特征的基础上对其成因进行了研究。  相似文献   

A physical explanation of solar microwave Zebra pattern with the current-carrying plasma loop model     

Baolin Tan 《Astrophysics and Space Science》2010,325(2):251-257

The microwave Zebra pattern structure is an intriguing fine structure on the dynamic spectra of solar type IV radio bursts. Up to now, there is no perfect physical model for the origin of the solar microwave Zebra pattern. Recently, Ledenev et al. (Sol. Phys. 233:129, 2006) put forward an interference mechanism to explain the features of microwave Zebra patterns in solar continuum events. This model needs a structure with a multitude of discrete narrow-band sources of small size. Based on the model of a current-carrying plasma loop and the theory of tearing-mode instability, we propose that the above structure does exist and may provide the main conditions for the interference mechanism. With this model, we may explain the frequency upper limit, the formation of the parallel and equidistant stripes, the superfine structure and intermediate frequency drift rate of the Zebra stripes. If this explanation is valid, the Zebra pattern structures can reveal some information of the motion and the inner structures of the coronal plasma loops.  相似文献   

Collision criterion for two satellites on Keplerian orbits     

Dan Xue  Junfeng Li 《Celestial Mechanics and Dynamical Astronomy》2010,108(3):233-244

This paper analyzes the collision possibility for two satellites on Keplerian orbits. Coplanar and noncoplanar cases are considered, respectively. For each case, the problem of collision possibility analysis can be solved through two steps: First, to determine whether there is any intersection point of the two orbits; if there is no intersection point, the conclusion can be given directly that collision never happens. Secondly, if the two orbits do intersect, the collision possibility in the given time-scale can be studied in terms of the relationship between the two orbital periods and time. Numerical simulations for both cases, each including several situations, are given to prove the validity of the proposed collision criterion.  相似文献   

基于Altera IP核的RS译码器的设计与实现   总被引：1，自引：0，他引：1  

刘学  苏建峰  孙婷 《时间频率学报》2010,33(1):28-31

介绍了一种基于Altera公司提供的Reed-Solomon IP（intellectual property）核来实现RS译码功能的设计方法,该方法具有开发周期短、系统成本低以及稳定可靠特点。主要分析了Altera公司提供的IP核工作原理、参数配置以及接口设计,最后通过时序仿真验证了该设计的正确性。该设计方法已经成功应用于BPL长波接收机数据解调模块中。  相似文献   

沙嘴海岸地形对黄河三角洲沿岸余流场的影响   总被引：1，自引：1，他引：0  

薛兴华  李国胜  王海龙 《第四纪研究》2010,30(5)

以钓口流路时期1967年前后的海岸地形为例,研究了沙嘴海岸地形对黄河三角洲沿岸余流场的影响.数值对比试验表明,沙嘴附近的余流流向受地形扰动而不断偏转,使得沙嘴地形特征可能引起局部余环流结构的改变,甚至在沙嘴附近呈现出小的涡环结构,沙嘴对流向的影响随离沙嘴地形距离的增加而渐弱.沙嘴海岸地形还将引起局部流速的增加,并在其附近海域形成高流速区,在忽略沙嘴地形的条件下,一些随沙嘴而生的高流速区范围缩小、流速降低,并向西南移动,甚至消失,原沙嘴前沿余流流速明显减小,随离沙嘴距离的增加,流速差异逐渐微弱.  相似文献   

遥感影像三维可视化的实现及应用初探     

杨雪  秦岩宾  谢洪斌 《四川地质学报》2010,30(4):478-481

三维可视化是众多GIS应用中的重要组成部分。本文就如何利用地形图和遥感图像等多源数据实现三维可视化的技术路线及相关原理作了详尽阐述并对其在地质中的应用做了初步探究,对野外地质区调工作部署有一定的辅助指导意义。  相似文献   

矿床学研究思路的变化与进展综述          下载免费PDF全文

罗雪  曹新志 《地质找矿论丛》2010,25(2):147-152

矿床学的发展突破在很大程度上取决于其研究思路的发展变化上。矿床学从传统的对单一矿种、单一矿床和单一成矿模式的研究发展到对成矿系列、成矿系统的全面探讨和整体认识,妥善处理了局部与整体、片面与全面、个体与群体、定性与定量、时间与空间等种种复杂关系,这种研究思路上的变化体现了系统的、辨证的哲学思维方法。  相似文献   

闽东南长乐-南澳断裂带“片麻状”浆混杂岩的厘定及其地质意义   总被引：9，自引：1，他引：8  

邢光福  卢清地  姜杨  聂童春  陈荣  冯艳芳  陈志洪  余明刚  李春海  黄家龙  柯学 《地质通报》2010,29(1):31-43

近年来的区域地质调查在闽东南长乐-南澳断裂带中,多处新发现白垩纪(辉长)闪长质和二长花岗质岩浆经机械的、化学的混合形成各种浆混岩类,与两混合端元岩石共同构成浆混杂岩,成岩后还受到应力作用。它们因特殊的结构构造而长期被归入混合花岗岩或片麻状花岗岩类。描述了泉州市肖厝、福清市高山等地浆混杂岩的野外地质特征,并与莆田市和福清市的典型变质变形花岗岩类进行了对比,指出这3类岩石之间有明显的区别,浆混杂岩可能形成于主变质变形期之前早白垩世早期的伸展环境中。  相似文献   

The response of soil CO<Subscript>2</Subscript> efflux to desertification on alpine meadow in the Qinghai–Tibet Plateau     

Fang Zhang  Tao Wang  Xian Xue  Bangshuai Han  Fei Peng  Quangang You 《Environmental Earth Sciences》2010,60(2):349-358

Assessing the global C budget requires a better understanding of the effect of environmental factors on soil CO₂ efflux from both experiments and theoretical research, especially in different desertified lands in the Qinghai–Tibet Plateau. Based on the enclosed chamber method, soil CO₂ efflux in four different desertified lands and one control [alpine meadow (AM)] were measured in June, August and September, 2008, respectively. Soil CO₂ efflux rates at the top, the middle, the bottom of a slope and the flat in front of the slope were obtained at Maduo County. The results showed that average daily soil CO₂ efflux rates were 3.72, 2.65, 2.68, 0.59 and 0.37 g m⁻² day⁻¹ in the AM, lightly (LDL), moderately (MDL), severely (SDL) and very severely desertified lands (VSDL) during the growing season, respectively. Soil CO₂ efflux decreased with the change of desertification. The response of soil CO₂ efflux to environmental factors was adequately described by the linear model; models accounted for 76, 65, 72, 59 and 71% of the variability on soil CO₂ efflux in the AM, LDL, MDL, SDL and VSDL, respectively. Any environmental factor, however, was insufficient to explain the soil CO₂ efflux; the common influence could perfectly reflect soil CO₂ efflux response to the desertification change.  相似文献   

天山天池近49年气候变化特征   总被引：5，自引：0，他引：5  

马洪亮  马燕  薛福民 《气象科技》2010,38(2):209-213

基于天山天池气象站1959～2007年的逐日地面气候资料,应用线性倾向估计、功率谱分析、滑动t检验及距平标准差对比分析等方法对天山天池气候变化特征进行了分析。分析表明:天山天池气候变化具有明显的多尺度振荡特征,并且具有明显的年际变化,年平均气温在1996年附近发生突变,降水未出现气候突变现象。气温和降水的变化和天山山区"暖湿型"变化趋势一致,最低气温的升高对天山天池增温贡献最大,最显著增湿趋势出现在春季和冬季,夏季降水量持平而雨日却减少,夏季极端强降水天气增加。  相似文献