多道瞬态瑞雷波法在探测煤矿采空区中的应用

采空区探测是工程建筑和煤矿生产中亟待解决的问题。常规物探方法在对落后的“房—柱”式开采技术造成的面积较小、埋深较浅的采空区进行探测时存在漏报或误报的情况。根据采空区的地球物理特征,探讨多道瞬态瑞雷波技术的探测机理,并通过勘探实例阐述了该方法在浅层煤矿采空区探测中的实用性和有效性。     

西藏地热气体的地球化学特征及其地质意义

西藏水热活动是青苦恼高原碰撞造山过程的产物，其成因类型、物质来源和时空分布与青藏高原的隆升过程密切相关，地热流体（气、液相）中携带有中上地壳乃至地幔物质的深部信息。西藏地热流体可以区分出CO2型和N2型两类气体，其中绝大多数的地热气体样品属于CO2型气体，而典型的N2型气体则较少。前者具有岩浆热源和深循环两种成因类型，后者都是深循环成因。西藏气体样品中的He含量变化范围非常宽，最高的可达到1．5％。在门士热泉，首次检测到地幔He组分，这说明西藏地壳深处有地幔物质侵位。根据He同位素组成推断，羊八井、谷露等处的地壳熔融体中约有3％的地幔组分。西藏地热气体中的N2和Ar组分主要是大气成因，CO2组分大多以海相碳酸盐岩成因为主，混有少量有机沉积物成因CO2。当Log(H2/Ar)处于－0．8－0．3的区间时，H2／Ar地热温度计可以良好地指示热储层的温度范围。实际调查表明：西藏水热活动区大多分布在斑公错－怒江链合带以南地区，高温水热活动区主要出现在雅鲁藏布缝合带和那曲－羊八井－亚东活动构造带沿线。     

The generation of phytoplankton patchiness by mesoscale current patterns

 Elken et al. (1994) suggested that phytoplankton patchiness can be generated by mesoscale eddies in light-limited, nutrient-replete environments. This hypothesis is explored using two ecological models of different physical complexity. The model results support the idea that the coupling of mesoscale eddy circulation and phytoplankton growth leads to differential growth rates and thus generates variability in phytoplankton distributions. The specific circulation of a cyclonic eddy isolates a phytoplankton population in its core. Due to the reduced vertical mixing, a higher growth rate is supported in the core, and phytoplankton concentrations increase compared to the surrounding environment. A one-dimensional model is used to explore the hypothesis in general and to perform sensitivity studies. A more realistic simulation uses a coupled three- dimensional model for the western Baltic Sea. Starting from vertically and horizontally homogeneous distributions for nutrients and plankton, the models generate patchiness due to the proposed mechanism. The described mechanism may apply for other mesoscale variable environments during light-limited growth periods as well, e.g., the frontal region of the Southern Ocean. Received: 31 March 2001 / Accepted: 31 August 2001     

冬半年冷空气过程中期预报业务系统

介绍了一种以数值预报产品为基础，结合预报经验，运用天气学、统计学、能量学诊断、人工智能和延伸预报等多种技术手段，通过综合决策，制作冷空气过程的中期预报方法。     

珠江三角洲工业地域分工研究

本文从专业化部门的数量和发展水平以及专业化部门地区分布和组合两方面揭示珠江三角洲工业地域分工的基本特点。指出新形势下虽然不少县市存在专业化部门多而不精，工业结构趋同的问题，但珠江三角洲地域分工格局已开始形成。文章还讨论了形成工业地域分工特点的原因并提出了完善地域分工的措施。     

A novel ozone sensor for direct eddy flux measurements

A small, lightweight (1.5 kg) and fast-response ozone sensor for direct eddy flux measurements has been built. The basis for detection is the chemiluminescence of an organic dye adsorbed on dry silica gel in the reaction with ozone. The chemiluminescence is monitored with a cheap and small blue-sensitive photomultiplier. At a flow rate of 100 l min^-1 the ozone sensor has a 90% response time of significantly better than 0.1 s with a detection limit lower than 50 ppt at S/N=3. There are no interferences from other atmospheric trace gases like NO_x, H₂O₂ and PAN. Water vapour and SO₂ enhance the chemiluminescence efficiency of the ozone sensor. Since their response times are 22 seconds and 30 minutes, respectively, no correlation between rapid ozone fluctuations and those of these two trace gases is noticed by the ozone sensor when operating at a frequency of 10 Hz.The ozone sensor was tested for several weeks in continuous measurements of ozone fluxes and deposition velocities over different croplands using the eddy correlation technique. Good agreement was found between ozone dry deposition velocities derived from profile measurements and by eddy correlation.     

RSM－16H动测仪在面波法岩土体检测中的应用

对在岩土体检测中推广应用的新技术──瑞雷面波法作了简述，介绍了ＲＳＭ－１６Ｈ型动测仪对稳态和瞬态面波资料的处理实例，并提出了对该仪器在面波测量中的软件改进建议。     

Estimation of drag coefficient over the western desert sector of the Indian summer monsoon trough

In the estimation of momentum fluxes over land surfaces by the bulk aerodynamic method, no unique value of the drag coefficient (C _D) is found in the literature. The drag coefficient is generally estimated from special observations at different parts of the world. In this study an attempt is made to estimate drag coefficient over the western desert sector of India using data sets of Monsoon Trough Boundary Layer Experiment (MONTBLEX) during the summer monsoon season of 1990. For this purpose, the fast and slow response data sets obtained simultaneously from a 30 m high micro-meteorological tower at Jodhpur are used. All the observations used in this study are confined to a wind speed regime of 2.5–9.0 ms⁻¹. A comparison of momentum fluxes computed by eddy correlation (direct estimation) with profile and bulk aerodynamic (C _D = 3.9 × 10⁻³, Garratt, 1977) methods revealed that though the nature of variation of the fluxes by all these methods is almost similar, both the indirect methods give an under-estimated value of the fluxes. The drag coefficient is estimated as a function of wind speed and surface stability by a multiple regression approach. An average value of the estimated drag coefficient is found to be of the order of 5.43 × 10⁻³. The estimated value ofC _D is validated with a set of independent observations and found to be quite satisfactory. The recomputed momentum fluxes by bulk aerodynamic method using the estimated drag coefficient are in close agreement with the directly estimated fluxes.     

四川西部地区地震活动的空间分维特征

本文采用多分形的方法研究了四川西部地区20年来的地震活动的空间分布特征.对D_q谱与D_(-1),D_(-2)曲线结合震例进行分析,指出其变化与强震活动有密切联系。并结合空区理论,认为D_q(q<0)主要描述了地震空区的情况,该方法在地震前兆信息提取有中重要意义。     

云南省传染病与太阳活动关系的考察

从日地关系的角度出发,探讨太阳活动对人类流行性疾病的影响。根据云南地区自建国以来的１５种流行性疾病每年人数的资料,对每种疾病人数的相对比率与太阳黑子相对数对应作图比较,并求其相关系数。考察结果为：猩红热、疟疾、炭疽、百日咳、白喉、流感、乙脑、痢疾、麻疹、脊髓灰质炎、姜片虫病、肝炎与太阳活动的关系不明确,伤寒、斑疹伤寒和流脑与太阳活动显著相关