Late Mesozoic crust-mantle interaction and lower crust components in South China: A geochemical study of mafic granulite xenoliths from Cenozoic basalts   总被引：4，自引：1，他引：3  

于津海  徐夕生  周新民 《中国科学D辑(英文版)》2003,46(5):447-460

Mafic granulite xenoliths have been discovered in many volcanoes (especially alkali basalt and kimberlite) all over the world. They formed generally in lower crust, and recorded lots of in- formation on the lithosphere formation and crust-mantle interacti…  相似文献   

Sea surface height and transport stream function of the South China Sea from a variable-grid global ocean circulation model   总被引：8，自引：0，他引：8  

魏泽勋  方国洪  崔秉昊  方越  何宜军 《中国科学D辑(英文版)》2003,46(2):139-148

The study on the South China Sea (SCS) circulation has a history of more than 40 years. Nevertheless, the SCS circulation is not fully understood compared with the Bohai Sea, Yellow Sea and East China Sea (ECS). Many numerical studies on the SCS circulati…  相似文献   

Geology and isotopic composition of helium,neon, xenon and metallogenic age of the Jinding and Baiyangping ore deposits,northwest Yunnan,China   总被引：23，自引：0，他引：23  

薛春纪  陈毓川  王登红  杨建民  杨伟光  曾荣 《中国科学D辑(英文版)》2003,46(8):789-800

TheJindingoredeposit,locatedinthenorthwestYunnanProvince,isthelargestPb-Zndeposit(Pb Zn>15Mt1),averagingZn=6.08%andPb/Zn=1/4.7)inChinaatpresent.Toitsnorth,alargeCu-Co-AgdeposithasbeenfoundatBaiyangpingrecently1).TheJindingPb-Zndepositishostedinsandstonesa…  相似文献   

The carbon isotope composition of C<Superscript>3</Superscript> herbaceous plants in loess area of northern China     

Guoan?WangEmail author  Jiamao?Han  Dongsheng?Liu 《中国科学D辑(英文版)》2003,46(10):1069-1076

¹³C of 367 C₃ herbaceous plants was measured in loess area in northern China. Their δ¹³C values vary between −21.7%. and −30.0%., with a mean of −26.7%.. In the center of Loess Plateau (semimoist area) with annual precipitation of 400–600 mm, the δ¹³ C values of C₃ herbaceous plants range from −24.4%. to −28.5%., with a mean of −27.5%.. In the west of Loess Plateau (semiarid and arid area) with annual precipitation less than 400 mm, they range between −21.7%. and −30.0%., with a mean of −26.2%.. Annual precipitation is the main factor that makes δ¹³C values of C₃ herbaceous plants in the west greater than those in the central Loess Plateau. The composition of δ¹³C in C₃ plants increases with deceasing annual precipitation, and the mean change is −49%./100 mm.  相似文献   

Sea-level changes and hydrothermal sedimentary mineralization of large-superlarge ore deposits among Sinian to Triassic in South China     

Chen?DuofuEmail author  Chen?Xianpei  Chen?Guangqian 《中国科学D辑(英文版)》2003,46(1):154-163

Among the Sinian to Triassic strata in South China, the stratiform, quasi-stratiform and lenticular metallic deposits in association with hydrothermal sedimentation mainly occur in the four periods: (1) the Sinian Datangpo interglacial period, (2) the early period of Early Cambrian, (3) the late period of Middle Devonian to early period of Late Devonian, and (4) the late period of Early Permian. The four mineralization periods all happened around the maximum flooding period in the third-order seal-level cycle during the ascending stage in the first-order sea-level cycle. The deep seawater layer, starved and non-compensatory basin, low sedimentary rate, and low energy and anoxic environment during the maximum flooding period are very suitable for the formation and preservation of large to superlarge hydrothermal sedimentary deposits. The maximum flooding period also coincided with the intensified regional tectonism, extensive deep magmatism and hydrothermal sedimentation, which provide, for the formation of large to superlarge hydrothermal sedimentary deposits through the rapid accumulation of hydrothermal sediments, the needed dynamics, ore-forming materials and favorable passway for hydrothermal fluids to enter the basin.  相似文献   

Photochemical degradation of organic iron complexing ligands in seawater     

Rodney?T.?PowellEmail author  Amy?Wilson-Finelli 《Aquatic Sciences - Research Across Boundaries》2003,65(4):367-374

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Geodynamic settings of Mesozoic large-scale mineralization in North China and adjacent areas   总被引：11，自引：0，他引：11  

Jingwen?MaoEmail author  Yitian?Wang  Zuoheng?Zhang  Jinjie?Yu  Baogui?Niu 《中国科学D辑(英文版)》2003,46(8):838-851

Based on the summary of the highly precise datings of the metal deposits and related granitic rocks in North China craton and adjacent areas, such as the molybdenite Re-Os datings,⁴⁰Ar-³⁹Ar datings of mica, K-feldspar and quartz, some Rb-Sr isochrons, and the SHRIMP zircon U-Pb dating and single grain zircon U-Pb dating, we suggest that the large-scale mineralization in North China craton and adjacent areas take place in three periods of 200-160Ma, 140Ma±, and 130-110Ma. Their corresponding geodynamic settings are proposed to be the collision orogenic process, transformation of the tectonic regime, and delamination of the lithosphere, respectively, in light of analyzing the Mesozoic geodynamic evolution in the North China craton.  相似文献   

Photodegradation of pharmaceuticals in the aquatic environment: A review   总被引：6，自引：0，他引：6  

Anne?L.?Boreen  William?A.?ArnoldEmail author  Kristopher?McNeillEmail author 《Aquatic Sciences - Research Across Boundaries》2003,65(4):320-341

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Endogenous hydrophobic compounds affect the hydrophobic capacity of plants and influence the forest filter effect     

H.?KylinEmail author  A.?Hellstr?m 《Stochastic Environmental Research and Risk Assessment (SERRA)》2003,17(4):249-251

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Revising the paradigm of tidal analysis – the uses of non-stationary data     

David A.?JayEmail author  Tobias?Kukulka 《Ocean Dynamics》2003,53(3):110-125

Surface elevation and current records contain non-tidal variance, often dismissed as noise. The processes responsible for the non-tidal component may also modulate the tidal signal, altering its strength and frequency structure. Because of their manner of generation and propagation, internal tides are inherently irregular. The non-stationary character of these and other tidal processes provides an integral and useful property of tidal records, because it provides an opportunity to obtain insights into tidal dynamics and the interaction of tidal and non-tidal processes. It is, moreover, productive to use multiple approaches in analyzing coastal and estuarine tidal processes so that both the time-varying and average frequency content are determined. Only by confronting the causes of non-stationary behaviour in this way can some of the remaining challenges in tidal analysis and prediction be overcome, e.g. shelf and estuarine currents, river tides, internal tides, tide-surge interactions and tidally influenced ecological processes. Several examples illustrate the utility of non-stationary tidal analysis methods.Responsible Editor: Jens Kappenberg  相似文献