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本文从分析鄂境秦巴山区农业自然条件着手,着重论述光、热、水、土等农业自然条件对发展立体农业的有利因素和限制因素。在揭示自然结构分异特征的基础上,探讨划分山区农业自然资源地带,从而进行山区农业布局的宏观立体设计。 相似文献
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太原市深层孔隙水具有明显的水化学分带性,具体表现为由山前到盆地依次分布硫酸一重碳酸型水、重碳酸一硫酸型水、重碳酸型水,且各类地下水均大体在南北向上呈条带状展布,这与补给水的水化学状况密切相关．利用地球化学模拟软件PHREEQC建立一系列地下水混合模型对深层孔隙水的水化学形成过程进行模拟,结果显示：盆地北部的深层孔隙水受到北部边山岩溶水、盆地北部浅层孔隙水、汾河水的补给,其中北部边山岩溶水是最主要的补给源;盆地西部的深层孔隙水由西部边山岩溶水与盆地西部浅层孔隙水混合而成;盆地南部的深层孔隙水则由盆地北部与西部的深层水混合而成．混合作用是控制区域水化学状况的最重要的因素． 相似文献
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Origin and Distribution of Groundwater Chemical Fields of the Oilfield in the Songliao Basin, NE China 总被引：1，自引：0，他引：1
JIN Aimin LOU Zhanghu ZHU Rong CAI Xiyuan GAO Ruiqi Department of Water Conservancy Ocean Engineering Zhejiang University Hangzhou Zhejiang China Petrochemical Corporation Beijing Exploration Bureau CNPC Beijing 《《地质学报》英文版》2005,79(5):688-696
There are many factors affecting the chemical characteristics of groundwater in the forming process of groundwater chemical fields, such as freshening due to meteoric water leaching downwards, freshening due to mudstone compaction and water release, concentration due to infiltration and freshening due to dehydration of clay minerals. As a result, the groundwater chemical fields are characterized by lengthwise stages and planar selectivity. The former arouses vertical chemical zonality of groundwater. Five units could be identified downwards in the Songliao basin： （1） freshening zone due to downward-leaching meteoric water, （2） concentration zone due to evaporation near the ground surface, （3） freshening zone due to mudstone compaction and water release, and concentration zone due to compaction and infiltration, （4） freshening zone due to dehydration of clay minerals, and （5） filtration-concentration zone; whereas the latter determines the planar division of groundwater chemical fields： （1） the freshening area due to meteoric water, asymmetrically on the margin of the basin, （2） the freshening area due to mudstone compaction and water release in the central part of the basin, （3） the leaky area, which is a transitional zone, and （4） leakage-evaporation area, which is a concentration zone. In the direction of centrifugal flows caused by mudstone compaction in the depression area, the mineralization degree, concentrations of Na^＋ and Cl^-, and salinity coefficient （SC） increase, while concentrations of （CO3^2- ＋HCO3^-） and SO4^2-, metamorphism coefficient （MC） and desulfuration coefficient （DSC） decrease. However, all these parameters increase in the direction of gravity-induced centripetal flows. 相似文献
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豫西一带含煤地层中的滑动构造相对发育。滑动构造引起煤层顶底板附近岩石力学性质发生变化,进而影响岩体的分带性。从研究嵩山井田滑动构造的分布范围、滑体的组成和滑动形态入手,采用岩石特征研究、构造形态分析和岩体质量指标（RQD）定量等研究方法,对影响二1煤层顶板的工程地质条件进行了分析,划分出三个不同工程地质性质的分带：岩体正常带、构造影响带和破碎带．并对各分带的岩体特征进行详细论述,为今后煤矿的安全开采提供了依据。 相似文献
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Chongwen Yu 《地学前缘(英文版)》2011,2(4):551-569
By applying the ‘theory of synchronization’ from the science of complexity to studying the
regional regularity of ore formation within the Nanling region of South China, a characteristic
target-pattern regional ore zonality has been discovered. During the early and late Yanshanian epoch
(corresponding respectively to the Jurassic and Cretaceous periods), two centers of ore formation emerged
successively in the Nanling region; the former is mainly for rare metals (W, Sn, Mo, Bi, Nb) and one rareearth
element (La) and was generated in the Jurassic period; whereas the latter is mainly for base metals
(Cu, Pb, Zn, Sb, Hg), noble metals (Au, Ag), and one radioactive element (U) and was generated in the
Cretaceous period. Centers of ore formation were brought about by interface dynamics respectively at the
Qitianling and Jiuyishan districts in southern Hunan Province. The characteristic giant nonlinear targetpattern
regional ore zonality was generated respectively from the two centers of ore formation by the
spatio-temporal synchronization process of the Nanling complex metallogenic system. It induced the
collective dynamics and cooperative behavior of the system and displayed the configuration of the regional
ore zonality. Then dynamical clustering transformed the configuration into rudimentary ordered coherent
structures. Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional
ore zonality and determined their localization and distribution. The integral successive processes of
synchronization-dynamical clustering-phase dynamics accomplished the regional ore zonality by way of
“multiple field dynamics” of spatio-temporal superposition of multiple coupled pulsatory solitary wave
trains of the zonal sequences of different ores. A new methodology for revealing regional ore zonality is developed, which will encourage further investigation of the formation of deep-seated ore resources and
the onset of large-scale mineralization. 相似文献
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元素的地球化学性状,对成岩成矿作用具有极其重要意义和找矿指示作用。本文根据惯用的以变价元素Fe为标准,拟定成矿地球化学氧化还原环境及其应用;利用元素近似电离能确定成矿介质的酸碱度变化趁势;采用原生晕元素轴向分带序列了解矿床剥蚀程度,进行深部预测与评价。以会理岔河锡矿为例进行分析。以野外可操作性指示成矿作用和找矿勘探工作。 相似文献
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川西北高原山地灾害垂直地带性 总被引：2，自引：0，他引：2
由于形成山地灾害的多种自然因素具有垂直地带性,尤其作为主要动力因素的水,超过一定高度后由液态成为固态,从而也造成了山地灾害的垂直地带性,从高到低可分为冰雪型、冻融型和流水(含地下水)型等三个山地灾害垂直带,高低两带之间主体界线在川西北高原地区为4900m和3500m。各带均有其特有的山地灾害,其中冰雪型山地灾害主要有冰崩、雪崩、冰面湖崩决等;冻融型山地灾害有冻融土流、冻融滑塌、冻融坍塌、融冻泥流、寒冻岩屑流和冰湖溃决等;流水型山地灾害有滑坡、崩塌、泥石流、山洪、泥石流坝和滑坡坝溃决等。认清这些灾害分布的垂直地带性,对于在相应地带进行资源开发和经济建设时,避免、减轻或妥善处治其危害具有重要的现实意义。 相似文献
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中国天山积雪雪崩站区的地理环境 总被引：15，自引：0，他引：15
中国天山积雪雪崩站站区自然地理垂直地带完整。降水丰富，最大达１１４０．８ｍｍ。冬半年降雪量占年降水量的３０％左右。积雪深度多年平均８０ｃｍ。深厚的积雪使站区每年冬季都发生雪崩和风吹雪灾害，成为天山大陆性雪崩研究的天然场所。同时，站区生态与环境良好，植被、土壤种类集天山之大成。站区旅游资源引人入胜。北有“东方阿尔卑斯”之称的乔尔马；南有巴音布鲁克天鹅湖，均由天山公路与本站相连通。 相似文献