蒙古国塔南凹陷南屯组水下扇的沉积演化特征     

刘招君  张迪  贾建亮  蒙启安  陈永成  方石  苗长盛  韩娇艳 《吉林大学学报(地球科学版)》2012,(Z1):1-7

利用基于Wheeler变换的数据驱动倾角导向体生成的非线性年代地层切片,研究蒙古国塔南凹陷下白垩统南屯组水下扇的沉积演化特征。基于沉积学的理论指导,通过单井相、连井相标定,结合地震反演、地震属性等技术,进行等时地层单元的沉积相分析;基于相控应用年代地层切片技术研究沉积演化特征。结果表明:塔南凹陷南屯组SQ21时期发育近岸水下扇及远岸水下扇,水下扇的沉积演化规模随着水体的加深先扩张后萎缩,到最大湖泛时期基本消失;切片中水道显示远岸水下扇是近岸水下扇二次搬运至同生断裂再次滑塌而成。  相似文献   

中国西北部含油气盆地的构造带类型及其复式油气藏(田)初探     

杨津  刘迪  吴红华  杨克绳 《海相油气地质》2012,17(1):1-9

中国西北部含油气盆地具有四大类型有利油气成藏构造带,包括前陆带、中央隆起带、凹陷背斜带和斜坡构造带。前陆带还可分为前陆隆起带、前陆逆冲断裂带及前陆逆冲前锋带三个亚类。这些构造带控制了油气藏的形成与聚集,构成了在垂向上相互叠置、平面上复合连片,形成不同的复式油气聚集区。前陆带主要分布在塔里木盆地西南缘和北缘、准噶尔盆地西北缘和南缘、吐哈盆地北缘、酒泉盆地南缘以及柴达木盆地北缘;中央隆起带仅在塔里木、准噶尔两个盆地发育;凹陷背斜带的典型实例为塔里木盆地英吉苏凹陷中部的英南构造带,另外还包括塔里木盆地满加尔凹陷哈德逊东河砂岩不整合超覆尖灭带和准噶尔盆地漠区坳陷的莫西断鼻等;斜坡构造带以柴达木盆地红柳泉斜坡构造带为代表,它由地层不整合圈闭和地层超覆圈闭形成复合构造样式。  相似文献   

节能型深部找矿长寿命金刚石钻头野外生产试验效果     

刘树华  孙鑫  王迪  苑春雷  田巍  朱英 《吉林地质》2012,31(2):123-127

为提高钻头寿命研究出新的胎体配方及烧结工艺,设计了新的钻头水路,使钻头胎体高度达到12～15mm,新钻头较普通钻头寿命有明显提高,达到试验研究目的。  相似文献   

Temporal and spatial distribution of trace metals in sediments from the northern Yellow Sea coast,China: implications for regional anthropogenic processes     

Qianli?SunEmail author  Dongyan?Liu  Tao?Liu  Baoping?Di  Feng?Wu 《Environmental Earth Sciences》2012,66(3):697-705

Surface sediment samples from 17 sites in the Yantai coastal area, the northern Yellow Sea, China, combined with a sediment core were employed for geochemical and chronological analyses for the purpose of characterizing the temporal and spatial distribution of trace metals in sediments and their implications for anthropogenic processes. The results indicated that the spatial distribution of trace metals (Cr, Ni, Ti, Pb, As, Zn, Mn and Cu) in surface sediments was significantly contributed by the sewage discharges along the Yantai coast, and the coastal currents played a major role for transporting the pollutants to offshore. The temporal concentrations of trace metals in the sediment core based on the chronology determined by a combination of radionuclide ¹³⁷Cs and ²¹⁰Pb activity demonstrated that trace metal concentrations increased step-wisely over the last ca. 100 years, corresponding to the intensity of anthropogenic processes in the Yantai area. The high levels of Cu and As before the late 1970s indicated the agricultural emission from the application of pesticides. While, all the high-trace metal concentrations since the early 1980s could be seen as diagnostic indictors of increasing industrialization, urbanization and sewage discharge in the Yantai area. Although the potential ecological risk evaluation of trace metals in the coastal area suggests low-potential ecological risk at present, some trace metals, such as As and Pb need particular attention due to their slight contamination.  相似文献   

我国人均水资源量分布的俱乐部趋同研究——基于扩展的马尔科夫链模型          下载免费PDF全文

周迪  周丰年  钟绍军 《干旱区地理》2018,41(4):867-873

研究区域水资源不平衡背后的“俱乐部趋同”现象,对于水资源调节以及水资源均衡配置具有重要的理论和实践意义。基于2004-2015年我国31个省（市、区）的人均水资源数据,利用扩展的马尔科夫链模型检测了不同时长下我国省际水资源量分布的俱乐部趋同现象,并分析了其时间特征。结果表明：即使在5 a的时间积累下,我国人均水资源量仍存在着明显的俱乐部趋同现象,高水平和低水平地区水资源量分布高度固化,且俱乐部趋同程度在2008年开始向恶化的趋势发展,可见当前我国区域水资源调节力度有待进一步加强。最后论文根据各地区人均水资源在考察期各年所属俱乐部类型、类型转移频率等因素对各地区进行了分类,以对区域水资源调节提供支持和参考。  相似文献   

The volcanic history of Mars: High-resolution crater-based studies of the calderas of 20 volcanoes     

Stuart J. Robbins  Gaetano Di Achille  Brian M. Hynek 《Icarus》2011,211(2):1179-151

Determining absolute surface ages for bodies in the Solar System is, at present, only possible for Earth and Moon with radiometric dating for both bodies and biologic proxies such as fossils for Earth. Relative ages through cratering statistics are recognized as one of the most reliable proxies for relative ages, calibrated by lunar geologic mapping and Apollo program sample returns. In this work, we have utilized the Mars Reconnaissance Orbiter’s ConTeXt Camera’s images which provide the highest resolution wide-scale coverage of Mars to systematically crater-age-date the calderas of 20 of Mars’ largest volcanoes in order to constrain the length of time over which these volcanoes - and major volcanic activity on the planet, by extension - were active. This constitutes the largest uniform and comprehensive research on these features to date, eliminating unknown uncertainties by multiple researchers analyzing different volcanoes with varied data and methods. We confirm previous results that Mars has had active volcanism throughout most of its history although it varied spatially and temporally, with the latest large-scale caldera activity ending approximately 150 ma in the Tharsis region. We find a transition from explosive to effusive eruption style occurring in the Hesperian, at approximately 3.5 Ga ago, though different regions of the planet transitioned at different times. Since we were statistically complete in our crater counts to sizes as small as ∼60 m in most cases, we also used our results to study the importance of secondary cratering and its effects on crater size-frequency distributions within the small regions of volcanic calderas. We found that there is no “golden rule” for the diameters secondaries become important in crater counts of martian surfaces, with one volcano showing a classic field of secondaries ∼2 crater diameters from the center of its primary but not affecting the size-frequency distribution, and another clearly showing an influence but from no obvious primary.  相似文献   

Computational radiation hydrodynamics     

C. Michaut  H. C. Nguyen  L. Di Menza 《Astrophysics and Space Science》2011,336(1):175-181

This paper deals about pure hydrodynamic and radiation hydrodynamic codes developed at LUTH, dedicated to astrophysical simulations. The studied phenomena in this area are often encountered at high Mach number and in a radiation regime where no a priori assumption can be made on the radiation transfer. The radiative hydrodynamic code HADES has to can perform simulations as well as any optical depths, from smallest to highest. Validation of numerical schemes or physical assumptions will be made by laboratory astrophysical experiments. Therefore a very wide domain of initial conditions has to be accepted for computing. A succinct presentation of three codes is done, accompanied with some astrophysical applications.  相似文献   

Mission-constrained design drivers and technical solutions for the MAGIA satellite     

Giorgio Perrotta  M. Stipa  D. Silvi  S. Coltellacci  G. Curti  G. Colonna  T. Formica  V. Casali  T. Fossati  F. Di Matteo  M. Zelli  M. Rinaldi  L. Ansalone  A. Di Salvo 《Experimental Astronomy》2011,32(1):63-82

The Mission MAGIA (Missione Altimetrica Geofisica GeochImica lunAre) was proposed in the framework of the ??Bando per Piccole Missioni?? of ASI (Italian Space Agency) in 2007. The mission was selected for a phase A study by ASI on February 7th 2008. The tight budget allocation, combined with quite ambitious scientific objectives, set challenging requirements for the satellite design. The paper gives a fast overview of the payloads complement and of the mission-constrained design drivers, including cost minimization, risk reduction, and AIT flexibility. The spacecraft architecture is then outlined, along with an overview of the key subsystems and trade-offs. Some details are given of a Moon gravitometric experiment based on a mother?Cdaughter satellite configuration with the daughter being a subsatellite released from the MAGIA satellite and intended to circle the Moon at a very low altitude. Budgets are appended at the end of the paper showing the key study results.  相似文献   

基于CLM4.5的高寒草地辐射收支和水热交换的数值模拟研究     

吴笛  胡泽勇  付春伟  王树金  樊威伟 《高原气象》2022,41(1):107-121

利用那曲高寒气候环境观测研究站本部BJ观测点2014年6-8月的近地层观测资料,结合CLM4.5陆面模型,探究空气动力学粗糙长度、叶面积指数、植被覆盖度和热力学粗糙长度参数化方案的改变对陆面能水平衡的模拟结果产生的影响,并且探讨了粗糙度及植被状态指数影响陆面能水平衡模拟性能的机制.结果表明:(1)CLM4.5默认的热力...  相似文献   

Variability of the health effects of crystalline silica: Fe speciation in industrial quartz reagents and suspended dusts—insights from XAS spectroscopy     

Francesco Di Benedetto  Francesco D’Acapito  Fabio Capacci  Gabriele Fornaciai  Massimo Innocenti  Giordano Montegrossi  Werner Oberhauser  Luca A. Pardi  Maurizio Romanelli 《Physics and Chemistry of Minerals》2014,41(3):215-225

We investigated the speciation of Fe in bulk and in suspended respirable quartz dusts coming from ceramic and iron-casting industrial processes via X-ray absorption spectroscopy, with the aim of contributing to a better understanding of the variability of crystalline silica toxicity. Four different bulk industrial quartz powders, nominally pure quartz samples with Fe contents below 200 ppm, and three respirable dusts filters were selected. Fe speciation was determined in all samples through a coupled study of the X-ray absorption near-edge structure and extended X-ray absorption fine structure regions, operating at the Fe–K edge. Fe speciation revealed common features at the beginning of the different production processes, whereas significant differences were observed on both respirable dusts and bulk dusts exiting from the production process. Namely, a common pollution of the raw quartz dusts by elemental Fe was evidenced and attributed to residuals of the industrial production of quartz materials. Moreover, the respirable samples indicated that reactivity occurs after the suspension of the powders in air. The gravitational selection during the particle suspension consistently allowed us to clearly discriminate between suspended and bulk dusts. On the basis of the obtained results, we provide an apparent spectroscopic discrimination between the raw materials used in the considered industrial processes, and those that are effectively inhaled by workers. In particular, an amorphous Fe^III oxide, with an unsaturated coordination sphere, can be related to silica reactivity (and health consequences).  相似文献