俯冲洋岛玄武岩脱水释放的水流体成分：来自西天山榴辉岩相高压脉的约束     

熊贤明  高俊  Reiner KLEMD  黄德志 《岩石学报》2006,22(1):103-114

俯冲洋壳的脱水作用对于岛弧火山岩的成因具有重要意义。西天山高压低温变质带中切割主岩蓝片岩/榴辉岩的榴辉岩相脉体记录了古生代俯冲带中的脱水过程。脉体具有典型高压矿物组合：石榴石(＞8%)+绿辉石(15%)+石英(＞55%)+蓝闪石(5%)+冻蓝闪石(10%)±黝帘石±方解石。高压脉及其主岩的岩相学与矿物化学研究表明流体是在俯冲过程中蓝片岩向榴辉岩进变质条件下释放。脉的主量元素成分显示流体富Si。主岩的稀土元素和微量元素表明其原岩为洋岛玄武岩(OIB)。脉和主岩具有相似的微量元素配分模式,并且相对N-MORB都显示富Li、Be、Cs、Rb、Ba、Pb、La的特点。通过模拟计算,在高压脉、与脉平衡的流体以及模拟的原生流体中都富集流体活动性元素(Li、Be、Pb)和LILE(Cs、Rb、Ba),贫HFSE(Nb)和REE(Nd、Sm)。证实了在古生代南天山洋俯冲时洋岛玄武岩脱水释放出富Li、Be、LILE、La和Pb,贫HFSE和HREE的流体。  相似文献   

Different carbon reservoirs of auriferous fluids in African Archean and Proterozoic gold deposits? Constraints from stable carbon isotopic compositions of quartz-hosted CO2-rich fluid inclusions     

Volker Lüders  Reiner Klemd  Thomas Oberthür  Birgit Plessen 《Mineralium Deposita》2015,50(4):449-454

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Ein theoretisches Modell für den Jahresgang der meridionalen Ozonverteilung in der Stratosphäre     

Dr. Reiner Gebhart 《Meteorology and Atmospheric Physics》1971,20(3):247-276

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Tectonic evolution and metallogeny of the Chinese Altay and Tianshan by J. Mao,R.J. Goldfarb,R. Seltmann,D. Wang,W. Xiao,C. Hart (eds)     

Reiner?KlemdEmail author 《Mineralium Deposita》2004,39(4):521-522

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Oxygen Utilization and Organic Carbon Remineralization in the Upper Water Column of the Pacific Ocean     

Richard A. Feely  Christopher L. Sabine  Reiner Schlitzer  John L. Bullister  Sabine Mecking  Dana Greeley 《Journal of Oceanography》2004,60(1):45-52

As a part of the JGOFS synthesis and modeling project, researchers have been working to synthesize the WOCE/JGOFS/DOE/NOAA global CO₂ survey data to better understand carbon cycling processes in the oceans. Working with international investigators we have compiled a Pacific Ocean data set with over 35,000 unique samples analyzed for at least two carbon species, oxygen, nutrients, chlorofluorocarbon (CFC) tracers, and hydrographic parameters. We use these data here to estimate in-situ oxygen utilization rates (OUR) and organic carbon remineralization rates within the upper water column of the Pacific Ocean. OURs are derived from the observed apparent oxygen utilization (AOU) and the water age estimates based on CFCs in the upper water and natural radiocarbon in deep waters. The rates are generally highest just below the euphotic zone and decrease with depth to values that are much lower and nearly constant in water deeper than 1200 m. OURs ranged from about 0.02–10 μmol kg⁻¹yr⁻¹ in the upper water masses from about 100–1000 m, and averaged = 0.10 μmol kg⁻¹yr⁻¹ in deep waters below 1200 m. The OUR data can be used to directly estimate organic carbon remineralization rates using the C:O Redfield ratio given in Anderson and Sarmiento (1994). When these rates are integrated we obtain an estimate of 5.3 ± 1 Pg C yr⁻¹ for the remineralization of organic carbon in the upper water column of the Pacific Ocean. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Total particulate and organic fluxes in anoxic Framvaren waters     

Kristoffer Ns  Jens M. Skei  Paul Wassmann 《Marine Chemistry》1988,23(3-4)

Cylindrical sediment traps were deployed at various depths in the anoxic water of Framvaren for two periods of one year (1981–1982 and 1983–1984). The traps were emptied three times during 1981–1982 and five times during 1983–1984. The vertical fluxes of total suspended material, organic carbon and nitrogen were calculated on a daily and annual basis. The average annual sediment flux 20 m above the bottom was approximately 60 g m⁻² y⁻¹ and the flux of organic carbon was 20 g m⁻² y⁻¹. On the basis of an average C/N ratio of 8 and a constant carbon flux below a depth of 20 m, it is concluded that little mineralization of the organic matter takes place in the anoxic water column. Assuming a primary production of the order to 50–100 g m⁻² y⁻¹, 22–24% of that reaches the anoxic water masses. Further breakdown of organic matter takes place in the surface sediments.  相似文献   

俯冲带流体——来自（超）高压变质岩石的证据     

高俊  李继磊  马智佩  Reiner KLEMD 《地质学报》2024,98(3):758-782

俯冲带是地球上岩浆活动、高压—超高压变质作用、中深源地震、壳幔物质交换、元素循环和铜金大规模成矿的集中发生场所。富水流体不仅调控了这些地质作用,而且也深刻影响了全球C、S等挥发分的循环。当蚀变大洋岩石圈及上覆沉积物进入俯冲带中深部（15~300 km）,伴随由葡萄石- 绿纤石相至超高压榴辉岩相的递进变质作用,含水矿物在不同深度的分解造成流体释放为一连续过程。除极端高地温梯度环境之外,大多数俯冲带洋壳释放的流体为富水流体。但,俯冲带不同深度所产生的流体特征有明显差异。出露于全球造山带的高压—超高压变质地体保存了分凝体、脉体、水压致裂角砾岩等流体作用的有力证据,绿辉石、石榴子石、绿帘石等矿物中原生流体包裹体为流体的直接记录。在俯冲带中等深度（＜65 km）,流体是溶质含量很低的含卤化物水溶液,可含CO2-3、SO2-4、HS-等组分,其所含Si、Al、Ca、Mg、Fe、Na主量元素溶质相当于海水中固化物量的2~3倍,并具大离子亲石元素（LILE）、轻元素（B、Li）富集和高场强元素（HFSE）亏损的特点。当深度≥65 km时,流体转化为类似于超临界性质的溶液,含CH4、C2H6、H2S等挥发分,其所含主量元素溶质显著增加,微量元素除LILE等外,还负载相当量的HFSE和过渡族成矿元素。俯冲带65~100 km深度,为富水流体向超临界流体转变的区间。这种流体具有“亚超临界”性质,发生了氧化还原性质和元素溶解能力的渐变,并伴随硬柱石和角闪石的最终耗尽。高压变质岩石及相关脉体的O、Sr、Nd和金属同位素示踪研究表明俯冲带流体的源区多样,有蚀变基性洋壳、地幔橄榄岩和沉积物,并保存了海底热液蚀变作用的印迹。流体以脉冲方式沿网络状裂隙呈隧道式运移和传输,规模可达千米级,时间尺度在数月至数百年。目前通过高压—超高压变质岩的研究对俯冲带流体已经有了深入的了解,但展望未来,该领域依然有诸多争议和科学问题值得探索。  相似文献   

Seasonal and interannual variations in satellite derived sea surface temperature of the Baltic Sea in the 1990s     

Herbert Siegel  Monika Gerth  Reiner Tiesel  Gisela Tschersich 《Ocean Dynamics》1999,51(4):407-422

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Nb–Ta fractionation by partial melting at the titanite–rutile transition     

Timm John  Reiner Klemd  Stephan Klemme  Jörg A. Pfänder  J. Elis Hoffmann  Jun Gao 《Contributions to Mineralogy and Petrology》2011,161(1):35-45

During the evolution of the Earth, distinct geochemical reservoirs with different Nb/Ta ratios have developed. Archean granitoids of the tonalite–trondhjemite–granodiorite (TTG) suite, which represent the Earth’s early continental crust, show larger Nb/Ta variations than any other Earth reservoir. This implies that significant Nb–Ta fractionation must have occurred during early crust formation, while the underlying mechanism behind is still unclear. Here, we present a new model on how Nb may be fractionated from Ta during partial melting of subducted oceanic crust. Our data show that Nb/Ta ratios in melts derived from rutile- and titanite-bearing eclogite are largely controlled by the modal relative abundances of rutile and titanite in the source. High modal ratios of titanite over rutile generate melts with very high Nb/Ta (>60), whereas low modal titanite/rutile produces melts with much lower Nb/Ta (≤30). Very low Nb/Ta (<16) occur when all Ti-phases are consumed at very high degrees of melting. As the modal ratio of titanite to rutile is a function of pressure, the Nb/Ta of melts is a function of melting depth. Our new model helps to explain the extreme variation of Nb/Ta observed in many TTGs and thus how Nb and Ta were fractionated during the early evolution of the Earth. Furthermore, the model also indicates that simple one-stage melting models for mafic crust are not sufficient to explain the formation of TTGs.  相似文献   

GOCE gravitational gradiometry   总被引：16，自引：6，他引：10  

Reiner Rummel  Weiyong Yi  Claudia Stummer 《Journal of Geodesy》2011,85(11):777-790

GOCE is the first gravitational gradiometry satellite mission. Gravitational gradiometry is the measurement of the second derivatives of the gravitational potential. The nine derivatives form a 3 × 3 matrix, which in geodesy is referred to as Marussi tensor. From the basic properties of the gravitational field, it follows that the matrix is symmetric and trace free. The latter property corresponds to Laplace equation, which gives the theoretical foundation of its representation in terms of spherical harmonic or Fourier series. At the same time, it provides the most powerful quality check of the actual measured gradients. GOCE gradiometry is based on the principle of differential accelerometry. As the satellite carries out a rotational motion in space, the accelerometer differences contain angular effects that must be removed. The GOCE gradiometer provides the components V _xx , V _yy , V _zz and V _xz with high precision, while the components V _xy and V _yz are of low precision, all expressed in the gradiometer reference frame. The best performance is achieved inside the measurement band from 5 × 10^–3 to 0.1 Hz. At lower frequencies, the noise increases with 1/f and is superimposed by cyclic distortions, which are modulated from the orbit and attitude motion into the gradient measurements. Global maps with the individual components show typical patterns related to topographic and tectonic features. The maps are separated into those for ascending and those for descending tracks as the components are expressed in the instrument frame. All results are derived from the measurements of the period from November to December 2009. While the components V _xx and V _yy reach a noise level of about \({10\;\rm{\frac{mE}{\sqrt{Hz}}}}\), that of V _zz and V _xz is about \({20\; \rm{\frac{mE}{\sqrt{Hz}}}}\). The cause of the latter’s higher noise is not yet understood. This is also the reason why the deviation from the Laplace condition is at the \({20 \;\rm{\frac{mE}{\sqrt{Hz}}}}\) level instead of the originally planned \({11\;\rm{\frac{mE}{\sqrt{Hz}}}}\). Each additional measurement cycle will improve the accuracy and to a smaller extent also the resolution of the spherical harmonic coefficients derived from the measured gradients.  相似文献