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911.
Analysis on geo-effects of China’s overseas industrial parks: A case study of Cambodia Sihanoukville Special Economic Zone 总被引:1,自引:0,他引:1
China's overseas industrial parks contribute to political and economic cooperation,cultural exchange between home and host countries.Current studies mainly discuss the ef-fect of overseas industrial parks from the perspective of institutional and cultural difference,multi-scale coupling,as well as key partnerships,while little attention has been paid to the comprehensive analysis of overseas industrial parks.Based on a theoretical framework,this paper explores the overall effect of China's overseas industrial parks from the geo-effects perspective by using field interviews and a case study approach.The research shows that:(1)the geo-effects reveal the over effect of overseas industrial parks from the multiple and com-plementary dimensions of geopolitics,geo-economics,geo-society and geo-culture;(2)the Cambodia Sihanoukville Special Economic Zone,as a flagship BRI project,has produced the prominent and positive geo-effects;(3)the institutional-economic-cultural-environmental adaptability of overseas industrial parks is becoming important.Overseas industrial parks must be rooted in the politics,economy,society,and culture of host country;embedded in local social networks;balance the rights and interests of all stakeholders;and form the community of interests,community of destiny,and community of responsibility with political mutual trust,economic integration,cultural inclusiveness,and social harmony.The paper not only deepens the understanding about the overall effect of overseas industrial parks,but also provides decision support and theoretical reference for government policy makers and the overseas investment of enterprises. 相似文献
912.
气候变化对中国农业生产影响研究展望 总被引:32,自引:0,他引:32
综述了气候变化背景下中国农业气候资源、农业气象灾害(干旱、洪涝、高温热浪、低温灾害)和农业病虫害的变化趋势与规律,从农业生产潜力变化、作物种植制度变化和作物品质变化等方面阐明了气候变化对中国农业生产的影响事实,分析了气候变化对中国农业生产的可能影响和中国农业生产适应气候变化的对策措施。在此基础上,针对气候变化背景下中国气候资源的时空分布特点及农业生产出现的新情况、新问题,指出了当前中国关于气候变化对农业影响研究存在的不足,提出了未来气候变化对中国农业生产影响研究需要重视的方面,为确保气候变化背景下中国的农业生产安全及粮食安全提供决策支持。 相似文献
913.
914.
915.
鲁西地区是全球完整保存新太古代早期TTG(英云闪长岩-奥长花岗岩-花岗闪长岩)和绿岩带的区域,是研究太古宙岩浆演化类型和太古宙时期壳幔作用以及构造模式的典型区域。本文在野外地质调查的基础上,通过年代学、Hf同位素和岩石地球化学等手段,探讨了鲁西地区新太古代花岗岩和二长花岗岩的地球化学特征和形成背景。鲁西地区新太古代花岗岩和二长花岗岩U-Pb年龄主要为2 537和2 566 Ma。花岗岩(TA1802)εHf (t)值为-1.4~2.9,平均值为0.65,二阶段模式年龄约为2.9 Ga;二长花岗岩(TA1812)εHf (t) 值为-0.4~2.7,平均值为1.31,二阶段模式年龄为 3 073~2 886 Ma,平均值约为2.9 Ga;二长花岗岩(TA1817)εHf (t) 值为0.3~4.7,平均值为3.35,二阶段模式年龄为3 032~2 762 Ma,平均值约为2.8 Ga。在εHf (t)-t 图解上,鲁西地区新太古代花岗岩和二长花岗岩年龄演化线均落在2.9~2.8 Ga地壳演化线上,且与二阶段模式年龄大致相同,即表明鲁西地区新太古代花岗岩和二长花岗岩源于2.9~2.8 Ga的古老地壳重融。鲁西地区新太古代花岗岩和二长花岗岩均表现为高w(SiO2)、w(Al2O3)和富Na2O特征,大部分属于准铝质岩石。稀土元素球粒陨石标准化分布型式上,均表现为轻稀土元素(LREE)富集和重稀土元素(HREE)亏损,且中重稀土元素出现分馏。花岗岩样品中,有两个样品(TA1801-1与TA1824)表现出Ta富集,其余样品均表现为K、Rb、Ba和Th等大离子亲石元素富集,Nb、Ta、Ti亏损。二长花岗岩也同样表现为K、Rb、Ba和Th等大离子亲石元素富集,Nb、Ta、Ti亏损,部分熔融残余矿物存在石榴石、金红石以及少量斜长石、角闪石。根据上述地球化学特征, 并结合区域地质特征,鲁西地区新太古代花岗岩和二长花岗岩构造背景为同碰撞背景,该构造模式是大陆地壳有效增生。 相似文献
916.
2013年6~7月在广西平果县中铝广西分公司3号排泥库附近出现密集小震群活动。本文搜集本次震群中146次可用于计算尾波的ML1.0地震的近距离台站数字地震波形,利用波形高信噪比的尾波时间域信号,采用计算尾波品质因子Q_C(f)值的Sato模型,通过滤波及去除环境噪声,计算了地震波传播路径上的尾波Q_C(f)值;拟合Q_C(f)值与频率f之间的关系,分析了排泥库区域地震波衰减的时空特征。根据信噪比及计算要求,从近场7个台站的记录中挑选出273条三分向记录,计算尾波衰减参数,得到尾波Q_C(f)与频率f的关系为:Q(f)=(69.07±40.09)f~(0.90±0.23)。结果表明,本区域为低衰减区域,库区Q值相对较高,地震波衰减较慢,且Q值对频率的依赖性不强,研究区介质非均匀性程度低,介质较为稳定。 相似文献
917.
利用安徽省部分强震动台站记录的地脉动数据和历史地震数据,采用H/V谱比法和噪声功率谱密度函数法,对比分析台站的场地响应及背景噪声,结果表明:全椒、马鞍山地震台的场地卓越周期小且背景噪声低;沈巷地震台卓越周期大且背景噪声高;三山地震台无明显卓越周期;地震台站背景噪声与场地响应曲线之间不存在一一对应关系。 相似文献
918.
QuanYou Liu ShengFei Qin Jian Li WenHui Liu DianWei Zhang QingHua Zhou AnPing Hu 《中国科学D辑(英文版)》2008,51(1):174-182
According to gas compositional and carbon isotopic measurement of 114 gas samples from the Kuqa depression, accumulation of the natural gases in the depression is dominated by hydrocarbon gases, with high gas dryness (C1/C1–4) at the middle and northern parts of the depression and low one towards east and west sides and southern part. The carbon isotopes of methane and its homologues are relatively enriched in 13C, and the distributive range of δ 13C1, δ 13C2 and δ 13C3 is ?32‰–?36‰, ?22‰–?24‰ and ?20‰–?22‰, respectively. In general, the carbon isotopes of gaseous alkanes become less negative with the increase of carbon numbers. The δ 13 \(C_{CO_2 } \) value is less than ?10‰ in the Kuqa depression, indicating its organogenic origin. The distributive range of 3He/4He ratio is within n × 10?8 and a decrease in 3He/4He ratio from north to south in the depression is observed. Based on the geochemical parameters of natural gas above, natural gas in the Kuqa depression is of characteristics of coal-type gas origin. The possible reasons for the partial reversal of stable carbon isotopes of gaseous alkanes involve the mixing of gases from one common source rock with different thermal maturity or from two separated source rock intervals of similar kerogen type, multistages accumulation of natural gas under high-temperature and over-pressure conditions, and sufficiency and diffusion of natural gas. 相似文献
919.
Numerous Fe–Cu deposits are hosted in the late Paleoproterozoic Dongchuan and Dahongshan Groups in the Kangdian region, SW
China. The Dongchuan Group is composed of siltstone, slate, and dolostone with minor volcanic rocks, whereas the Dahongshan
Group has undergone lower amphibolite facies metamorphism and consists of quartz mica-schist, albitite, quartzite, marble
and amphibolite with local migmatite. Deposits in the Dongchuan Group are commonly localized in the cores of anticlines, in
fault bends and intersections, and at lithological contacts. Orebodies are closely associated with breccias, which are locally
derived from the host rocks. Fe-oxides (magnetite and/or hematite) and Cu-sulfides (chalcopyrite, bornite) form disseminated,
vein-like and massive ores, and typically fill open spaces in the host rocks. The deposits have extensive albite alteration
and local K-feldspar alteration overprinted by quartz, carbonate, sericite and chlorite. Deposits in the Dahongshan Group
have orebodies sub-parellel to stratification and show crude stratal partitioning of metals. Fe-oxide ores occur as massive
and/or banded replacements within the breccia pipes, whereas Cu-sulfide ores occur predominantly as disseminations and veinlets
within mica schists and massive magnetite ores. Ore textures suggest that Cu-sulfides formed somewhat later than Fe-oxides,
but are possibly within the same mineralization event. Both ore minerals predated regional Neoproterozoic metamorphism. Both
orebodies and host rocks have undergone extensive alteration of albite, scapolite, amphibole, biotite, sericite and chlorite.
Silica and carbonate alterations are also widespread. Ore-hosting strata have a LA-ICP-MS zircon U–Pb age of 1681 ± 13 Ma,
and a dolerite dyke cutting the Fe-oxide orebodies has an age of 1659 ± 16 Ma. Thus, the mineralization age of the Dahongshan
deposit is constrained at between the two. All ores from the two groups have high Fe and low Ti, with variable Cu contents.
Locally they are rich in Mo, Co, V, and REE, but all are poor in Pb and Zn. Sulfides from the Fe–Cu deposits have δ34S values mostly in the range of +2 to +6 per mil, suggesting a mix of several sources due to large-scale leaching of the strata
with the involvement of evaporites. Isotopic dating and field relationships suggest that these deposits formed in the late
Paleoproterozoic. Ore textures, mineralogy and alteration characteristics are typical of IOCG-type deposits and thus define
a major IOCG metallogenic province with significant implications for future exploration. 相似文献
920.
Fluid Inclusions and Hydrogen,Oxygen, and Lead Isotopes of the Antuoling Molybdenum Deposit,Northern Taihang Mountains,China 总被引:1,自引:0,他引:1 下载免费PDF全文
Meng Zhe Jian‐zhong Hu Yang Song Xue‐qin Zhang Hai‐yang Ding Wei Zhou 《Resource Geology》2017,67(4):399-413
The Antuoling Mo deposit is a major porphyry‐type deposit in the polymetallic metallogenic belt of the northern Taihang Mountains, China. The processes of mineralization in this deposit can be divided into three stages: an early quartz–pyrite stage, a middle quartz–polymetallic sulfide stage, and a late quartz–carbonate stage. Four types of primary fluid inclusions are found in the deposit: two‐phase aqueous inclusions, daughter‐mineral‐bearing multiphase inclusions, CO2–H2O inclusions, and pure CO2 inclusions. From the early to the late ore‐forming stages, the homogenization temperatures of the fluid inclusions are 300 to >500°C, 270–425°C, and 195–330°C, respectively, with salinities of up to 50.2 wt%, 5.3–47.3 wt%, and 2.2–10.4 wt% NaCl equivalent, revealing that the ore‐forming fluids changed from high temperature and high salinity to lower temperature and lower salinity. Moreover, based on the laser Raman spectra, the compositions of the fluid inclusions evolved from the NaCl–CO2–H2O to the NaCl–H2O system. The δ18OH2O and δD values of quartz in the deposit range from +3.9‰ to +7.0‰ and ?117.5‰ to ?134.2‰, respectively, reflecting the δD of local meteoric water after oxygen isotopic exchange with host rocks. The Pb isotope values of the sulfides (208Pb/204Pb, 36.320–37.428; 207Pb/204Pb, 15.210–15.495; 206Pb/204Pb, 16.366–17.822) indicate that the ore‐forming materials originated from a mixed upper mantle–lower crust source. 相似文献