澜沧大黑山铅锌多金属矿火山地质作用与成矿     

田宗春 《云南地质》2011,30(3):299-304

大黑山矿属老厂矿之南延,两者有较多相似处。而火山地质作用与成矿关系密切,控制成矿空间和时间,亦是成矿物质及热力主要来源。进一步工作将可扩大远景。  相似文献   

层次分析-熵值定权法在城市建设用地适宜性评价中的应用     

王兰化  张莺 《华北地质》2011,34(4):305-312

在前人评价经验的基础上,采用层次分析-熵值定权法和模糊综合评价法进行了建设用地适宜性评价,该定权方法所采用的三标度法在一定程度上解决了传统九标度法难以通过的一致性检验问题,且便于把握打分尺度,可操作性强;建设用地评价要素及因子的变异程度对指标的权重有很大的影响,引入熵值的概念能更合理地确定评价指标的权重。文中以天津中心...  相似文献   

Architecture of turbidite channel systems on the continental slope: Patterns and predictions   总被引：5，自引：0，他引：5  

T. McHargue  M.J. PyrczM.D. Sullivan  J.D. ClarkA. Fildani  B.W. RomansJ.A. Covault  M. LevyH.W. Posamentier  N.J. Drinkwater 《Marine and Petroleum Geology》2011,28(3):728-743

The study of many slope channel systems has led to the development of rules in the form of observations, measurements, and hypotheses. For example, we hypothesize that high abandonment relief can strongly influence the location of the subsequent channel element and will result in an organized channel stacking pattern in which the path of the younger channel element approximates the path of the former element. The rules were developed with the objective of constructing forward models of petroleum reservoirs that are internally consistent, reproducible, and quantifiable. Channelized turbidite deposits can be interpreted to be the product of multiple cycles of waxing-waning flow energy at multiple scales. Systematic changes in the volume and caliber of turbidity flows through time trigger a fall of the equilibrium profile, which drives erosion and sediment bypass across the slope, followed by a rise of the equilibrium profile, which allows deposition on the slope of increasingly mud-rich sediments through time. In most turbidite successions, at least three scales of waxing-waning cyclicity can be interpreted: element, complex set, and sequence. The stacking pattern of channel elements within a complex set-scale cycle tends to be sequential: (1) erosion and sediment bypass; (2) amalgamation of channel elements associated with a low rate of aggradation; (3) a disorganized stacking pattern of channel elements associated with a moderate rate of aggradation; and (4) an organized stacking pattern of channel elements associated with a high rate of aggradation. Stages 1 and 2 may be absent or minor in mud-rich systems but prominent in sand-rich systems. Conversely, stage 4 may be prominent in mud-rich systems but absent in sand-rich systems. Event-based forward modeling, utilizing rules, can produce realistic architectures, such as the four stages described above. Multiple realizations and multiple alternative models can be constructed to quantitatively examine the probability of specific parameters of interest such as pore volume and connectivity.  相似文献   

Auto-covariance estimation of variable samples (ACEVS) and its application for monitoring random ionospheric disturbances using GPS     

Y. Yuan  J. Ou 《Journal of Geodesy》2001,75(7-8):438-447

 Ionospheric variation may be considered as a stationary time series under quiet conditions. However, the disturbance of a stationary random process from stationarity results in the bias of corresponding samples from the stationary observations, and in the change of statistical model parameters of the process. From a general mathematical aspect, a new method is presented for monitoring ionospheric variations, based on the characteristic of time-series observation of GPS, and an investigation of the statistical properties of the estimated auto-covariance of the random ionospheric delay when changing the number of samples in the time series is carried out. A preliminary scheme for monitoring ionospheric delays is proposed. Received: 18 August 2000 / Accepted: 12 April 2001  相似文献   

青藏高原的隆升过程与地球动力学模型研究进展   总被引：8，自引：2，他引：8  

杨立强  张中杰  王光杰  赵爱华  陈东 《地球物理学进展》2001,16(1):70-81

综合对比、分析了现有青藏高原隆升过程和地球动力学模型相关成果，认为：（1）高原岩石圈以多圈层为特征，其内部层圈相互作用复杂，从而导致隆升过程和机制的复杂性以及构造演化的阶段性，高原的隆升是多种机制联合作用的产物，具有多阶段、非均一、不等速的特征；（2）现有地球动力学模式多力求用一种动力学体制对高原整体构造格架和成因演化进行解释，然而，高原的隆升过程、状态和动力学机制具有非线性、非周期性和无序性等特征，其隆升作用存在非线性效应；（3）以数值模拟为手段，开展物理与数学的定量模拟研究，建立组合动力学模型，是青藏高原隆升过程和地球动力学研究中有待深化的重要课题。  相似文献   

海拉尔盆地盐湖及碳酸盐成因   总被引：1，自引：1，他引：1       下载免费PDF全文

郑喜玉  吕亚平 《盐湖研究》1995,3(3):1-10

本文根据野外考察和室内分析资料，全面总结了该区盐湖概况、矿物组成、卤水成分及盐元素的物质来源，提出了碱湖的形成和天然碱的成因机理。  相似文献   

外来饮食文化影响下广州本地居民地方身份建构过程的代际差异   总被引：2，自引：1，他引：1  

罗秋菊  丁绍莲  潘珂 《地理研究》2018,37(9):1762-1774

伴随着地理学的文化转向以及“身体”“情感”视角的引入,饮食文化的空间问题开始引发人文地理学界的关注。借助身份建构过程模型理论（identity process theory, IPT）,依托对38位广州本地人的深度访谈,阐释外来饮食文化对其身份建构过程的影响及代际差异。研究发现,外来饮食文化的涌入引发了老一辈广州人多重的身份危机感,激发他们投身于地方传统饮食文化复兴实践,以对传统的忠诚和坚守来建构其地方身份。而自幼就被外来及本土饮食文化共同包围的年轻人则善于在不同情境下采纳不同文化态度和策略来建构其地方身份,缓解身份危机。该代际差异折射出饮食文化空间政治结构的轮回,而恰恰是这一空间政治的轮回孕育了地方饮食文化的继替。  相似文献   

Perspectives for Hamburg as a port city in the context of a changing global environment     

Iris Grossmann 《Geoforum》2008,39(6):2062-2072

During recent decades, most European river-port cities and also many seaport cities have undergone a major transition towards a service-centred, rather than industrially-based metropolis, offering a high quality urban environment with a revitalised waterfront. Hamburg is one of the few river-port cities that have chosen the course of port expansion instead. This paper discusses the consequences of current global technological, organisational and economic developments for the port. Changing requirements imply rising monetary and land-use costs and environmental and social impacts, and also entail the risk that the port may not be able to fulfil new requirements and could thus lose market shares to coastal competitors. More importantly, the world-wide economic shift towards the service sector has affected port-dependent jobs in two ways: Directly port-dependent jobs have been reduced to a fraction, while many indirectly port-dependent jobs no longer require physical proximity of the port. Those benefits that continue to arise tend to spread over a much larger geographical region, while the port’s costs remain locally concentrated. Given the increasing competition between world-wide metropolitan regions that seek to establish themselves in new sectors and attract a qualified workforce, it is particularly relevant for Hamburg to account for these changes and to incorporate an assessment of the port’s changing costs and benefits into planning processes. To date, this task has received little attention from the city.  相似文献   

A Comprehensive Model for Evaluating Coalbed Methane Reservoirs in China   总被引：3，自引：0，他引：3  

YAO Yanbin  LIU Dameng  TANG Dazhen  HUANG Wenhui  TANG Shuheng  CHE Yao 《《地质学报》英文版》2008,82(6):1253-1270

Coalbed methane reservoir （CBMR） evaluation is important for choosing the prospective target area for coalbed methane exploration and production. This study aims at identifying the characteristic parameters and methods to evaluate CBMR. Based on the geological surveys, laboratory measurements and field works, a four-level analytic hierarchy process （AHP） model for CBMR evaluation is proposed. In this model, different weights are prioritized and assigned on the basis of three main criteria （including reservoir physical property, storage capacity and geological characteristics）, 15 sub-criteria, and 18 technical alternatives; the later of which are discussed in detail. The model was applied to evaluate the CBMR of the Permo-Carboniferous coals in the Qinshui Basin, North China. This GIS-based fuzzy AHP comprehensive model can be used for the evaluation of CBMR of medium-high rank （mean maximum vitrinite reflectance 〉0.5 %） coal districts in China.  相似文献   

不整合结构构造与构造古地理环境 ——以加里东中期青藏高原北缘及塔里木盆地为例   总被引：4，自引：4，他引：0  

何碧竹  焦存礼  许志琴  刘士林  蔡志慧  李海兵  张淼 《岩石学报》2013,29(6):2184-2198

不整合结构与不整合面结构具有不同的属性及特征.本文在分析不整合三层结构的基础上,进一步剖析了平行不整合、角度不整合、异岩不整合等3大类不整合的结构构造,划分出10个具有不同结构特征的不整合亚类.重点针对不整合面下的构造变形特征、不整合结构类型的平面分布、不整合面上的初始沉积物、物源及其层序结构等展开了精细研究,对不同结构类型的不整合形成运动学及动力学进行了初步探讨.并以塔里木盆地志留系与奥陶系不整合为例,在盆地尺度,解析不同区域不整合结构类型的特征、性质及差异.现今保留的志留系与奥陶系不整合在盆地中南部广大地区呈角度不整合,在阿瓦提-满加尔坳陷南部、巴楚隆起中西部、塔中隆起北部为低角度、北倾的单斜角度不整合;在塘古兹巴斯凹陷表现为中-低角度的断褶不整合,呈北东向展布,在巴楚隆起东部及塔中隆起的南部局部也存在北东向展布的断褶不整合.在盆地北部塔北隆起西部局部存在褶皱不整合,东部存在低角度、南倾、单斜不整合.而盆地中部在阿瓦提-满加尔凹陷中北部、塔东凹陷东北则以平行不整合为特征.结合沉积地层发育及构造演化分析,恢复了志留系沉积前构造古地理,塔里木盆地大部分为混积陆棚沉积、中部碳酸盐岩台地被逐渐淹没,满加尔及英吉苏凹陷为盆地相沉积.伴随着盆地南缘西昆仑-库地洋、南阿尔金洋的闭合及碰撞造山,在盆地南部主体为南北向的缩短,塘古兹巴斯凹陷为南东-北西向缩短,且变形强度明显大于南北向的缩短.因此,盆地南部的南东-北西向挤压作用是该期最活跃的构造作用,和田古隆起北部、塘古兹巴斯凹陷北东向加里东期褶皱带西北部,应是塔里木盆地第一期油气大规模运移聚集的有利区,值得进一步探索.本文通过对不同时期不整合结构的解剖,尝试区别分析不同期次构造事件的作用及效应,识别单一构造事件(或构造运动)在构造古地理重建及成藏、成矿中的作用.  相似文献