横向各向同性介质中地震波速度分析及其意义

在地震学有关领域中，地下介质的薄互层特性与裂隙的定向人布在长波长假设下会产生等效的地震各向异性特性，地震波速度随传播方向和深度发生的变化引起了广大地球物理工作者的广泛兴趣，因为速度拾取的正确与否，会直接影响到油气勘探中动校、偏移、ＡＶＯ和时深转换的结果。本文着重讨论了传统速度分析的局限性，分析了薄互层引起的横向各向同性介质中速度分析的现状和结果，实例讨论了各向异性效应对偏移处理的影响，表明各向异性     

荒沟山金矿区的石英矿物特征及在找矿中的应用

通过对矿区的石英矿物特征、成分及石英差热分析的相变温度、红外光谱的波谱特征和光密度数扬统计、分析等，可有效地将矿区含矿石英与非矿石英区分开，并初步得到验证。     

青林省含铁地下水的分布与处理措施

本文根据含铁地下水的形成条件将吉林省含铁地下水划分为四个区,并论述了各区的分布特征。综合国内目前各种地下水除铁技术,着重对各除铁系统的方法、基本原理和适用条件以及经济效益等进行了论述。从环境水文地质学的角度,提出了在含铁地下水区寻找低铁地下水的方法,并通过实例验证是可行的。     

高精度磁测在青海省阿尔茨托山地区划分地质构造中的应用

推断地质构造是磁测资料解释的组成部分,是对基础地质资料进行综合分析的重要参考,内容包括推断构造(断裂构造、火山构造)、地层(磁性火山岩地层、磁性变质岩地层)和侵入岩等。该文以青海省阿尔茨托山地区1∶5万地面高精度磁测成果为例进行分析,对区内的地质构造及岩浆岩分布等形成了一定认识,推断断裂构造17条并划分了区内火山岩地层、侵入岩体的分布范围,进一步完善了区域地质构造格架。     

自动气象站降水实时快速质控算法设计

对降水资料异常进行分类,并在此基础上设计一种有效的实时快速质控算法。具体方法为:将一定范围内的自动站组成一个局域空间,应用空间一致性方法快速筛选出疑误站,然后利用小时降水的空间分布、分钟降水的时程方程以及与气温、湿度的关联特性,开展针对不同异常类型降水资料的二次质量控制。实际测试表明,该综合质量控制算法在质控实时性与准确性间取得了较好的平衡,尤其是对夏季降水有良好的质控效果。     

2014年2月北京PM2.5污染过程及天气形势分析

2014年2月19—27日,北京出现了重度污染及以上水平的霾天气,严重危害着人们的身体健康。以北京该段持续污染过程为研究对象,基于同期气象数据与PM2.5 观测数据,利用SPSS统计软件分析了PM2.5浓度与气象因子间的相关性,探究区域周边城市PM2.5 污染变化特征及其与地面天气形势之间的关系。研究结果表明,在一定的气象条件下,PM2.5 浓度与风速、相对湿度分别呈显著的负相关、正相关,与气压呈负相关,与气温无显著相关关系。同时,比较该时段北京市与周边区域7个城市的PM2.5 浓度变化趋势及后向轨迹分析,发现北京市与周边城市在相似的气象背景条件下,污染过程具有区域性特征。华北地区处于地面高压均压场控制时,地面风速小,逆温层明显,大气层结稳定,区域扩散条件差,弱偏南气流主导时间长,受局地源积累和区域输送的影响,污染物浓度累积上升,可形成持续霾天气。     

Characterization of preferential flow paths between boreholes in fractured rock using a nanoscale zero-valent iron tracer test

Recent advances in borehole geophysical techniques have improved characterization of cross-hole fracture flow. The direct detection of preferential flow paths in fractured rock, however, remains to be resolved. In this study, a novel approach using nanoscale zero-valent iron (nZVI or ‘nano-iron’) as a tracer was developed for detecting fracture flow paths directly. Generally, only a few rock fractures are permeable while most are much less permeable. A heat-pulse flowmeter can be used to detect changes in flow velocity for delineating permeable fracture zones in the borehole and providing the design basis for the tracer test. When nano-iron particles are released in an injection well, they can migrate through the connecting permeable fracture and be attracted to a magnet array when arriving in an observation well. Such an attraction of incoming iron nanoparticles by the magnet can provide quantitative information for locating the position of the tracer inlet. A series of field experiments were conducted in two wells in fractured rock at a hydrogeological research station in Taiwan, to test the cross-hole migration of the nano-iron tracer through permeable connected fractures. The fluid conductivity recorded in the observation well confirmed the arrival of the injected nano-iron slurry. All of the iron nanoparticles attracted to the magnet array in the observation well were found at the depth of a permeable fracture zone delineated by the flowmeter. This study has demonstrated that integrating the nano-iron tracer test with flowmeter measurement has the potential to characterize preferential flow paths in fractured rock.     

连续两次台风过境对东海北部水环境及初级生产力的影响

台风是影响东海最严重的自然灾害之一。本文在现场观测基础上,结合遥感与模型数据,研究了连续两个台风过境对东海北部水环境及初级生产力的影响。研究结果表明:连续两个台风过境情况下,虽然前面台风有助于后续台风对海洋上层进行垂直混合作用,但它对后续台风过后海洋表层温度(SST)的降低以及初级生产力的增加却起到了削弱作用;除了加强垂向混合过程,台风也可以改变海洋上层的平流输运过程,受此影响,部分海区上层温度、盐度以及叶绿素在台风后重新分布;台风对海区次表层叶绿素浓度的改变程度明显高于表层,某些站位次表层叶绿素最大值(SCM)在台风刚过后被破坏,一段时间后SCM又重新出现,而且层内叶绿素浓度远高于台风前水平。     

Undifferenced Cycle Slip Estimation of Triple-Frequency BeiDou Signals with Ionosphere Prediction

With the rapid development of BeiDou satellite navigation system (BDS), high-quality service has been provided in the Asia-Pacific region currently, which will be extended to the whole world very soon. BDS is the first Global Navigation Satellite System that all satellites broadcast the triple-frequency signals. The triple-frequency signals in theory can improve the cycle slip detection that is one of the preconditions in precise positioning by making use of carrier phase. This paper discusses the development of a cycle slip detection method for undifferenced BDS triple-frequency observations in kinematic scenario. In this method, two geometry-free extra-wide-lane combinations and one geometry-free narrow-lane (NL) combinations are employed. The key is to mitigate the between-epoch ionospheric biases in the geometry-free NL combinations. We propose to predict the ionospheric biases of current epoch by using those from its consecutive foregoing epochs. The method is tested with extensive experiments in varying observation scenarios. The results show that in case of sampling interval as small as 5 s, the between-epoch ionospheric biases can be ignored and the correct cycle slips can be determined. Meanwhile in case of lower sampling frequency, one needs to compensate the ionospheric biases of current epoch by using the predicted ionospheric biases. The presented method can correctly detect all cycle slips even if they are as small as 1 cycle.     

顾及等级的城市公园绿地空间布局合理性分析

针对简单两步移动搜索法忽略资源辐射范围差异、对所有资源采用相同阈值范围的缺点,该文依据公园建设的不同标准对研究区域内的公园进行分类,为不同等级的公园设置不同的搜索半径,使得模型与现实情况更为相符,结果更为可靠。以深圳市龙岗区为例,综合运用距离分析、面积分析和改进的两步移动搜索法对研究区域的公园布局评价,评价结果较好地反映了龙岗区公园的布局情况。