Triple Medium Physical Model of Post Fracturing High-Rank Coal Reservoir in Southern Qinshui Basin

In this paper, influences on the reservoir permeability, the reservoir architecture and the fluid flow pattern caused by hydraulic fracturing are analyzed. Based on the structure and production fluid f...     

青藏高原高寒湿地生态系统演变、修复与保护

 探讨了青藏高原高寒湿地的动态变化及演变趋势，分析了湿地面积变化、生态系统结构与功能退化现状与原因。分析表明，国家近20年来在青藏高原实施的生态保护、修复及生态工程项目取得了一定的成效，但高寒湿地生态系统的退化形势依然严峻。生态保护和修复是一项系统、长期的工作，今后要加强生态修复技术研发项目与工程类项目的衔接，建立长效管理机制，提高退化湿地的自然恢复能力。同时，要构建适于青藏高原高寒湿地保护效应的评价模型和指标体系，完善重大工程项目的系统监测与评价。在黄河、长江上游源区布局高寒湿地生态系统的长期监测，将与三江源区同样重要的黄河首曲湿地、若尔盖湿地纳入国家公园管理体系，统筹规划，建立健全科技服务平台和信息共享机制。     

南方多雨地区宜采用的尾矿干堆工艺及环境影响分析

传统的尾矿处理方法是采取尾矿湿排技术,即建立尾矿库湿式堆存;为解决尾矿湿式堆存受地形、土地占用、安全和环保等方面的限制,目前国内发展了尾矿干式堆存新技术,尾矿干式堆存具有很好的发展前景。我国南方属多雨地区,使尾矿干堆工艺的运用受到了一定限制。结合目前常用的滤饼、膏体和袋式3种尾矿干堆工艺,从处理工艺流程、适宜条件和对环境影响等方面作了比较,提出了适宜南方多雨地区的尾矿干堆工艺。     

Climatic significance of n-alkanes and their compound-specific dD values from lake surface sediments on the Southwestern Tibetan Plateau

The content and hydrogen isotope ratios of n-alkanes extracted from recent lake surface sediments sampled from nine lakes in three different climate zones on the Southwestern Tibetan Plateau were analyzed.Values were compared with n-alkanes in plants from lake drainages,and dD values of meteoric water,lake water,and mean annual precipitation.The results showed that n-C23was predominantly derived from aquatic plants,and n-C27–n-C33from terrestrial higher plants.The average carbon chain length of n-C27–n-C33(ACL27–33)was positively correlated with the mean annual precipitation.dD values of the long-chain n-alkanes n-C29and n-C31of terrestrial origin(varying between-214%and-169%,and-226%and-185%,respectively)were inversely correlated with mean annual precipitation;but in accordance with the average annual variations in dD(OIPC),dD values of n-C31were strongly related to the dD values of growing season meteoric water(R2=0.74).The large difference between dD values of n-C23of aquatic origin and n-C31(an average of about 27%)demonstrates the enrichment of the lake water dD compared to precipitation,caused by strong evaporation in the semiarid–arid areas of the southwestern Tibetan Plateau.Average value of en C25 31=p(-95%)is evidently higher than the value observed in European wet regions(-128%);besides,en C31(about-116%)is constant along the study transect(SD=9),which indicates that n-C31is a useful proxy for the environment.     

Opening of the Longmu Co–Shuanghu–Lancangjiang ocean:constraints from plagiogranites

This paper reports new zircon U-Pb ages,and Hf isotope and whole-rock major and trace element data for Cambrian plagiogranites from the Tuobeiling ophiolite in central Qiangtang,Tibetan Plateau.Zircon SIMS and LAICP-MS U-Pb dating of the plagiogranites yield weighted mean ages of 504.8±4.2 and 491.6±1.5 Ma,respectively.The zircons from plagiogranites exhibit positive eHf(t)values(ranging from 11.46 to 15.16),indicating that the plagiogranites are derived from depleted mantle.These plagiogranites are characterized by high SiO2and Na2O,low K2O,low REE contents,and flat REE distribution patterns.These rocks have geochemical compositions typical of oceanic plagiogranite and,considered along with their petrography and field relationships,are interpreted to have derived from anatexis of hydrated amphibolites by ductile shearing during transports of the oceanic crust.The formation age of such type of plagiogranite is slightly younger than that of the associated section of oceanic crust.Thus the new results from these plagiogranites suggest that the Longmu Co–Shuanghu–Lancangjiang ocean had probably opened before the Middle Cambrian.     

1970～2012年青海湖流域冷暖季气温变化特征及突变分析

本文以线性倾向估计、累积距平、小波分析、Mann-Kendall检验及滑动t检验等方法对青海湖流域1970~2012冷、暖季及年均气温变化趋势、周期性和突变性进行分析.结果表明:(1)青海湖流域冷、暖季气温及年平均气温均呈显著增长趋势,其中,冷季增长幅度最大(0.45℃/10a),暖季增长最平缓(0.22℃/10a);从各站点的年、季气温变化来看,恰不恰地区增温幅度最大,刚察增幅最小.(2)冷、暖季气温及年均温的累积距平值绝大多数为负值,变化趋势相对一致,以1997年为转折点,1997年之前气候偏冷,之后趋于变暖.其中,年均气温变化幅度最小,冷季变化幅度最大.(3)冷、暖季和全年均存在较为复杂的周期性变化,其中,年平均气温在整个时间序列上存在4a和15a的周期,以15a最为显著;冷、暖季平均气温在短时间尺度上周期性不显著,主要为17a和27a的长时间尺度周期,以17a的变化周期最显著.(4)青海湖流域冷、暖季气温和年平均气温经检验均发生了突变,其中,年平均气温发生于90年代前期,冷、暖季均发生于90年代中期,且均于90年代末进入显著增温阶段.     

生态建设工程对坝上农用地土壤风蚀治理的后效——以河北省张家口市康保牧场为例

通过在农牧交错带河北省张家口市坝上高原康保牧场野外调查研究,采用标桩法测定土壤风蚀厚度,计算土壤年风蚀量,采用目测法测定样地植被盖度.将该地生态建设初期与生态建设10年后的土壤风蚀量作对比.结果表明:生态建设十年后土壤风蚀量比生态建设初期土壤风蚀量明显减少,植被盖度明显增加.并提出巩固生态工程建设成果的若干建议.     

青海哈西亚图多金属矿床地质特征及成因探讨

为了加快青海省优势环境与战略矿产勘查进程,文中对哈西亚图多金属矿床成矿地质背景、矿床地质特征、控矿因素及成因进行了综合分析,研究结果表明:哈西亚图多金属矿床已发现矿体的成因类型为矽卡岩型,矿体从垂向上看,可分为4层均产于具垂直分带的矽卡岩带中,受矽卡岩类型影响矿石类型在垂向上也具有明显分带性,在华力西期花岗闪长岩与古元古界金水口岩群的碳酸盐岩的接触带附近为主要成矿部位,通过早期区域变质作用、矽卡岩化作用及晚期的热液成矿作用3个阶段,形成了以磁铁矿体为主,铜、铅、锌、金并存的多金属矿床。     

青海大学思想政治理论课课程群建设与改革的探索

课程群建设顺应高校教学改革的要求,是整体推进思想政治理论课教学改革的必由之路,基于此,青海大学从课程群建设的理念出发进行思想政治理论课改革,在思想政治理论课课程之间的衔接、教学资源共享、教学团队的培育、课程实践教学以及延伸课的开发等方面进行了有益的探索。     

松南中央坳陷泉四段上生下储式致密砂岩油成藏主控因素

基于"优质源岩控藏"理论和"储层甜点找油"思想,应用测、录井、试油、薄片等资料,系统总结松南中央坳陷区泉四段致密油的分布规律,剖析不同类型致密砂岩油成藏的主控因素。研究表明:致密砂岩油藏集中分布在长岭凹陷内及其周边斜坡区,具有"满坳含油、宏观连片"的特征和"东富西贫、南富北贫"的差异性;青一段下段烃源岩残余有机碳含量(TOC)大于2.0%的优质源岩展布范围控制致密油藏分布格局;异常高压与源储断层的空间配置关系控制下部砂组含油性,剖面上油气下排深度最大为140 m;平面上超压大于10 MPa、与断层距离小于2 500 m的区域是Ⅱ~Ⅳ砂组的致密油藏富集区;优质储层物性"甜点"控制致密油富集程度及产量;坳陷型湖盆上生下储式致密砂岩油藏的形成主要存在凹陷区"源内直排倒灌"和斜坡区"源边反转断层遮挡"两种成藏模式。