Program News Bright Prospects for a Significant Improvement of the Earth's Gravity Field Knowledge     

Reiner Rummel 《Marine Geodesy》2013,36(3):219-220

Concern over the impact of change in sea level is of topical interest internationally, but for the small island states of the Caribbean, a significant increase would prove to be catastrophic. The potential problem is being addressed as part of the much larger issue of climate change, and just this year a regional Climate Change Centre was established in Belize. Means of adapting to accommodate change will be considered under the Mainstream Adaptation to Climate Change (MACC) project, but initially the threat needs to be quantified. While meteorological offices have been accumulating weather data in some parts of the region for many years, sea level data is more scarce. This work puts least squares methods to test by applying them to spectral analysis of intermittent data sets acquired over periods of 6 and 9 years at two locations in Trinidad. The resulting sea level models that include 13 periodic components, datum bias, trend and atmospheric pressure are validated using fundamental historical information and observations that form the subject of discussion among local professional surveyors. Results show that while sea level at a location in North Trinidad is rising at the rate of about 1 mm a year, the change at a Southern site is about four times this amount. Horizontal movement has been measured across a tectonic fault that parts the island, and it is now apparent that there may be some vertical motion on this or some other fault lines in the region.  相似文献   

A mesocosm experiment investigating the effects of substratum quality and wave exposure on the survival of fish eggs     

Stefan Stoll  Wolfgang Nikolaus Probst  Reiner Eckmann  Philipp Fischer 《Aquatic Sciences - Research Across Boundaries》2010,72(4):509-517

In a mesocosm experiment, the attachment of bream (Abramis brama) eggs to spawning substrata with and without periphytic biofilm coverage and their subsequent survival with and without low-intensity wave exposure were investigated. Egg attachment was reduced by 73% on spawning substrata with a natural periphytic biofilm, compared to clean substrata. Overall, this initial difference in egg numbers persisted until hatching. The difference in egg numbers was even increased in the wave treatment, while it was reduced in the no-wave control treatment. Exposure to a low-intensity wave regime affected egg development between the two biofilm treatments differently. Waves enhanced egg survival on substrata without a biofilm but reduced the survival of eggs on substrata with biofilm coverage. In the treatment combining biofilm-covered substrata and waves, no attached eggs survived until hatching. In all treatments, more than 75% of the eggs became detached from the spawning substrata during the egg incubation period, and <1% of these detached eggs survived within the substratum interstices. Hence, detached eggs contributed little to the reproductive success we observed. The implications of these results on the spawning success of fish species that use freshly inundated spawning substrata in shallow waters are discussed.  相似文献   

Fluid influence on mineral reactions in ultrahigh-pressure granulites: a case study in the Śnieżnik Mts. (West Sudetes, Poland)     

Reiner Klemd  Michael Bröcker 《Contributions to Mineralogy and Petrology》1999,136(4):358-373

Small tectonic slices of undeformed eclogites and ultrahigh-pressure granulites occur in three tectonic units of the Śnieżnik Mts. (SW Poland). Ultrahigh-pressure granulite/eclogite transitions with peak metamorphic conditions between 21 and 28 kbar at 800 to 1000 °C occur only in the Złote unit. Conventional U-Pb multigrain analyses of zircons from a mafic granulite provided ²⁰⁷Pb/²⁰⁶Pb ages between 360 to 369 Ma which are interpreted to approximate timing of original crystallisation from a melt. Diffusion kinetics and the restricted availability of a fluid phase mainly controlled the conversion from granulite to eclogite, although some bulk-chemical differences were also recognised. The ultrahigh-pressure granulites from the Złote unit exclusively contain H₂O-rich inclusions with variable salinities which distinguishes them from high-temperature (HT)-granulites world-wide. This is also in contrast to the fluid regime (H₂O-N₂-CO₂) recognised in the lower-temperature eclogites (600–800 °C) from the closely associated Międzygórze and Śnieżnik units. The variation in fluid composition between the lower-temperature eclogites and ultrahigh-pressure granulites on the one hand and ultrahigh-pressure granulites and HT-granulites on the other hand probably indicates contrasting P-T-t paths as a result of different tectonic environments. Received: 15 June 1998 / Accepted: 2 March 1999  相似文献   

High-pressure relics in meta-sediments intercalated with the Weissenstein eclogite,Münchberg gneiss complex,Bavaria     

Reiner Klemd  Siegfried Matthes  Martin Okrusch 《Contributions to Mineralogy and Petrology》1991,107(3):328-342

The mineral assemblages in the eclogites and meta-sediments of the Münchberg gneiss complex suggest minimum pressures of about 15 kbar, and temperatures of 600±30° C for the eclogite-facies metamorphism. Both rock types underwent a subsequent amphibolite-facies metamorphism at almost the same temperature range. In the Weissenstein borehole the eclogites and meta-sediments show an intimate interlayering on a centimetre scale. Contacts between the two rock types are often sharp and untectonized suggesting in-situ metamorphism of the eclogites. The following features indicate that the gneisses were subjected to eclogite-facies metamorphism:

1. Phengite relics and phengite inclusions in garnet contain up to 3.45 Si per formula unit while amphibolite facies phengites have considerably lower Si-contents (3.0–3.25 p.f.u.).
2. Omphacite relics occur in the form of Na-augite (6–9 mol% jadeite)-oligoclase symplectites.
3. Garnets with up to 40 mol% of the pyrope component occur.

The geological and mineral-chemical data indicate that large volumes of crustal material have been buried to depths possibly exceeding 70 km. The preservation of primary eclogitic textures as well as symplectitic textures in the presence of a fluid phase, are indicative of a rapid decompression. This would suggest a tectonic uplift (e.g. underthrusting) as is also indicated by the virtually constant temperature range during the uplift.  相似文献   

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   

La restitution géométrique des profils sismiques continus     

Jean Goguel 《Marine Geology》1971

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Influence of tropical Pacific SST on seasonal precipitation in Colombia: prediction using El Niño and El Niño Modoki     

Samir Córdoba-Machado  Reiner Palomino-Lemus  Sonia Raquel Gámiz-Fortis  Yolanda Castro-Díez  María Jesús Esteban-Parra 《Climate Dynamics》2015,44(5-6):1293-1310

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Multiple sources for mineralizing fluids in the Charmitan gold(-tungsten) mineralization (Uzbekistan)   总被引：1，自引：0，他引：1  

Torsten Graupner  Samuel Niedermann  Dieter Rhede  Ulf Kempe  Reimar Seltmann  C. Terry Williams  Reiner Klemd 《Mineralium Deposita》2010,45(7):667-682

Mineral assemblages present within the Charmitan gold(-tungsten) quartz-vein mineralization have been investigated for their cathodoluminescence behaviour, chemical composition and noble gas isotope systematics. This inventory of methods allows for the first time a systematic reconstruction of the paragenetic relationships of quartz, scheelite, sulphides and native gold within the gold mineralization at Charmitan and provides the basis to utilise noble gas data in the discussion of sources and evolution of ore-forming fluids. The vein quartz is classified into four generations based on microscopic and cathodoluminescence investigations. Quartz I shows intense brittle deformation as associated scheelite I. Undeformed scheelite II overgrows scheelite I and has lower light rare earth element and higher intermediate rare earth element contents as well as higher strontium concentrations. Scheelite II is associated with the economic gold mineralization and formed during re-crystallisation and re-precipitation of material which was partly re-mobilised from early scheelite I during infiltration of gold-bearing fluids. Early stage native gold inclusions are often associated with stage 2 sulphides, scheelite II and bismuth tellurides and contain Ag (3.6–24.4 wt.%), Hg (≤1.0 wt.%) and Bi (≤0.2 wt.%). Later stage electrum grains occur in association with stage 3 sulphides and sulphosalts and contain Hg (<0.8 wt.%) and elevated Sb concentrations (up to 3.0 wt.%). Noble gas isotope data (³He/⁴He: 0.2-0.4 Ra) for hydrothermal ore fluids trapped in the gold-related sulphides and sulphosalts (stage 2 pyrite and arsenopyrite; stage 3 pyrite, sphalerite, galena and lead sulphosalts) suggest that diverse fluid sources were involved in the formation of the Charmitan gold deposit. These data are indicative of a small, but significant input of fluids from external, deep-seated (mantle and possibly lower crust) sources. A decrease in the input of mantle helium and an increasing role of crustal helium from early to later stages of the mineralization is suggested by the measured ³He/⁴He and ⁴⁰Ar*/⁴He ratios. Sulphides from ore veins in meta-sedimentary rocks contain higher portions of meteoric fluids than those in intrusive rock types as indicated by their lower ³He/³⁶Ar ratios. The ³He/³⁶Ar ratios in the meta-sedimentary rocks agree well with ratios typical of gold mineralizations in the Tien Shan gold province completely hosted by meta-sedimentary sequences, indicating intense fluid-wall rock interaction.  相似文献