应用地理信息系统(MAPGIS)进行名优作物种植适宜区规划

利用地理信息系统对赣南全区的名优作物（烟草、茶叶）种植适宜区进行规划研究,取得了令人满意的成果。作者在文中具体介绍了ＭＡＰＧＩＳ的应用过程,包括基础信息的预处理、空间数据模型的建立、数据检索、空间分析及获取的最终成果等。     

城市地质信息系统建设的目标与解决方案

城市地质信息系统建设的基本功能目标是：支持多源异构地质空间数据的存储、管理、提取、传输与交叉访问,实现地下地质结构与关系的表达、分析和过程的三维可视化,支持政府决策并开展相关领域的信息社会化服务。为此,应当将其纳入“数字国土”和“数字城市”工程的统一规划中去,一方面借鉴地矿点源信息系统的设计思路与方法,研发并建造主题武的“城市国土资源基础数据平台”,以及相关的决策支持系统和服务应用系统;另一方面运用“多S”集成技术、联邦数据库技术、数据仓库技术、三维可视化技术和计算机网络技术,整合各种已有的和新建的多源异构的数据库、图形库、知识库、方法库、模型库和管理系统、决策系统。在具体设计时,可以将客户机／服务器(C／S)结构与浏览器／服务器(B／S)结构结合起来,并按市(局)—县(区、分局)两级联网的构架进行设置。     

基于车载重力测量平台的城市地下空洞快速探测

为了解决现有静态重力测量在城市地下空洞探测时存在工作难度大、效率低等问题,本文提出了基于车载重力测量平台的城市地下空洞快速探测方法。采用国产高精度捷联式重力仪SAG搭建车载移动重力测量平台,在长春卫星广场附近进行动态重力测量试验。首先对测得数据进行楼房干扰校正;之后采用基于传统极值点深度估计(depth from extreme points,DEXP)方法改进的比值DEXP方法进行重力异常数据深度成像;最后采用Tilt梯度法对位场数据进行边界识别。选取轻轨站附近两条测线进行研究,得出测线在700～1 300m区域附近存在负值异常,在800和1 000m附近最佳深度分别是24和28m,构造指数分别为0.18和0.06;经分析符合实际地下轻轨站空洞类型和所在范围,验证了车载移动平台重力测量在城市地下空洞探测中展开的可能性和有效性。     

运用H、O同位素资料分析地下热水的补给来源——以鲁西北阳谷-齐河凸起为例

通过对阳谷-齐河凸起地下热水的化学成分、同位素及其地热地质条件的分析,对这一地区的地下热水的补给来源进行了研究。本区地下热水的δD为-65‰～-80.67‰,δ18O为-9.2‰～-10.2‰,均分布在全球雨水线的附近,说明该区地下热水主要为大气降水成因。济南北地热田地下热水的补给高程为256m,此范围大致相当于济南南部山区及其以南的泰山北麓;聊城东地热田地下热水的补给高程为411m,此范围大致相当于泰山山脉及其周边的中山区。聊城东地热田地下热水的2H过量参数d明显低于济南北地热田,说明聊城东地热田地下热水的补给区比后者更远。     

Generalized cross-validation for covariance model selection

A weighted cross-validation technique known in the spline literature as generalized cross-validation (GCV), is proposed for covariance model selection and parameter estimation. Weights for prediction errors are selected to give more importance to a cluster of points than isolated points. Clustered points are estimated better by their neighbors and are more sensitive to model parameters. This rational weighting scheme also provides a simplifying significantly the computation of the cross-validation mean square error of prediction. With small- to medium-size datasets, GCV is performed in a global neighborhood. Optimization of usual isotropic models requires only a small number of matrix inversions. A small dataset and a simulation are used to compare performances of GCV to ordinary cross-validation (OCV) and least-squares filling (LS).     

Strain-related differences in the crystal growth of white mica and chlorite: a TEM and XRD study of the development of metapelitic microfabrics in the Southern Uplands thrust terrane, Scotland

Abstract TEM and XRD techniques were used to study crystal growth characteristics of the fabric-forming phyllosilicates which developed in response to low-grade metamorphism and tectonic imbrication in part of the Southern Uplands thrust terrane. Prograde regional metamorphism, ranging from late diagenesis through the anchizone to the epizone, was accompanied by the development of a slaty cleavage which is commonly bedding-parallel. TEM-measured mean thicknesses of white mica and chlorite crystallite populations increase with advancing grade and correlate with XRD-measured crystallinity indices. Analytical TEM data show that prograde changes in composition lead to a net loss of Si, Ca and minor Fe from the fabric-forming phyllosilicates. White micas are paragonite-poor phengites with a mean b lattice parameter of 9.037 Å, and indicate an intermediate pressure series of metamorphism with a field gradient of <25° C km^-1. Chlorite compositions evolved from diabantite (with intergrown corrensite) to ripidolite over an estimated temperature range of 150–320° C. Field gradient and temperature estimates suggest that crystal growth and fabric development occurred at burial depths ranging from 6 km to at least 13 km in the thrust terrane. During late diagenesis, crystal growth of white mica and chlorite was predominantly a consequence of polytypic and phase transitions, and resulted in similar size distributions which resemble typical Ostwald ripening curves. Under anchizonal and epizonal conditions, white mica grew more rapidly than chlorite because of its greater ability to store strain energy and recover from subgrain development; as a result crystal thickness distributions are not typical of Ostwald ripening. In contrast, chlorite crystals which grew under these conditions developed subgrain boundaries at high strain rates which were only partially recovered at low strain rates; these retained dislocations reduce the crystallite thicknesses detected by TEM and XRD, compared with those of white mica. These differences in strain-induced crystal growth indicate that white mica (illite) and chlorite crystallinity indices are likely to show significant differences where low-grade metamorphism is closely associated with tectonic fabric development.     

航磁ΔT解析信号确定线性构造隐伏形态的算法及阿尔金的应用

本文研究了模拟线性地质构造具有普遍意义的有限延深薄板状体ΔＴ的解析信号强度与其几何参数之间的超定方程关系,运用奇异值分解和广义逆技术求解超定方程,获得了高精度的理论反演方法,同时给出了定性解释板状体产状的辅助方法。对阿尔金地区隐伏断裂形态的反演结果,为西藏地体的“北推东移”提供了定量化的地球物理解释证据。文章还勾画了阿尔金与塔里木的深部界线。     

遗传规划在岩石力学中的应用

本文探讨了遗传规划这一新的优化方法在岩石力学参数确定中的应用。由于影响岩石力学性能的各因素之间关系不明确,而遗传规划特别适用于各影响因素之间因果关系不明确的复杂非线性问题。它为预测岩石力学性能提供了一条新的技术途径。通过例子,说明该方法的实用性。     

灰色聚类与圈闭优选

含油气圈闭系统是一种信息不完全的灰色系统,赖以评价圈闭系统的各项参数的原始获取和定量化过程都具有很大的不确定性,也就是说,这些评价参数都是灰参数,灰色聚类恰恰是解决这种确定性差的多参数评价问题。文中探讨了白化函数的构造方法,指出针对不同约束性能参数,白化参数的构造方式也应区别对待,并提出一种对比隶属函数方法,可以对多个圈闭进行严格的优劣排序,结果令人满意。     

论太湖平原防治地面沉降的根本途径

本文在地下水开采－水位降落漏斗－地面沉降相关分析的基础上,认为防治太湖平原地面沉降的根本途径在加于强水资源统一规划和管理,加速引用长江水,大力治理水污染,最大限度地压缩地下水开采量。认为以“警戒水位”和“危险水位”作为控制指标,用时空信息系统进行动态管理,是有效的方法。