山西流体观测井水位与气压相关性分析

分析了山西省流体观测井水位动态特征,利用高阶差分、回归分析方法计算了2008年山西省各观测井水位与气压相关系数,得到了气压系数的背景值,进而对气压干扰因素进行定量化的排除,并对各井的气压系数进行对比分析。结果表明,不同的观测井孔水位受气压影响程度不同,对于某一个观测井孔而言,气压系数及相关系数的变化是有一定规律的。     

Early Paleozoic ridge subduction in the Chinese Altai: Insight from the abrupt change in zircon Hf isotopic compositions

Zircons were separated from granitoids, gneisses, and sedimentary rocks of the Chinese Altai. Those with igneous characteristics yielded U-Pb ages of 280-2800 Ma, recording a long history of magmatic activity in the region. Zircon Hf isotopic compositions show an abrupt change at ~420 Ma, indicating that prior to that time the magmas came from both ancient and juvenile sources, whereas younger magmas were derived mainly from juvenile material. This may imply that the lithosphere was signifi- cantly modified...     

Oil and gas potential assessment for coal measure source rocks on absolute concentration of n-alkanes and aromatic hydrocarbons

Absolute concentration of normal alkanes (n-alkanes) and aromatic hydrocarbons in bitumen extracted from source rocks in the period of thermodegradation from Turpan-Hami Basin suggests that aromatic hydrocarbons are dominant in coal and carbargilite while n-alkanes are dominant in mudstones. Bulkrock analysis and gas chromatograph/mass spectrum (GC-MS) of source rocks shows aromatic hydrocarbons are dominant in total ion chromatograms (TIC) of samples with poor perhydrous macerals while n-alkanes are dominant in TICs of samples with abundant perhydrous macerals. The identification of oil-prone and gas prone property based on GC-MS of bitumen “A” together with bulkrock analysis indicates that source rocks from Shengbei area are more oil-prone while source rocks from Qiudong and Xiaocaohu areas are more gas-prone, coinciding with the distribution of oil and gas reservoirs in Taibei Sag. Ratios used to identify oil-prone and gas-prone property for source rocks from Turpan Basin are proposed: n-alkanes >110 μg·mg^?1, aromatics <15 μg·mg^?1, and n-alkanes/aromatics >8 for oil-prone source rock bitumen while n-alkanes <82 μg·mg^?1, aromatics >40 μg·mg^?1, and n-alkanes/aromatics <1.5 for gas-prone source rock bitumen.     

Distribution of the indigenous microorganisms and mechanisms of their orientational activation in Daqing Oilfield

The distribution of indigenous microorganisms was surveyed in Block 1 of Daqing Oilfield. Based on this survey, the indigenous microorganisms in the formation water were activated with different activator systems at the simulated stratum ecological environment. The changes of the number of bacteria of various physiological groups were determined during the process of activation. Also changes of pH value and composition of gas productions were analyzed at the end of culturing. The results showed that the selected block formation water contained a great number of saprophytic bacteria, hydrocarbon-oxidizing bacteria, fermentative bacteria, methane-producing bacteria and sulfate-reducing bacteria. Under the conditions that the growth of sulfate-reducing bacteria was controlled the block had the potential to enhance oil recovery by activating beneficial bacteria. The growth of sulfate-reducing bacteria can be inhibited through the activation of nitrate-reducing bacteria. The number of nitrate-reducing bacteria reached 10⁶–10⁷ cells/mL, but sulfate-reducing bacteria reached only 0–45 cells/mL in A system. Methane-producing bacteria can be activated by C, D activators. The relative content of biological methane in the light hydrocarbon gas reached 80% in C, D systems. B activator was conducive to the propagation of acid-producing bacteria, so that the pH value of the culture medium decreased from 7.5 to around 5.0. Hydrocarbon-oxidizing bacteria can be activated by various activator systems. There was low molecular light hydrocarbon in gas production according to the analysis of gas chromatograph. According to the content of methane and the number of methane-producing bacteria, methane only can be generated through activating methane-producing bacteria. By choosing different activator systems, various populations of indigenous microorganisms can be activated accordingly.     

昆仑8.1级地震同震形变特征及其对响应地震活动的制约机制

本文定义”响应地震”的概念统一表述昆仑山口西8.1级地震所引发的主破裂两侧临近构造及部分块体边界上的显著地震活动.其主体活动区域集中在昆仑地震主破裂的西南侧和东北侧及祁连山断裂.同时,地壳运动在主破裂北侧的甘青块体中西部出现与背景运动场反向的特征性变化,祁连山断裂出现应变弱化.弹性位移-应力阶跃模型模拟结果显示,昆仑地震造成其东北侧甘青块体中西部地壳运动的反向运动(相对背景场).并形成东北部和西南部两个体应变张性区域,绝大部分响应地震都发生在应变张性区中和块体张性边界上.这种强烈挤压剪切背景中出现的相对松弛状态与昆仑地震后青藏块体地震弱活动背景中出现的显著活跃的响应地震活动的正相关性可能反映了断层约束状态的相对减弱对滑动的触发作用.说明在考虑地震发生条件时,不能只着眼于应力场是否增强,断层摩擦强度,或更广义地说,构造约束条件的变化也是一个不容忽视的重要因素.     

西大别浒湾高压变质带变沉积岩锆石U-Pb年龄及地质意义

西大别山浒湾高压变质带是研究秦岭-大别山-苏鲁造山带演化的关键区域, 但是该地区榴辉岩相变质时间还存在较大争议.本文通过对浒湾变质带熊店附近的一个变沉积岩样品进行LA-ICPMS锆石U-Pb定年和微量元素分析, 来确定该地区榴辉岩相变质作用和碎屑锆石的年龄, 并确定该变质带的演化历史.该样品的变质锆石具有弱分带或无分带、低Th/U比值、重稀土含量低且相对平坦以及无明显的Eu负异常等特征.反映这些变质锆石形成时有石榴石, 而缺乏长石, 其形成对应于榴辉岩相变质作用条件.该样品中变质锆石的206Pb/238U加权平均值为310±3Ma, 这一年龄代表了该地区榴辉岩相峰期变质作用的时间, 因此浒湾地区榴辉岩相变质作用时间为石炭纪.碎屑岩浆锆石得到了3组近谐和的U-Pb年龄, 其206Pb/238U年龄变化范围分别为: 400±5Ma~419±5Ma、426±5Ma~449±5Ma以及496±5Ma~524±7Ma, 还有1个颗粒给出了580±7Ma的较老年龄.这些结果表明变沉积岩中的碎屑锆石可能大部分来自于华北板块南缘, 少量来自于扬子板块.      

中国4个国家级野外站大气CH4本底浓度变化特征

CH4是仅次于CO2的重要温室气体。2006年9月至2008年8月期间,按全球大气本底观测要求,在青海瓦里关、北京上甸子、浙江临安和黑龙江龙凤山4个国家级野外站开展每周一次空气样品flask瓶采样分析,获得了该地区为期2 a的大气CH4本底浓度资料。结果表明,2 a间瓦里关、上甸子、临安和龙凤山4站CH4浓度年均增幅分别为9.1×10-9、3.8×10-9、21.8×10-9和8.2×10-9;瓦里关站大气CH4浓度增长趋势与全球平均状况较为接近,能较好地反映北半球中高纬度内陆地区大气本底特征;但上甸子站年均本底值相对较低且季振幅偏小,而龙凤山和临安站季节变化规律相似,表现为CH4浓度冬季高而夏季偏低且季振幅较大。     

农村居民国内旅游流空间集中性

旅游流的空间集中性是旅游流研究的热点问题,旅游流空间集中性需要新的审视。本文引入Jansen-Verbeke区域内部流和区域间流界定方法,以2003~2005年中国农村居民国内旅游为案例进行实证分析。结果表明:约70%的旅游流集中于本省内部,旅游流本省内部集中性支撑了"省内旅游"发展战略的认知和实施。"多核非对称旅游系统"已初步形成,其"核心—边缘"特征使得核心区(东部沿海地区)面临巨大的旅游承载压力;在旅游发展加剧区域经济差异的背景下,"边缘旅游"(中、西部地区)如何发展将成为重要课题。     

无锡市现代农业评价体系构建

发展现代农业是促进我国"三农"问题解决的最有效途径之一,也是今后我国农业发展的根本方向。因而亟需建立一套科学的现代农业评价体系,以便对现代农业发展的水平进行评定并指导现代农业建设实践。该评价体系由农业生产、农村发展、农民生活3个方面构成,并以层次分析法赋予各指标权重。同时,以无锡市现代农业发展为实例对指标进行赋值。研究结果表明,无锡市现代农业正处于程度较高的发展期,但仍存在很大的发展空间。针对其发展过程中出现的问题,今后应采取提升农业规模化、机械化水平,加强信息化建设以及促进农民增收等应对措施。     

边坡离心模型试验中的降雨模拟研究

为了在离心机试验中模拟降雨引起的滑坡,设计和使用了一套降雨模拟系统。这套系统的构成主要是针对离心试验的特殊要求进行设计的。所采用的特殊技术可以均匀分配雨水,将雨滴的尺寸效益和科氏加速度引起的雨滴偏移最小化,实现了不同强度和历时的降雨模拟。通过一个降雨条件下砂土边坡的离心模型试验,成功应用了该套降雨模拟系统,研究了边坡中的降雨入渗过程。