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891.
892.
与角岩有关的矿床主要类型及其对深部找矿的意义 总被引:2,自引:0,他引:2
作为热接触变质的产物,角岩在石墨、硅灰石、红柱石等变质成因非金属矿床和各种金属矿床以及油气矿藏均可见,但对其调查研究成果并不多。在文献综述的基础上,结合在南岭、冈底斯等重要成矿带地质找矿的实践,通过对与矿产资源有关的角岩广义概念的界定,概述了与角岩有关的各主要类型矿床的地质特征,如石墨、硅灰石、红柱石等变质成因非金属矿床,钨、钼、铁、铜、铀、金、铅锌、锡、银和稀有金属矿床以及油气矿藏;举例阐述了近年来角岩发育矿区深部找矿中的新突破,如江西淘锡坑钨矿,广西大厂铜坑至拉么一带的锡多金属矿床,西藏甲玛铜多金属矿,云南老厂银铅锌矿、羊拉铜矿、雪鸡坪铜矿等矿区;讨论了角岩型矿床成矿预测的准则。结果表明:矿区和矿田大比例尺深部预测时应注意岩石组合、干湿关系、封闭与开放体系、岩石物性和分带性、原岩岩性及其空间配置关系;区域性中、小比例尺成矿评价时应注意角岩的空间分布、岩石学特征与矿产资源的专属性关系等;利用角岩预测隐伏岩体的应用前景广泛,在深部找矿中具有现实意义。建议加强角岩与成矿关系的理论研究,对以往地质填图工作中发现的"角岩化带"可重新评价其与成矿的关系。 相似文献
893.
A study on the effects of the surrounding faults on water loss in the Zoige Wetland, China 总被引:1,自引:1,他引:0
The Zoige wetland is the biggest alpine wetland in the world,and an important water resource of the Yellow River.Due to natural and human factors,the Zoige wetland has been seriously degraded.Existing studies on the Zoige wetland mainly focus on the macro features of the wetland,while the influence of the surrounding faults on the Zoige wetland degradation is rarely studied.This study uses terrain data to analyze the cover change and the water loss caused by the Wqie-Seji fault based on the distributed hydrological model.The simulated water loss demonstrates that the Normalized Difference Vegetation Index(NDVI) is the most important factor for inducing water loss.The fault is also a factor that cannot be neglected,which has caused 33% of the wetland water loss.Therefore,it is of importance to study the influence of the fault on the wetland degradation. 相似文献
894.
为研究工作区埋汗哈达组储层砂岩的成岩作用特征,以额济纳旗地区东南部杭乌拉和埋汗哈达2条实测剖面为例,根据薄片、阴极发光、X衍射、包裹体测温、扫描电镜等资料,并结合有机地球化学测试资料进行了综合分析。结果表明,该区埋汗哈达组储层砂岩主要成岩作用有压实作用、胶结作用和溶蚀作用,成岩阶段处于中成岩A期;早期的压实作用和胶结作用是使原生孔隙遭受破坏的主要成岩作用,后期的溶蚀作用是形成次生孔隙的重要因素,溶蚀作用在一定程度上改善了储层物性,对油气成藏具有重要意义。 相似文献
895.
内蒙古西部额济纳旗及邻区上石炭统—下二叠统阿木山组火山岩的地球化学特征 总被引:2,自引:1,他引:1
分析了上石炭统小独山阶—下二叠统紫松阶阿木山组玄武岩地球化学特征,对玄武岩类型、岩石特征、构造环境等进行了探讨,结合前人的研究成果,阐述了石炭纪—二叠纪盆地的基本性质。Zr/TiO2-Nb/Y、SiO2-TFeO/MgO和Zr-Y-Nb图解显示,玄武岩类型主要为亚碱性的拉斑玄武岩;稀土元素球粒陨石配分模式为右倾曲线,(La/Yb)N值较高,轻重稀土元素分馏较强,(Gd/Lu)N值相对较低,重稀土元素分馏较弱,δEu在0.87~1.11之间,无明显Eu异常;N-MORB标准化的微量元素蛛网图显示,K2O、Rb、Ba、Th等不相容元素富集,Hf、Nb、Y等亏损。Zr-Zr/Y和Ta/Hf-Th/Hf构造环境图解表明,该玄武岩产于陆内裂谷,指示晚石炭世—早二叠世额济纳旗及其邻区已进入了陆内演化阶段,为拉张作用下的陆内裂谷(裂陷)盆地。 相似文献
896.
卡姆斯特煤矿区煤炭资源储量丰富,但煤田地质工作程度低,勘探开发滞后,已不能适应阿勒泰地区经济发展对矿产开发的需求。为缓解阿勒泰地区煤炭紧缺状况,依据勘探程度、构造复杂程度、煤层露头线及煤层1 000m深部界线等因素圈定三巴斯陶、塔哈拉巴斯塔乌、喀拉萨依等3个含煤远景区作为煤炭资源评价单元,将资源条件、开采技术条件、开发条件和开发效益等影响煤炭资源评价的要素细化为29个评价参数,运用层次分析法(AHP)建立煤炭资源评价模型,构建对比矩阵,确定评价参数权值总排序。根据各评价对象的调查成果,结合专家意见给出各参数隶属度权值,利用乘积法得出评价对象的综合评价隶属度:三巴斯陶为0.627 5,塔哈拉巴斯塔乌为0.700 5,喀拉萨依为0.682 7。根据该结果,认为塔哈拉巴斯塔乌含煤远景区煤炭资源综合条件较好,可作为下一步勘查工作的首选区。 相似文献
897.
Thirty typical soil profiles were sampled in Yangtze River Delta (YRD) region and analyzed for stable lead (Pb) isotopes and
total concentrations of Pb and scandium (Sc). Pb isotopic compositions of A-horizon and C-horizon and Pb/Sc ratio were combined
to estimate the amounts of endogenous and exogenous Pb accumulated in topsoil and identify possible sources. The results indicated
that Pb exhibits a trend of accumulation in topsoil at regional scale. The isotopic composition of endogenous Pb is characterized
by a narrow range of isotope ratios, varying with parent material, while that of exogenous Pb is characterized by a comparatively
wide range of isotope ratios, varying with anthropogenic source. Coal combustion is probably the most important anthropogenic
source of exogenous Pb in the soils of YRD region, as identified by isotopic ratio cross-plot combined with multi-elemental
approaches. 相似文献
898.
The Thornthwaite Memorial, Synthetic, and Carnegie Ames Stanford Approach (CASA) models, with inputs from SPOT-VGT-S10 NDVI
data, meteorological data (precipitation, temperature, solar radiation), and land use data were used to estimate the values
of net primary productivity (NPP) from 1999 to 2007 in China’s Shiyanghe Basin. The human appropriation of NPP, which represents
the difference between potential NPP predicted using the climatic models and actual NPP calculated using the CASA model, served
as the indicator of human intervention in the evolution of productivity of the land. Analysis showed that 78.9% (~9,172 km2) of the degradation occurring in the Shiyanghe Basin was caused by human activities versus 15.0% (~1,752 km2) that was caused by climatic factors, whereas 16.9% (~6,404.5 km2) of the vegetation restoration resulted from human activities versus 49.7% (~18,881 km2) that resulted from climate changes. Human activity played a key role in vegetation restoration in the central areas of the
basin and in determining land degradation in the southwestern and northeastern areas. In addition, climate significantly controlled
the vegetation restoration in the southwestern and northeastern areas and controlled land degradation in the central area. 相似文献
899.
Anthony Snider Jeffery HillShanhong Luo Bob BuergerJim Herstine 《Ocean & Coastal Management》2011,54(8):612-620
This study determined the characteristics of North Carolina Coastal Reserve and North Carolina National Estuarine Research Reserve (jointly referred to as Reserve) visitors, visitor opinions of site conditions, visitor understanding of site management objectives, and patterns of visitation. The latter were investigated to obtain a proxy of place attachment and its effects on knowledge of ownership and perceptions of management. Data were collected on demographics, use patterns, visitor perceptions, and visitor knowledge during the period of 25 May-28 October, 2007. Visitors were educated, wealthy, older, racially homogeneous, and frequent returnees. The majority of respondents supported existing management activities and the implementation of additional use restrictions should site conditions deteriorate. Data indicated that respondents were unaware of which agency manages the Reserve sites or its mission. These findings suggest that management needs to engage in more education of the visiting public. Sensitizing the public to the mission of the Reserve and increasing place attachment could decrease negative visitor impacts. 相似文献
900.
世界遗产地旅游解说系统规划与构建研究——基于安阳殷墟的调查数据 总被引:1,自引:0,他引:1
遗产地旅游解说系统规划是一项综合而又技术性很强的工程。随着河南世界文化遗产数目的增多,遗产地的旅游解说系统的构建就显得尤为重要,它为游客进行深度的文化解读提供了帮助。采用实地访谈和问卷调查的研究方法,系统全面地介绍了安阳殷墟文化遗产景区解说系统现状,并结合旅游解说系统规划的基本模型所关注的六大要素,提出未来安阳殷墟景区应进行科学系统的理念规划和形象设计、解说系统空间布局规划和分级解说服务系统规划,并注重对游客心理和行为的研究。 相似文献