成都国际会展中心输气管线府河穿越隧道涌水量预测

成都拟建国际会展中心供气工程府河输气隧道在府河河底以下40m,采用“竖井＋隧道＋竖井”方案。隧址位于府河及其Ⅰ级阶地,隧道涌水问题严重。为保证施工、运营的安全,在分析隧址区水文地质条件的基础上,对隧道涌水做出初步预测评价,为施工提供依据.     

松辽盆地宋芳屯油田扶杨油层储层成岩作用研究

宋芳屯油田扶杨油层储集岩主要为混合砂岩,泥质含量高、钙质胶结物含量较高。对储层的成岩序列进行了研究,储层大部分进入早成岩阶段B期和晚成岩阶段A期;主要的成岩事件有压实作用、胶结作用、溶蚀作用、交代作用等;压实作用是使孔隙降低的主要原因,钙质胶结物存在使孔隙空间进一步降低,骨架颗粒的溶蚀作用增加孔隙空间;扶杨油层储层敏感性主要有水敏、速敏和酸敏。     

Assessment of Air Temperature Trends in the Source Region of Yellow River and Its Sub-Basins,China

Changes in climatic variables at the sub-basins scale (having different features of land cover) are crucial for planning, development and designing of water resources infrastructure in the context of climate change. Accordingly, to explore the features of climate changes in sub-basins of the Source Region of Yellow River (SRYR), absolute changes and trends of temperature variables, maximum temperature (Tmax), minimum temperature (Tmin), mean temperature (Tavg) and diurnal temperature range (DTR), were analyzed annually and seasonally by using daily observed air temperature dataset from 1965 to 2014. Results showed that annual Tmax, Tmin and Tavg for the SRYR were experiencing warming trends respectively at the rate of 0.28, 0.36 and 0.31°C (10 yr)^?1. In comparison with the 1st period (1965-1989), more absolute changes and trends towards increasing were observed during the 2nd period (1990-2014). Apart from Tangnaihai (a low altitude sub-basin), these increasing trends and changes seemed more significant in other basins with highest magnitude during winter. Among sub-basins the increasing trends were more dominant in Huangheyan compared to other sub-basins. The largest increase magnitude of Tmin, 1.24 and 1.18°C (10 yr)^?1, occurred in high altitude sub-basins Jimai and Huangheyan, respectively, while the smallest increase magnitude of 0.23°C (10 yr)^?1 occurred in a low altitude sub-basin Tangnaihai. The high elevation difference in Tangnaihai probably was the main reason for the less increase in the magnitude of Tmin. In the last decade, smaller magnitude of trend for all temperature variables signified the signal of cooling in the region. Overall, changes of temperature variables had significant spatial and seasonal variations. It implies that seasonal variations of runoff might be greater or different for each sub-basin.     

浑善达克沙地飞播区植被动态

采用空间代替时间的方法,连续4年对浑善达克沙地飞播区（1999-2015年）植被进行调查,分析飞播植被演替进程中群落物种组成、多样性以及飞播植物种群盖度的动态变化,以期揭示飞播措施下的植被恢复规律,为飞播区植被稳定性维持提供依据。结果表明：（1）对照与演替初期生活型以一、二年生草本植物为主,随着演替时间的增加,多年生植物种类增加,逐渐取代一、二年生草本植物优势地位;演替9 a时原生植物入侵明显。（2）演替4 a时Pielou均匀度指数最高,演替9 a时Partrick丰富度指数最高,演替10 a时Shannon-Wiener多样性指数最高,在演替进程中,3个指数变化不一致。（3）羊柴种群在演替8 a时达到峰值（68.33%）,种群能维持较长时间;白沙蒿种群在演替3 a时达到峰值（10.17%）,在演替11 a时退出;沙打旺种群在演替4 a时达到峰值（12.67%）,在演替9 a时退出;沙地榆种群盖度呈缓慢增加的线性趋势。飞播措施下浑善达克沙地植被能快速恢复,有利于植被自然演替。在浑善达克沙地生态建设中,应先考虑沙地的恢复力再决定是否飞播。     

基于第一类无奇点根数的LEO历书参数设计

GNSS技术蓬勃发展,在国防建设和国民经济发展中发挥了重要作用。但也因其无法快速解算整周模糊度、复杂环境下适应性差、完好性差等缺点,限制了其作用的最大发挥。基于LEO通信卫星星座的系统增强可以很好地克服这些缺点。要实现该增强系统,基础之一就是如何生成LEO卫星的历书星历。为解决这个问题,从第一类无奇点出发对GPS标准历书进行改造,提出了一套专用于LEO卫星的10参数历书集,并推导了历书计算公式。对600~1 500 km轨道高度的2~7 d的LEO卫星轨道进行了拟合实验。结果表明,高度600 km时长2 d,高度700 km时长4 d,高度800 km时长7 d历书拟合的用户距离误差(URE)的均方根误差(RMS)分别优于936.021,944.087和956.183 m。     

鄂尔多斯盆地东北部差异隆升过程裂变径迹分析

基于磷灰石裂变径迹(AFT)的分析方法,探讨鄂尔多斯盆地东北缘差异隆升过程及其隆升强度,为鄂尔多斯盆地东北缘(晋西挠摺带府谷—吴堡区段)构造演化历史及其与多种能源矿产耦合关系提供新的认识。不同构造单元及其不同层系样品的AFT分析表明:研究区北段府谷—兴县地区构造抬升相对较早,且经历了白垩纪晚期(86~56Ma)和古近纪(44~37 Ma)两次隆升过程,平均隆升速率分别为24.5 m/Ma和41.8 m/Ma;研究区中段紫金山地区抬升相对较晚,主控构造事件发生在晚白垩世末期—古近纪早期(68~56 Ma)和古近纪中晚期(35 Ma),平均隆升速率分别为48.8 m/Ma和49.2 m/Ma;研究区南段临县—吴堡地区抬升最晚(35~21 Ma),平均隆升速率为73.9 m/Ma。因此,鄂尔多斯盆地东北缘晚白垩世以来的差异隆升过程具有北段抬升早、中段抬升相对较晚和南段抬升更晚的特点,南北区段统一的强烈构造抬升活动主要发生在古近纪以来的晚近时期,且构造隆升强度由南向北逐渐减弱。结合已有的成矿(藏)年代学资料分析表明,鄂尔多斯盆地东北缘关键构造事件及其隆升强度与多种矿产耦合成矿(藏)事件关系密切,构造事件与成藏(矿)事件呈现出显著的协同耦合特点。     

At‐a‐station hydraulic geometry relations, 2: calibration and testing

Using a large number of data sets obtained from various sources, the geometric relations derived in Part 1 are calibrated and verified using the split sampling approach. The calibration of parameters shows that the change in stream power is not shared equally among hydraulic variables and that the unevenness depends on the boundary conditions to be satisfied by the channel under consideration. The agreement between the observed values of the hydraulic variables and those predicted by the derived relations is close for the verification data set and lends credence to the hypotheses employed in this study. Copyright © 2007 John Wiley & Sons, Ltd.     

Effects of mid‐twenty‐first century climate and land cover change on the hydrology of the Puget Sound basin,Washington

The distributed hydrology–soil–vegetation model (DHSVM) was used to study the potential impacts of projected future land cover and climate change on the hydrology of the Puget Sound basin, Washington, in the mid‐twenty‐first century. A 60‐year climate model output, archived for the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4), was statistically downscaled and used as input to DHSVM. From the DHSVM output, we extracted multi‐decadal averages of seasonal streamflow, annual maximum flow, snow water equivalent (SWE), and evapotranspiration centred around 2030 and 2050. Future land cover was represented by a 2027 projection, which was extended to 2050, and DHSVM was run (with current climate) for these future land cover projections. In general, the climate change signal alone on sub‐basin streamflow was evidenced primarily through changes in the timing of winter and spring runoff, and slight increases in the annual runoff. Runoff changes in the uplands were attributable both to climate (increased winter precipitation, less snow) and land cover change (mostly reduced vegetation maturity). The most climatically sensitive parts of the uplands were in areas where the current winter precipitation is in the rain–snow transition zone. Changes in land cover were generally more important than climate change in the lowlands, where a substantial change to more urbanized land use and increased runoff was predicted. Both the annual total and seasonal distribution of freshwater flux to Puget Sound are more sensitive to climate change impacts than to land cover change, primarily because most of the runoff originates in the uplands. Both climate and land cover change slightly increase the annual freshwater flux to Puget Sound. Changes in the seasonal distribution of freshwater flux are mostly related to climate change, and consist of double‐digit increases in winter flows and decreases in summer and fall flows. Copyright © 2010 John Wiley & Sons, Ltd.     

对中国金矿床成因分类的评述

对中国金矿床成因分类研究的现状和一些有代表性的分类方案进行了简要评述.其中较有影响的成因分类可归纳为以下几类:(1)以成矿作用为基础的成因分类;(2)以成矿物质为基础的分类方案;(3)以赋矿岩石组合为基础的分类方案;(4)以金矿床产出的地质构造单元为基础的分类方案.     

辽宁新甸金矿床成因

元古宇辽河群盖县组是一套黏土、半黏土质陆源碎屑沉积夹中-酸性火山岩或火山碎屑岩沉积建造,在地质历史发展过程中发生了变形变质作用,导致岩石中的硅质成分分异而形成硅化石英脉,同时,岩石中的成矿物质也发生了初步的迁移和富集.燕山期的花岗岩浆活动交代重熔了变质岩系,变质岩系中大量的成矿物质被活化、迁移至岩浆期后热液中,在成矿热液演化为偏酸性-还原性条件下,金等成矿元素发生了沉淀作用.稳定同位素、稀土元素特征表明金矿床的成矿物质来源于盖县组变质岩系,成矿热液为岩浆期后热液.伴随岩浆活动产生的一系列剪切构造既为成矿热液运移提供了通道,也为矿质沉淀提供了有利空间.新甸金矿床属于岩浆期后热液型矿床.