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991.
为促进矿床开发经济意义概略研究工作的规范化,方便地质工作者开展概略研究的需要,开发了矿床开发经济意义概略研究系统(PSDD)。PSDD可生成概略研究要求的所有图表和概略研究报告,给出经济评价指标。图表为.xls格式,概略研究报告为.doc格式。静态经济评价指标包括矿山总利润、投资利润率和投资回收期;动态指标包括财务净现值、财务净现值率、财务内部收益率和动态投资回收期。PSDD通过实际应用,取得了预期的效果。PSDD作为矿床开发经济意义概略研究的工具,将为提升研究水平、规范研究成果、提高研究效率起到积极的作用。但PSDD的应用效果和选取参数的代表性关系密切,使用前应认真进行市场调研。 相似文献
992.
通过岩心、铸体薄片、扫描电镜、物性分析和孔隙图像分析等资料,对高邮凹陷永安地区戴南组一段砂岩储层特征进行了系统分析,从沉积和成岩两方面对储层物性主控因素进行了研究。研究结果表明:岩石类型为长石岩屑砂岩,成分成熟度较低,粒度偏细,分选中等偏差; 储层物性以低孔低渗为主中孔中渗为辅,孔隙类型有粒间孔、粒间溶孔、粒内溶孔和铸模孔,平均孔径为37.53 μm,喉道主要为可变端面的收缩部分,其次为片状和弯片状喉道,平均喉道半径为10.25 μm,孔喉配位数主要为3,分选性好。沉积作用是高邮凹陷永安地区戴南组一段砂岩储层物性主控因素之一,水动力强分选程度高的沉积环境形成的砂岩粒度大分选好,储层物性好; 不同的成岩作用类型对储层物性具有不同的控制作用,压实和胶结作用导致储层孔隙空间变小,物性变差,而溶蚀作用形成次生孔隙空间,储层物性得到改善,在2 500~2 700 m和2 850~2 950 m处形成了明显的次生孔隙发育带。 相似文献
993.
广东云浮高枨银铅锌多金属矿区成矿地质特征及成岩时代研究 总被引:1,自引:0,他引:1
高枨银铅锌多金属矿床是南岭成矿带中新探明的典型构造蚀变岩型矿床之一.矿床控制规模已达中型以上,但研究程度低,成因认识模糊,影响找矿进展.本文根据脉状矿体稳定延伸、主矿脉产于中酸性岩体中、部分矿脉穿切白垩系红层及老变质岩系的宏观地质特征,认为该多金属矿属岩浆期后热液成因,成矿作用发生在晚白垩世至古近纪.通过LA-ICP-MS锆石U-Pb法确定地表含矿岩体的年龄为438.7±0.8 Ma,属于加里东期.因此,地表含矿花岗岩体作为围岩,其形成时代明显早于成矿期,推测矿区深部存在隐伏岩体,隐伏岩体是成矿的主导因素.这一成果为今后找矿方向的调整提供了重要依据. 相似文献
994.
Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago 总被引:15,自引:0,他引:15
LU Huayu WANG Xiaoyong AN Zhisheng MIAO Xiaodong ZHU Rixiang MA Haizhou LI Zhen TAN Hongbing & WANG Xianyan . State Key Laboratory of Loess Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi''''an China . Qinghai Institute of Salt Lakes Chinese Academy of Sciences. Xining China . Institute of Geology Geophysics Chinese Academy of Sciences Beijing China . Department of Geography Qinghai Normal University Xining Chi 《中国科学D辑(英文版)》2004,47(9)
~~Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago~~ 相似文献
995.
Qian Hou Chuanlong Mou Qiyu Wang Zhiyuan Tan Xiangying Ge Xiuping Wang 《Geochemistry International》2018,56(4):362-377
The North Qilian orogenic belt is the key to figure out the evolution and assembly of Asia. The Upper Silurian Hanxia Formation which is deposited in the north area of North Qilian Orogenic Belt is of utmost important to reveal the architecture and orogenic process of the North Qilian belt. So provenance analysis of the Hanxia Formation is of significance to reveal not only that the tectonic evolution of the central orogenic belt China, but also that Paleozoic Asia plate reconstruction. The ratios of elements and some discrimination diagrams based on geochemistry indicate that felsic rocks constitute their main source rocks. The chemical index of alteration is less than 80, indicating that the source rocks are relatively fresh and of low maturity. On the Th/Sc versus Zr/Sc scatter plot, samples from Hanxia Formation occur along the magmatic compositional variation trend of rocks, indicating that the rocks did not undergo obvious sedimentary sorting and recycling. The major and trace elements discrimination diagrams imply that Hanxia Formation rocks were derived from continental island arc. Recent studies show that the North China plate subducted southwards and produced subduction-related arc magmatism along the southern margin of the North Qilian Terrane during the Silurian. Therefore, we infer that in the late Silurian period the subduction-related arc became accreted to the Central Qilian terrane to the south, forming a composite continental arc, and the North Qilian belt accumulated in a fore-arc basin. 相似文献
996.
自20世纪80年代中期以来,GNSS技术在高精度地壳运动观测与构造形变研究中取得了丰硕的成果,为大地测量、地球动力学研究和防震减灾等诸多领域的业务深化和应用拓展提供了强大的技术支撑。本文在回顾中国大陆地壳形变GNSS站网发展历程的基础上,阐述该网络产出的中国大陆长期构造运动速度场、中国大陆应变率场、位移时间序列、基线时间序列和多边形应变时间序列等几类基础产品,分析这些产品在中国大陆构造运动动态趋势和地震预测分析中的应用情况以及所面临的瓶颈问题,最后展望未来GNSS在高精度地壳运动监测应用中的发展方向。以中国大陆构造环境监测网络为基础,大力推进国内海量GNSS观测数据的共享,提升GNSS多系统融合定位精度,将产出更为精细的科学产品,更好地服务于中国大陆地壳运动和地震预测分析等研究。 相似文献
997.
TAN Bing XU Qing ZHANG Yan XING Shuai 《地球空间信息科学学报》2006,9(3):196-200
IntroductionI mage superresolution (SR) refers to i mageprocessing algorithms which can produce highquality ,high-resolution ( HR) i mages froma setof low quality , low-resolution ( LR) i magesthrough fully exploiting the great potentials ofcurrent i mage data , such as the multi-looked,multi-temporal , multi-platformand sequencei m-ages . Considering the additional temporal dataavailable in the i mage sequence ,i mage superres-olution can be more generally considered as aprocedure of transf… 相似文献
998.
Wenjin Sun Yu Liu Gengxin Chen Wei Tan Xiayan Lin Yuping Guan Changming Dong 《海洋学报(英文版)》2021,40(10):17-29
In general, a mesoscale cyclonic (anticyclonic) eddy has a colder (warmer) core, and it is considered as a cold (warm) eddy. However, recently research found that there are a number of “abnormal” mesoscale cyclonic (anticyclonic) eddies associated with warm (cold) cores in the South China Sea (SCS). These “abnormal” eddies pose a challenge to previous works on eddy detection, characteristic analysis, eddy-induced heat and salt transports, and even on mesoscale eddy dynamics. Based on a 9-year (2000–2008) numerical modelling data, the cyclonic warm-core eddies (CWEs) and anticyclonic cold-core eddies (ACEs) in the SCS are analyzed. This study found that the highest incidence area of the “abnormal” eddies is the northwest of Luzon Strait. In terms of the eddy snapshot counting method, 8 620 CWEs and 9 879 ACEs are detected, accounting for 14.6% and 15.8% of the total eddy number, respectively. The size of the “abnormal” eddies is usually smaller than that of the “normal” eddies, with the radius only around 50 km. In the generation time aspect, they usually appear within the 0.1–0.3 interval in the normalized eddy lifespan. The survival time of CWEs (ACEs) occupies 16.3% (17.1%) of the total eddy lifespan. Based on two case studies, the intrusion of Kuroshio warm water is considered as a key mechanism for the generation of these “abnormal” eddies near the northeastern SCS. 相似文献
999.
One-month old Zygophyllum xanthoxylon seedlings were grown under five different Ni concentrations (0, 50, 150, 450 and 900 mg/kg). Growth parameters, tissues Ni accumulation, soluble protein content, photosynthetic pigment content, lipid peroxidation, antioxidative enzyme activities, and proline content were studied after one month of Ni exposure. The significant reduction in fresh biomass in the shoot and roots was detected at high Ni concentrations (≥450 mg/kg), whereas dry biomass was not significantly affected in both organs by any of the Ni doses tested. The Ni contents in the shoots and roots increased in a dose-dependent manner, and Ni contents in roots were higher than that in shoots at all treatments. The high Ni doses elevated soluble protein contents in leaves and roots. No visible symptoms of chlorosis were observed in leaves of plants grown in presence of Ni. Malondialdehyde (MDA) contents significantly increased in leaves and roots at high Ni treatments (≥450 mg/kg), indicating that Ni induces oxidative stress. Enzyme activities might play a central role in cellular protection against the Ni induced oxidative stress. Proline contents proportionally increased with the elevated Ni concentrations. Zygophyllum xanthoxylon revealed moderate Ni tolerance under tested culture conditions, and could be used as tools for revegetation for erosion control in moderate Ni contaminated sites. 相似文献
1000.
赣北大湖塘钨铜多金属矿集区位于扬子板块东南缘、江南造山带中段,是近年来查明的世界级钨矿产地之一。对大湖塘平苗矿段中粗粒白云母花岗岩进行了岩相学、锆石U-Pb年代学、地球化学及成矿作用的研究,结果表明,此花岗岩内白云母显示原生白云母的特性,LA-ICP-MS锆石U-Pb年龄为(145.7±0.6)Ma,与区内细粒黑云母花岗岩测试年龄相近,系同源岩浆演化结晶分异的结果,为燕山期多期次岩浆侵入的第二阶段。燕山期岩石单元先后有似斑状黑(二)云母花岗岩→细粒黑云母花岗岩、白云母花岗岩→花岗斑岩,白云母花岗岩是区内重要的成矿地质体之一。地球化学研究表明,该白云母花岗岩为高分异S型花岗岩,具有高硅(w(SiO2)=73.14%~74.19%)、富碱、过铝质的特征及较高的分异指数,轻重稀土分馏明显,呈左高右低的深V型,Eu表现为强烈的亏损,存在REE四分组效应,Rb/Sr、Rb/Ba的平均值分别为151.81和245.21,表明岩浆是经历多阶段分离结晶、高度分异的结果。 相似文献