滇东北山区土地垦殖指数与退耕还林规划

在分析研究该区域基于可持续利用的合理耕地规模基础上,确定了全区及各县（市）合理垦殖指数;采用垦殖合理度和不合理度２个指标定量评价了现状垦殖指数的合理性程度。结合区域土地利用总体规划,制定了该区域退耕还林战略规划方案。     

Distinguishing Carbonate Reservoir Pore Facies with Nuclear Magnetic Resonance Measurements

  Characterization of carbonate rocks may involve identifying the important pore types which are present. In the past, this task has required detailed petrographic analysis of many core samples. Here, we describe a method which uses nuclear magnetic resonance (NMR) measurements to reduce the amount of petrographic analysis needed for porosity typing of carbonate reservoir rocks. For a rock sample which has been measured with NMR, our method decomposes the log(T₂) spectrum into at most three Gaussian-shaped components and gives a set of nine parameters. Two characteristic quantities having geological significance are extracted from the nine parameters. Values of the two quantities are compared with a reference set, established from samples having both NMR and petrographic evaluations of porosity types. We use a Bayesian approach to the classification of the dominant porosity type. Tests of our method on 103 samples show a correct prediction in 60 to 90 percent of the samples. The lower success rate was obtained for samples with five porosity types from three fields; the higher success rate obtained with samples with three porosity types from one well. The use of geologically significant quantities extracted from the decomposition gives comparable success rate to those obtained using a standard, non-geological approach such as canonical variates.     

浅层地震反射波法在石膏矿采空区调查中的应用

随着人们对地下矿产资源的过度开采,地下空间形成了较大区域的采空区。采空区出现后,其上覆岩层平衡条件被破坏,使得上覆岩层产生移动变形,直到破坏、塌落,导致地表建筑物变形、破坏,地表大面积下沉、凹陷,形成大面积的采空塌陷区。采空区的存在使矿山生产面临很大的安全问题。近年来,矿山采空区的危害越来越受到人们的重视,在采空区调查中,各种地球物理方法起到了重要的作用,国内外以往探测实践表明,较为常用的物探测量方法有:高密度电阻率法、瞬变电磁法、CSAMT法、浅层地震反射波法、放射性土壤氡气测量法等,但每种物探方法的应用均具有一定的条件,需要根据岩石物性特征、场地条件、探测深度、环境影响等因素选择合适的地球物理方法。地震反射波法具有抗干扰能力强、分辨率较高等优势,被较多应用于矿山采空区的调查中。该文以临沂市兰陵县某石膏矿采空区为例,采用浅层地震反射波法对该石膏矿采空区进行调查,通过对获得的地震剖面资料进行处理和解释,取得了较好的探测效果,其技术方法可为同类采空区的探测提供借鉴和指导。     

基于流速衰减特征的泥石流冲出距离预测方法

泥石流冲出距离的确定是泥石流灾害评价及防治中的关键环节。基于泥石流在堆积区流速的变化特征,提出了泥石流流速"衰减系数"的概念。通过对泥石流流速衰减系数的定义和计算公式的推导,提出了一种基于泥石流流速衰减系数来确定泥石流冲出距离的新方法,并以四川省泸定县干沟泥石流为实例进行计算和验证。研究结果表明:当干沟泥石流在堆积区的流速大于初始(沟口)流速的15%时,流速的衰减程度极为显著;而当堆积区流速小于初始速度的15%时,流速的衰减极为缓慢。研究结果对泥石流灾害的危险性评价及防灾减灾具有一定的理论和实践意义。     

广东纯石灰岩山区人口外迁后的环境保护与旅游开发设想

分布在广东省西北部的纯石灰岩山区自然资源十分贫乏，自然条件十分恶劣，土地的人口承载力十分低，已采取外迁人口，以求从根本上解决其极端贫困的措施。人口外迁以后的石灰岩山区应继续发展林业，改善生态环境，创造条件建成国家森林公园或自然保护区，并适当发展旅游业，变无用地为有用地。     

山西省煤矿采空塌陷形成机制浅析

煤矿采空塌陷是山西省地质灾害的主要灾种.采空塌陷的发育程度由内因、外因共同决定.自然地理地质环境背景条件为内因,人类工程活动为外因.内因决定了采空塌陷的分布区域,外因则控制它的发育程度.内因通过外因表现出来.     

Empirical‐based out‐of‐plane URM infill wall model accounting for the interaction with in‐plane demand

The role of masonry infills in the seismic behavior of reinforced concrete buildings has been widely studied in terms of their strength and stiffness contribution in the in‐plane (IP) direction, while fewer studies have been carried out on their response and modeling in the out‐of‐plane (OOP) direction. In this paper, the state of the art in code and literature provisions regarding infills' OOP capacity and seismic demand is presented, together with a review of the experimental tests that have been carried out to investigate infills' OOP behavior and the effects of IP‐OOP interaction. This review aims to collect an experimental database that is used to evaluate the effectiveness of literature and code provisions and to propose a semiempirical approach both for predicting infills' OOP strength, stiffness, and displacement capacity and for modeling the effects of IP displacement demand on OOP behavior and vice versa. Then, the state of the art on modeling of infills' OOP behavior and IP‐OOP interaction is presented together with a new macro model based on the proposed formulations and conceived to represent the IP and OOP behavior by taking into account the mutual interaction effects. Finally, the proposed model is used for an example application on two case‐study buildings, showing the effects of taking into account or neglecting the IP‐OOP interaction phenomena.     

煤田三维地震勘探测量的技术方法探讨

以实例介绍了三维地震勘探测量中各项作业限差的关系、复测校差的关系以及测点坐标系转换关系.依照规范及限差控制标准,讨论了控制点布设、导线布设的精度计算以及作业方法.通过对极坐标法误差的计算论证了放样点误差主要是由测角误差引起.     

骊山北坡Ⅰ区坡体病害整治试验工程钻孔工艺

介绍了骊山北坡Ⅰ区坡体病害及整治试验工程中锚索钻孔的一些相关工艺技术。包括锚固工作平台搭设及钻机固定;钻孔工艺选择及机具装置研制;预防锚孔弯曲的措施;破碎带、裂缝带的钻进技术及封孔固壁堵漏技术。     

GPS偏心观测及其精度分析

由于种种条件的限制，在很多情况下GPS天线都无法实现真正的对中，在某些特殊情况下，例如观测站必须与VLBI站或SLR站重合，而又无法在这些站的标志中心安设接收机天线，这就要求进行GPS偏心观测。本文将着重对GPS偏心观测归心元素的测定方法、归心改正数的计算以及归心元素的测定精度进行讨论和分析。