南海表层沉积物中钙质超微化石分布特征

为系统描述钙质超微化石在南海表层沉积中的分布特征,对遍布南海的175个样品进行了实验分析。发现不同地区钙质超微化石绝对丰度相差很大,从0—3.8×1010个.g-1不等。平面上将钙质超微化石丰度分为3个区。共鉴定出钙质超微化石21属28种,以Emiliania huxleyi、Florisphaera profunda和Gephyrocapsa oceanica为优势种,其中Florisphaera profunda占据绝对优势。南海钙质超微化石分布具有两个明显特征:一是14°N线南北两边钙质超微化石的分布存在差异;二是南海钙质超微化石丰度以南沙群岛和西沙群岛两片海域为最高,并有东北-西南走向的分布趋势。对影响钙质超微化石分布的水深、上升流与营养盐、陆源物质稀释作用、碳酸盐溶解作用等因素作了讨论,并根据钙质超微化石随水深的变化推测南海碳酸盐补偿深度应在4 000m左右。     

In situ and satellite observations of the eastward migration of the Western Alboran Sea Gyre

During October 2003 an intensive oceanographic survey (BIOMEGA) was carried out in the Alboran Sea, coinciding with a migration event of the Western Alboran Sea Gyre (WAG). The observations gathered during that cruise constitute the first field evidence of a migrated stage of the WAG. In this work we present the main differences between the 3D hydrodynamic fields observed during BIOMEGA and those corresponding to a WAG located at its usual position. The migration of the gyre was followed by satellite (altimetry and sea surface temperature) imagery. The causes of the gyre migration are explored in terms of the quasi-geostrophic tendency equation, in particular of the dynamics governing scales larger than the Rossby radius of deformation. It is shown that the steady state gyre must be almost equivalent barotropic and that the key process to break down the stationarity would be a density advection at gyre scale. The mechanisms to explain the migration of the WAG proposed by previous authors are discussed in light of the explanation proposed in this work.     

THE INTRINSIC ACIDITY CONSTANTS AND SPECIFIC SURFACE AREA OF MARINE SOLID PARTICLESII. THE RELATIONSHIP BETWEEN THE INTRINSIC ACIDITY CONSTANT AND THE TERNARY SURFACE COMPLEX

This paper deals with the infrared spectra of " amino acid- clay , calcium carbonate and y-AlOOH" and " Cu (II )-clay-amino acid" model systems, and shows that the model of the ternary surface complex is M-OHLCu (L = amino acid) for marine solid particle-Cu (II)-amino acid. Study of the formation mechanism of the ternary surface complex shows that the specific surface area , and especially the intrinsic acidity constant, determine whether the ternary surface complex is easily formed, and that factor, FTSC,quantifies the relationship between the promoting effect of organics on Mt-marine solid particle ion exchange and the intrinsic acidity constant and specific surface area.     

蒸发皿中水面蒸发氢氧同位素分馏的实验研究

气象要素与蒸发密切相关,通过室内外不同气象条件下的器皿水蒸发实验,获得了水面蒸发氢氧稳定同位素分馏因子与气象要素的关系。实验结果表明,随着蒸发的进行,剩余水体中逐渐富集重同位素;自由水体蒸发同位素分馏在垂线上有分层现象,表层水体同位素值比垂线平均的同位素值略富集;不同温度条件下的室内蒸发实验中,温度越高,液-气间分馏系数越小,相应于同一剩余水体体积比,剩余水体稳定同位素值则越低。室外器皿水自由蒸发实验中得出的蒸发线方程斜率较大地偏离了当地降水线,表明实验期间水体蒸发分馏作用较明显。该研究为进一步揭示水体蒸发分馏规律提供了可靠的实验依据。     

浅层SH反射波法和多道瞬态面波法 进行联合工程勘察的讨论

针对目前单一工程物探方法调查浅部地质结构的局限性,提出采用弹性波法勘察中研究浅部地质结构的SH波反射勘察和多道瞬态面波法勘察这2种有效手段进行联合勘探,提高其可靠性和精度,并给出了3个实例,指出了在数据采集和处理时应注意的问题。     

基于传统吸附烃概念的烃类检测新技术

烃类是地表油气地球化学勘查地下油气藏的直接指标.目前我国油气化探中常用的酸解烃法检测出的烃类,不应定义为"吸附烃",它是介质吸收的产物,属结合态烃类,应定义为"吸收烃".地表酸解烃异常十分稳定,重现性好,能够很好地证明地质历史上曾经有过的烃类运移过程,但在反映目前深部油气信息方面具有多解性.针对酸解烃法的弱点,依据烃类垂向运移理论和物质吸附作用原理,自行设计开发、研制了一套吸附烃脱气装置,建立了土壤吸附烃提取新技术和检测方法.该方法有利于在近地表获取油气系统的动态信息,强化烃类测量法对其信息源的探测,可以提高地表油气化探预测油气分布的成功率.     

A sub-pixel analysis of urbanization effect on land surface temperature and its interplay with impervious surface and vegetation coverage in Indianapolis,United States

This study developed an analytical procedure based upon a spectral unmixing model for characterizing and quantifying urban landscape changes in Indianapolis, Indiana, the United States, and for examining the environmental impact of such changes on land surface temperatures (LST). Three dates of Landsat TM/ETM+ images, acquired in 1991, 1995, and 2000, respectively, were utilized to document the historical morphological changes in impervious surface and vegetation coverage and to analyze the relationship between these changes and those occurred in LST. Three fraction endmembers, i.e., impervious surface, green vegetation, and shade, were derived with an unconstrained least-squares solution. A hybrid classification procedure, which combined maximum-likelihood and decision-tree algorithms, was developed to classify the fraction images into land use and land cover classes. Correlation analyses were conducted to investigate the changing relationships of LST with impervious surface and vegetation coverage. Results indicate that multi-temporal fraction images were effective for quantifying the dynamics of urban morphology and for deriving a reliable measurement of environmental variables such as vegetation abundance and impervious surface coverage. Urbanization created an evolved inverse relationship between impervious and vegetation coverage, and brought about new LST patterns because of LST's correlations with both impervious and vegetation coverage. Further researches should be directed to refine spectral mixture modeling by stratification, and by the use of multiple endmembers and hyperspectral imagery.     

基于弹性薄板的地表沉陷预计模型

在分析地表沉陷基本规律的基础上,依据弹性薄板理论,建立非充分采动条件下岩层和地表沉陷预计的一类新模型,并推导出地表任意点倾斜、曲率、水平移动以及水平变形的计算公式。该模型充分考虑到地质采矿因素（煤层倾角）及煤层上方各岩层的影响,克服传统预测方法的缺陷,特别是概率积分法关于拐点反对称要求。最后,应用实例证明该方法的应用效果。     

黄土台缘滑坡地表水入渗问题分析

黄土塬区提灌工程保证了农业生产,却造成了地下水位大幅抬升,使得近年来黄土台缘滑坡不断发生。黄土滑坡一个普遍特征就是后缘发育地裂缝以及落水洞,使地表水（灌溉水以及降雨）直接灌入坡体,诱发了大量黄土滑坡。因此,地表水入渗对于黄土滑坡机理研究以及滑坡防治具有重要意义。文章基于对陕西泾阳南塬黄土滑坡的现场调查,对黄土台缘滑坡地表水入渗工程地质问题进行了初步分析,包括：①地表水入渗与落水洞形成机制;②地表水入渗途径及其与黄土滑坡发育过程的关系;③降雨因素对于黄土滑坡的影响程度。     

框架预应力锚杆边坡支护结构的稳定性分析方法及其 应用

以边坡极限平衡理论及框架预应力锚杆边坡支护结构的圆弧滑动破坏模式为基础,在考虑框架、锚杆对土体边坡稳定性影响的情况下,基于圆弧滑动条分法的思想利用积分法建立了内部稳定性安全系数计算模型和最危险滑移面搜索模型。确定滑移面圆心坐标为几何控制参数,推导了安全系数计算模型中各变量与滑移面圆心坐标之间的函数关系式,从而获得了滑移面几何控制参数与内部稳定性安全系数之间的函数关系。利用网格法对框架预应力锚杆支护结构最危险滑移面的圆心坐标进行动态搜索和求解。最后采用Matlab语言编制了框架预应力锚杆边坡支护结构的稳定性分析程序,并结合工程实例进行了验算,讨论了此种方法的适用条件,结果表明该方法简明适用,较传统的经验分析方法更加合理。