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Kunming Basin locates middle of Yunnan altiplano and has a particularity in geography,topographic and geological environment.With the urban dilation quickly,add the reason of the unreasonable city layout,conflicts between environment and urban resources consumption become shrill increasingly.It is human being activities that lead to vulnerability and depravation of geological environment in local.Take a few examples on geological environment to expatiate relationship between urban construction and geological environment carrying capacity,and find a way how to make a better plan for urban sustainable development to achieve new balance between man and nature in local.  相似文献   
2.
The process and path of retrometamorphism of coesite have great significance to our understanding of the P-T tracks of the exhumation of ultrahigh-pressure metamorphic rocks. Most of the coesites in the eclogite from Shima, Anhui Province, the Dabie Mountains, China, are found degraded to quartz partly or wholly, with ruptures occurring in the shells, outside which include the coesite and quartz. According to the microscopic observation, the sample of coesite inclusion is composed of garnet, quartz and coesite, based on which we have built a three-shelled composite sphere model to compute the transition of coesite. Based on the crystal growth formulas and pressure conditions of the ruptures in the garnet, we have calculated the radius of the quartz sphere, which depends on temperature, and eventually drawn the different retrometamorphic paths for different retrometamorphism rates.  相似文献   
3.
化探样品中金、铋、钼化学光谱法联测   总被引:1,自引:0,他引:1  
毛英 《四川地质学报》2001,21(3):190-192
介绍了一种应用化学光谱法对化探样品中痕量金、铋、钼进行联测的方法。该方法是先将试样焙烧后,用王水溶解样品,在盐酸介质中用活性炭静态吸附痕量金、铋、钼,并与其它元素发生分离,再将吸附了待测元素的活性炭灰化后装入电极板,进行光谱测定。生产实践表明,该方法快速、准确,能够进行三元素联测,进一步改进测试工艺,还可进行多元素联测。  相似文献   
4.
丽江高美古的气象条件   总被引:7,自引:0,他引:7  
综述云南丽江高美古的天文台选址经过、自然环境、云量、大气水汽积分含量和其他气象要素观测的结果  相似文献   
5.
Fluid inclusions at a nano to sub-micron scale in quartz from jadeite quartzite at Shuanghe, Dabie Mountains, have been investigated by using the transmission electron microscopy (TEM). Most fluid inclusions are spherical or negative crystal shaped, forming wide swarm-like trails. The TEM reveals that the relationship between coesite and the host quartz is syntaxic and provides strong evidence of the occurrence of high-salty fluids at peak metamorphic conditions. The fluid inclusions are often connected to dislocations, which are undetected at the scale of optical microscopy. Non-decrepitation leakage of fluid inclusions may occur by pipe diffusion of molecule H2O or CO2 along dislocations from the inclusions into the host quartz, thus leading to original inclusion density and composition changes. It should be taken into full account for the correct petrological interpretation of micro-thermometric results.  相似文献   
6.
阳储岭斑岩钨钼矿床的成因特点是物理化学条件多变,同化作用和混杂作用较强。其工业矿物有白钨矿和辉钼矿,其共生矿物以金属硫化物为主。钨钼矿物及其共生矿物与矿床的成因密切相关。  相似文献   
7.
利用热重-质谱联用仪(TG-MS)和多晶XRD对水热法制备的Mg-Al水滑石纳米晶的热分解行为进行表征研究表明:Mg-Al水滑石的热性能与其晶体化学特征有密切的关系。Mg-Al水滑石的热分解过程可分为4个阶段:①T≤280℃时,失层间H2O;②T=280℃~380℃时,失层板中[Mg—OH—Al]结构单元OH-;③T=380℃~580℃时,失层板中[Mg—OH—Mg]结构单元的OH-;④T=395℃~580℃时,层间CO32-逸出。后两个阶段有较大重叠性。[Mg—OH—Mg]中OH-和CO32-最大逸出量对应的温度明显不一致。[Mg—OH—Mg]中OH-的逸出是导致层状结构破坏的诱因,热分解的阶段性随升温速率提高而表现得明显。Mg-Al水滑石的热分解行为受扩散控制。  相似文献   
8.
This paper discusses the geological characteristics and architectures of sequence boundaries and their vicinities and has proposed a classification scheme for the sequence boundaries, which can thus be grouped into three types and eight categories: type I includes exposed truncated surface, palaeosol surface, palaeokarst surface and exposed surface; type Ⅱ boundaries include structural transitional surface during sea-level fall and transgressive onlap surface; and type Ⅲ includes submarine erosional diagenetic diastem and event surface. A study has been made for the three major boundaries lying between the Permian and pre-Permian, the Permian and Triassic, and the Middle and Lower Triassic respectively in terms of multiple disciplines such as lithostratigraphy, biostratigraphy, magnetostratigraphy and carbon and oxygen isotopic geology. These three boundaries are ascribed to type I , typeⅡ and typeⅢ, respectively.  相似文献   
9.
丽江高美古的天文观测条件   总被引:6,自引:0,他引:6  
综述对丽江高美古的视宁度、天光亮度、消光系数进行观测的原理、仪器、观测方法和结果.结果表明,高美古是我国南方的优良光学天文台址,视宁度达到世界优良台址的水平  相似文献   
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