The baryte-bearing beryl-phosphate pegmatite Plössberg—A missing link between pegmatitic and vein-type barium mineralization in NE Bavaria, Germany     

Harald G. Dill  Berthold Weber  Reiner Botz 《Chemie der Erde / Geochemistry》2011,71(4):377-387

Pegmatites and aplites enriched in P, Be, Nb, Ta and Li occur in the high-temperature metamorphic lithological units of the NE Bavarian Basement, SE Germany. They are accompanied by Ba mineralization, in vein-type deposits in the basement as well as in its foreland. Locally, Ba minerals are encountered in the late Variscan pegmatites and aplites too. The shallow discordant stock-like pegmatites (Hagendorf-type) are barren as to Ba, but in the tabular, concordant aplites and pegmatites Ba was concentrated (Plössberg-type). These concordant pegmatites and aplites are supposed to be the root zone of the intrusive pegmatites. In the rare case of low sulfur fugacity, Ba forms Ba–Zr–K–Sc phosphates/silicates in the pegmatites (transition of magmatic into the hydrothermal stages I/II). Under high sulfur fugacity, Ba is accommodated within the same stages in the structure of baryte. Barium is not accommodated in the lattice of phosphates during or in the immediate aftermaths of the emplacement of these Be–P–Nb–Ta pegmatites (stage III). This element shows up again in APS minerals during supergene alteration under acidic conditions (stage IV). Considering the host rocks of baryte mineralization, the Sr contents of baryte increased from the early Paleozoic to the Late Triassic. The Sr contents of baryte are a function of the depth below ground in the vein-type deposits and in the shear-zones bounding the tabular concordant pegmatites. Beryl is not only a marker mineral for the shear-zone-hosted pegmatites but can also be used as a tool for the geodynamic positioning of these pegmatites using its oxygen isotopes. A subdivision of the pegmatites into intrusive and shear-zone hosted may be achieved by its REE and minor elements.  相似文献   

Challenging the planetary boundaries II: Assessing the sustainable global population and phosphate supply,using a systems dynamics assessment model     

Harald U. Sverdrup  Kristin Vala Ragnarsdottir 《Applied Geochemistry》2011

A systems dynamics model was developed to assess the planetary boundary for P supply in relation to use by human society. It is concluded that present day use rates and poor recycling rates of P are unsustainable at timescales beyond 100+ a. The predictions made suggest that P will become a scarce and expensive material in the future. The study shows clearly that market mechanisms alone will not be able to secure an efficient use before a large part of the resource will have been allowed to dissipate into the natural environment. It is suggested that population size management and effective recycling measures must be planned long term to avoid unpleasant consequences of hunger and necessary corrections imposed on society by mass balance and thermodynamics.  相似文献   

Divergent growth trajectories in China’s chemical industry: the case of the newly developed industrial parks in Shanghai,Nanjing and Ningbo   总被引：1，自引：0，他引：1  

Zeng  Gang  Bathelt  Harald 《GeoJournal》2011,76(6):675-698

In the late 1990’s, the “new-economy” industries in China proved to be relatively vulnerable and were strongly hit by the financial crisis in Asia. As a result, a new economic support policy was introduced in China’s Yangtze Delta region, which put greater emphasis on the support of traditional industrial sectors, including the chemical industry. This paper investigates the effects of the growth of this industry, as well as the potential and current problems emerging from new growth paths. It compares the growth of three newly developed chemical industry parks in Shanghai, Nanjing and Ningbo. The paper is based on an institutional perspective of clustering processes arguing that regional industrialization is subject to formal and informal institutions which shape the growth paths and contribute to divergent regional trajectories. Although these industrial parks all benefit from the general economic upswing in China, their development is influenced by different business models, economic contexts, goals and strategies, leaving room for divergence and specialization. Due to the existing structure of operations, these parks have a great deal of potential but also face substantial challenges, such as the establishment of internal networks and close customer linkages. It is argued that this might limit their innovative capability in the future. Furthermore, their growth prospects differ depending on future government policies.  相似文献   

Environmental impact of ancient small-scale mercury ore processing at Pšenk on soil (Idrija area, Slovenia)     

Tamara Terši?Mateja Gosar  Harald Biester 《Applied Geochemistry》2011,26(11):1867-1876

The Idrija mine was the second largest Hg mine in the world surpassed only by the Almaden mine in Spain. It has been estimated that almost 145,000 tons of Hg was produced during operation (1490-1995) of the mine. In the first decade of Hg mining in Idrija the ore was roasted in piles; after that it was roasted for 150 years, until 1652, in earthen vessels at various sites in the woods around Idrija. Pšenk is one out of 21 localities of ancient roasting sites established on the hills surrounding Idrija and one of the largest localities of roasting vessel fragments. The unique way of roasting very rich Hg ore at this site has resulted in soil contamination and considerable amounts of waste material that potentially leach Hg into the surrounding environment. The main aim of this study was to determine the distribution and the forms of Hg in contaminated soils in order to evaluate potential environmental risk. Detailed soil sampling was performed on 37,800 m² area to establish the extent of Hg pollution and to investigate Hg transformations and transport characteristics through the 400 a-long period. A total of 156 soil (0-15 cm and 15-30 cm) and SOM (soil organic matter) samples were collected from 73 sampling points. Three soil profiles were sampled to determine vertical distribution of Hg. The main Hg phases were determined by the Hg-thermo-desorption technique. The measured Hg contents in soil samples in the study area vary from 5.5 to almost 9000 mg/kg with a median of 200 mg/kg. In SOM, Hg contents range from 1.4 to 4200 mg/kg with a median of 20 mg/kg. Extremely high Hg contents were found in soil profiles where the metal reaches 37,020 mg/kg. In general, Hg concentrations in all three profiles show a gradual decrease with depth with the minimum values between 140 mg/kg and 1080 mg/kg. The Hg-thermo-desorption curves indicate the presence of Hg in the form of cinnabar and that of Hg bound to organic or mineral soil matter. The distribution of Hg species in soil and SOM samples show almost equal distribution of cinnabar and non-cinnabar Hg compounds. The non-cinnabar fraction shows a little increase with depth, but cinnabar represents a high portion of total Hg (about 40%). Large amounts of potentially mobile and transformable non-cinnabar Hg compounds exist at the roasting site, which are potentially bioavailable.  相似文献   

How Much Physiology is Needed in Forest Gap Models for Simulating Long-Term Vegetation Response to Global Change?     

Harald Bugmann  James F. Reynolds  Louis F. Pitelka 《Climatic change》2001,51(3-4):249-250

  相似文献   

Improving the modeling of the atmospheric delay in the data analysis of the Intensive VLBI sessions and the impact on the UT1 estimates     

Tobias Nilsson  Benedikt Soja  Kyriakos Balidakis  Maria Karbon  Robert Heinkelmann  Zhiguo Deng  Harald Schuh 《Journal of Geodesy》2017,91(7):857-866

The very long baseline interferometry (VLBI) Intensive sessions are typically 1-h and single-baseline VLBI sessions, specifically designed to yield low-latency estimates of UT1-UTC. In this work, we investigate what accuracy is obtained from these sessions and how it can be improved. In particular, we study the modeling of the troposphere in the data analysis. The impact of including external information on the zenith wet delays (ZWD) and tropospheric gradients from GPS or numerical weather prediction models is studied. Additionally, we test estimating tropospheric gradients in the data analysis, which is normally not done. To evaluate the results, we compared the UT1-UTC values from the Intensives to those from simultaneous 24-h VLBI session. Furthermore, we calculated length of day (LOD) estimates using the UT1-UTC values from consecutive Intensives and compared these to the LOD estimated by GPS. We find that there is not much benefit in using external ZWD; however, including external information on the gradients improves the agreement with the reference data. If gradients are estimated in the data analysis, and appropriate constraints are applied, the WRMS difference w.r.t. UT1-UTC from 24-h sessions is reduced by 5% and the WRMS difference w.r.t. the LOD from GPS by up to 12%. The best agreement between Intensives and the reference time series is obtained when using both external gradients from GPS and additionally estimating gradients in the data analysis.  相似文献   

Improving BeiDou precise orbit determination using observations of onboard MEO satellite receivers   总被引：1，自引：0，他引：1  

Haibo Ge  Bofeng Li  Maorong Ge  Yunzhong Shen  Harald Schuh 《Journal of Geodesy》2017,91(12):1447-1460

In recent years, the precise orbit determination (POD) of the regional Chinese BeiDou Navigation Satellite System (BDS) has been a hot spot because of its special constellation consisting of five geostationary earth orbit (GEO) satellites and five inclined geosynchronous satellite orbit (IGSO) satellites besides four medium earth orbit (MEO) satellites since the end of 2012. GEO and IGSO satellites play an important role in regional BDS applications. However, this brings a great challenge to the POD, especially for the GEO satellites due to their geostationary orbiting. Though a number of studies have been carried out to improve the POD performance of GEO satellites, the result is still much worse than that of IGSO and MEO, particularly in the along-track direction. The major reason is that the geostationary characteristic of a GEO satellite results in a bad geometry with respect to the ground tracking network. In order to improve the tracking geometry of the GEO satellites, a possible strategy is to mount global navigation satellite system (GNSS) receivers on MEO satellites to collect the signals from GEO/IGSO GNSS satellites so as that these observations can be used to improve GEO/IGSO POD. We extended our POD software package to simulate all the related observations and to assimilate the MEO-onboard GNSS observations in orbit determination. Based on GPS and BDS constellations, simulated studies are undertaken for various tracking scenarios. The impact of the onboard GNSS observations is investigated carefully and presented in detail. The results show that MEO-onboard observations can significantly improve the orbit precision of GEO satellites from metres to decimetres, especially in the along-track direction. The POD results of IGSO satellites also benefit from the MEO-onboard data and the precision can be improved by more than 50% in 3D direction.  相似文献   

Technical paper: FluMo—a mobile fluid–chemical monitoring unit for geothermal plants     

Harald Milsch  Ronny Giese  Mathias Poser  Stefan Kranz  Elvira Feldbusch  Simona Regenspurg 《Environmental Earth Sciences》2013,70(8):3459-3463

A versatile fluid–chemical monitoring unit has been developed in the framework of the geothermal research platform Groß Schönebeck, Germany. It enables selective online and in situ measurements of various physico-chemical parameters at different surface locations of a geothermal fluid loop. Sensors are provided for pressure, temperature, volumetric flow rate, density, pH-value, redox potential, oxygen content, and electrical conductivity. In addition, the apparatus features two fluid samplers to manually collect fluid under in situ conditions and ultimately analyze the solution composition. All devices are mounted on a rack allowing easy transfer of the apparatus to other geothermal plants. The maximum operating pressure and temperature of the unit are 15 bar and 150 °C, respectively. The scientific and technical purpose of the system is to monitor a compositional variability of the produced fluid and chemical processes potentially occurring within the plant. These may result from reactions between the fluid and the surrounding materials, e.g., corrosion. Also, mineral precipitation as a consequence of temperature and/or pressure decrease or oxygen contamination may occur. This information is of paramount importance as so induced reactions might lead to failure of plant components or may damage the geothermal reservoir upon fluid reinjection and thus decrease injectivity.  相似文献   

The SAURON project – I. The panoramic integral-field spectrograph     

R. Bacon  Y. Copin  G. Monnet  Bryan W. Miller  J.R. Allington-Smith  M. Bureau  C. Marcella Carollo  Roger L. Davies  Eric Emsellem  Harald Kuntschner  Reynier F. Peletier  E.K. Verolme  P. Tim de Zeeuw 《Monthly notices of the Royal Astronomical Society》2001,326(1):23-35

A new integral-field spectrograph, SAURON, is described. It is based on the TIGER principle, and uses a lenslet array. SAURON has a large field of view and high throughput, and allows simultaneous sky subtraction. Its design is optimized for studies of the stellar kinematics, gas kinematics, and line-strength distributions of nearby early-type galaxies. The instrument design and specifications are described, as well as the extensive analysis software which was developed to obtain fully calibrated spectra, and the associated kinematic and line-strength measurements. A companion paper will report on the first results obtained with SAURON on the William Herschel Telescope.  相似文献   

The SAURON project – III. Integral-field absorption-line kinematics of 48 elliptical and lenticular galaxies   总被引：1，自引：0，他引：1  

Eric Emsellem  Michele Cappellari  Reynier F. Peletier  Richard M. McDermid  R. Bacon  M. Bureau †  Y. Copin  Roger L. Davies  Davor Krajnovi&#;  Harald Kuntschner  Bryan W. Miller  P. Tim de Zeeuw 《Monthly notices of the Royal Astronomical Society》2004,352(3):721-743

  相似文献