Source parameters of microearthquakes at Mount St Helens (USA)   总被引：1，自引：0，他引：1  

Giuseppina Tusa  Alfonso Brancato  Stefano Gresta  Stephen D. Malone 《Geophysical Journal International》2006,166(3):1193-1223

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Shear wave splitting changes associated with the 2001 volcanic eruption on Mt Etna     

Francesca Bianco  Luciano Scarf&#;  Edoardo Del Pezzo  Domenico Patanè 《Geophysical Journal International》2006,167(2):959-967

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Late Early Miocene lake deposits near Mauensee, central Switzerland: Fish fauna (otoliths, teeth), accompanying biota and palaeoecology     

Jürg Jost  Daniel K?lin  Tanja Schulz-Mirbach  Bettina Reichenbacher 《Eclogae Geologicae Helvetiae》2006,99(3):309-326

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韧性剪切变形对岩石地球化学行为的制约——以北阿尔金巴什考供韧性剪切带为例   总被引：6，自引：0，他引：6  

戚学祥李海兵  吴才来陈松永 《地质通报》2005,24(3):252-257

韧性剪切变形对岩石地球化学行为的制约一直是地质学家们探讨的课题。本文以构成北阿尔金红柳沟——拉配泉俯冲碰撞杂岩带与北阿尔金地块边界的巴什考供斜向逆冲型韧性剪切带为例，通过对韧性剪切带内花岗岩变形前后不同变形强度构造岩的地球化学组成进行对比，确定等比线斜率，探讨韧性变形对岩石体积和成分变异的影响。计算结果表明，在糜棱岩化过程中，糜棱岩化花岗岩体积亏损21％，花岗质糜棱岩体积亏损31％。质量平衡计算结果和等比线图表明，韧；陛剪切作用导致SiO2，流失量最大，A12O3、K2O及Ba、Rb、Sr等都有不同程度的丢失，显示出较强的活动性，MnO、P2O5、Sc位于等比线上或附近，表现出相对的稳定性。岩石中活动组分的变异是流体渗滤作用引起的，不活动组分的变异是体．积亏损造成的。  相似文献   

Soluble organic compounds in fog and cloud droplets: what have we learned over the past few years?     

Sandro Fuzzi  Maria Cristina Facchini  Stefano Decesari  Emanuela Matta  Mihaiela Mircea 《Atmospheric Research》2002,64(1-4)

We have recently set up a new procedure for characterising the water soluble organic compounds (WSOC) in fog water, for which information is still rather limited. Fog samples collected during the 1998–1999 fall–winter season in the Po Valley (Italy) were analysed following this procedure, which allows a quantitative determination of three main classes of organic compounds (neutral species, mono- and di-carboxylic acids, polycarboxylic acids), together accounting for ca. 85% of the total WSOC. This procedure also provides information on the main chemical characteristics of these three classes of compounds (functional groups, aliphatic vs. aromatic character, etc.). The enhanced chemical knowledge on fog/cloud chemical composition opens new scenarios as far as chemical and microphysical processes in clouds and fogs are concerned.  相似文献   

Characterization and migration of atmospheric REE in soils and surface waters     

Dominique AubertPeter Stille  Anne ProbstFrançois Gauthier-lafaye  Laurent PourcelotMireille Del nero 《Geochimica et cosmochimica acta》2002,66(19):3339-3350

Rainwater and snow collected from three different sites in France (Vosges Mountains, French Alps and Strasbourg) show more or less similar shapes of their REE distribution patterns. Rainwater from Strasbourg is the most REE enriched sample, whereas precipitations from the two mountainous, less polluted catchments are less REE enriched and have concentrations close to seawater. They are all strongly LREE depleted.Different water samples from an Alpine watershed comprising snow, interstitial, puddle and streamwater show similar REE distributions with LREE enrichment (rainwater normalized) but MREE and HREE depletion. In this environment, where water transfer from the soil to the river is very quick due to the low thickness of the soils, it appears that REE in streamwater mainly originate from atmospheric inputs. Different is the behaviour of the REE in the spring- and streamwaters from the Vosges Mountains. These waters of long residence time in the deep soil horizons react with soil and bedrock REE carrying minerals and show especially significant negative Eu anomalies compared to atmospheric inputs. Their Sr and Nd isotopic data suggest that most of the Sr and Nd originate from apatite leaching or dissolution. Soil solutions and soil leachates from the upper soil horizons due to alteration processes strongly depleted in REE carrying minerals, have REE distribution patterns close to those of lichens and throughfall. Throughfall is slightly more enriched especially in light REE than filtered rainwater probably due to leaching of atmospheric particles deposited on the foliage and also to leaf excretion.Data suggest that Sr and Nd isotopes of the soil solutions in the upper soil horizons originate from two different sources: 1) An atmospheric source with fertilizer, dust and seawater components and 2) A source mainly determined by mineral dissolution in the soil. These two different sources are also recognizable in the Sr and Nd isotopic composition of the tree’s throughfall solution. The atmospheric contributions of Sr and Nd to throughfall and soil solution are of 20 to 70 and 20%, respectively. In springwater, however, the atmospheric Sr and REE contribution is not detectable.  相似文献   

新时期我国区域经济地理学发展问题初探   总被引：4，自引：0，他引：4  

刘曙光 《地域研究与开发》2002,21(2):1-4

我国新时期的区域经济地理学在取得全面发展的同时，在理论体系，研究方法和实践领域等方面还需要进一步的发展，文章根据学习和实践区域经济地理学的体会，初步提出基础理论和应用理论，思维方法和技术方法等方面发展见解，并指出区域创新系统和国际经济技术合作等学科应注意拓展的重要实践领域，最后提出我国区域经济地理学科发展的建议。  相似文献   

华南地区凉果加工业与凉果资源的匹配关系分析——以广东省新兴县为例     

刘一明  胡新艳  牛宝俊 《地域研究与开发》2002,21(2):60-63

文章以广东省新兴县为例，从凉果资源分布与加工能力的匹配关系角度对华南地区凉果资源的分布，凉果加工业的分布与布局，凉果市场分布与竞争力，凉果加工业与资源的匹配关系等进行了分析，并针对华南地区凉果加工业面临的主要问题提供了一些建议。  相似文献   

成都市民消费结构与休闲活动关系研究   总被引：6，自引：0，他引：6  

杨国良 《地域研究与开发》2002,21(2):77-80

城市居民消费水平，消费结构会影响其休闲消费能力，消费意愿，消费方式，消费态度和休闲时空结构，文章以成都市7个城区歌舞，茶棋牌，电影及城市公园休闲活动调查为基础，探讨了城市居民消费结构及其变化与休闲活动特征的关系。研究结果表明，城市居民消费结构的改变对歌舞，茶棋牌娱乐活动影响最大。  相似文献   

南水北调中线工程建设与河南水资源可持续利用   总被引：2，自引：0，他引：2  

赵永江  刘荷芬  贾虎 《地域研究与开发》2002,21(2):85-88

文章通过对河南省水资源开发利用现状，存在的主要问题，水资源供需平衡以及南水北调工程对河南省水资源利用的影响论述，提出了在拟定南水北调工程供水方案中，应通过强化节水，加强水资源保护，严格控制地下水开采，将水资源作为商品等措施，促进河南省水资源的可持续开发利用。  相似文献