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Processed seismic data of Cruise SO161 SPOC 2001

Within the frame of the comprehensive SPOC project (Subduction Processes off Chile) the SONNE cruises SO161 Leg 2 and 3 have been conducted between October 16th and November 29th, 2001, off central Chile between 28° and 44° S. In that period some 5,300 km were surveyed with multichannel seismic (MCS) reflection, magnetic, gravity, high-resolution bathymetric and echographic methods. In addition, approximately 3,900 km were surveyed with the same spectrum of methods but without MCS. The total number of 2D profiles was 48. Target was the variation of the subduction properties between the convergent oceanic Nazca and continental Southamerica plates and the different conditions that might influence the subduction process as there are: (1) age of the oceanic crust, (2) its structure and composition, (3) its sedimentary cover, (4) its thermal state, (5) the subduction angle and obliquity, and (6) the terrigenous sediment afflux from the continent. Furthermore, special focus was given to the subduction front, the subduction interface, the structure of the slope as well as to the forearc basin structure and history, and the general distribution of gas hydrate indicating bottom simulating reflectors (BSR's). The results are to be compared with previous studies of the Chilean active margin, e.g. CONDOR (SO 101 and 103) and CINCA (SO 104). The SPOC target area was subdivided into three sub-areas A,B and C. One area was chosen for a detailed survey by aid of a narrowly spaced grid and for a close link with a lot of partners. This area is characterized by a distinctly different margin type south of it is assumed. Moreover, the subducting portion of the aseismic Juan Fernandez Ridge is located in that area representing another important target of the survey. Advantageous conditions enabled the survey of an east-west profile south of Chiloé Island, providing a section through the submerged coastal Cordillera into the flooded longitudinal valley. Some results of Leg 2 and 3 are: In all areas A, B and C no subduction bulge (outer high) in the oceanic crust was visible perhaps due to the shortness of the profiles. The sedimentary cover of the oceanic crust is exceptionally thin, and the crustal thickness is generally quite "normal" with around 7 km derived from relatively weak Moho reflections. In area B a so far magnetically unmapped region was filled providing reliable ages of the oceanic crust, and suggesting that the Challenger Fracture Zone abruptly terminates west of the area of investigation. The survey in area C yielded valuable information on the trench morphology. The so far unique MCS profile south of Chiloé island shows a very wide trench and allows to extrapolate the general conditions encountered an area A southward to approximately 44° S. It can be stated that the situation is in sharp contrast to the basin structures detected by industry profiles further north in the Golfo de Corcovado.

Behaviour of mercury and mercury compounds at the underground disposal in salt formations and their potential mobilisation by saline solutions

Within the next 40 years, in the European Union approximately 11,000 t of metallic mercury has to be disposed that is no longer used in the chlor-alkali industry or is gained from non-ferrous metal production or the cleaning of natural gas. One disposal option is permanent storage in underground storage sites in salt rock. As a liquid, metallic mercury has been ex-cluded from this disposal option so far. Prior to a permit, it is necessary to investigate the par¬ticular challenges for the disposal practice that originate from the specific properties of me¬tallic mercury (liquid state, formation of toxic gases, laborious clean-up of contaminated areas). On the base of present knowledge a safe permanent storage of metallic mercury in under-ground storage sites is principally feasible. Veröffentlicht in Texte | 07/2014.

Flächen- und Schutzgebietsmanagement durch Stiftungen, Verbände und Vereine

Ehrenamtliches Engagement stellt ein maßgebliches Standbein für den Naturschutz in Deutschland dar. Erste Naturschutzvereine wurden bereits vor mehr als 100 Jahren gegründet und auch Flächenerwerb durch Vereine zur Sicherung bedrohter Gebiete findet seit Langem statt. Nach der deutschen Wiedervereinigung im Jahre 1990 kam es beispielsweise im Kontext des Verkaufs ehemaligen Staatseigentums der DDR auch zur Veräußerung bzw. kostenlosen Übertragung von Naturschutzflächen (sogenanntes Nationales Naturerbe), in dessen Rahmen insbesondere Naturschutz-Stiftungen und -Vereine bzw. -Verbände als neue Flächeneigentümer vielfältige Verpflichtungen übernahmen. Viele Erfolge des Naturschutzes gehen auf diesen kontinuierlichen ehrenamtlichen Einsatz zurück. Diese Sachverhalte waren für das BfN Anlass, im Jahr 2015 auf der Insel Vilm eine Tagung durchzuführen, auf der verschiedene Stiftungen, Vereine und Verbände ihre Erfolge im Flächen- und Gebietsschutz explizit vorstellten. Dieser Band fasst die Ergebnisse der Tagung zusammen.

Environmental control with the aid of sensor technilogies for GAS sensing

Das Projekt "Environmental control with the aid of sensor technilogies for GAS sensing" wird vom Umweltbundesamt gefördert und von Universität Tübingen, Institut für Physikalische und Theoretische Chemie, Abteilung Analytische Chemie durchgeführt. General Information: The objective of the project consists in the finding of new methods for the monitoring of indoor and ambient air quality by using novel types of gas sensors. The project aims to combine the knowledge of partners from EU and CCE/NIS countries in a synergetic research during which a double transfer will take place. The EU countries will transfer modern sensor testing equipment - one set up for routine and response time measurements and one set up for long term measurements - and knowledge about sensor quality requirements, in line with European environmental policy. They also will train young doctoral students of CCE/NIS partners. The CCE/NIS countries will transfer their extensive knowledge about sensitive materials properties and technological methods for obtaining such materials. IPC will ensure the coordination of the project. The gas stations will be constructed in IPC by doctoral students from CCE/NIS partners, under IPC coordination. IPC will train these students in using the gas stations and will transfer all the needed software. IPC will coordinate the change of information between partners and ensure the concentration of their efforts. IPC will also assist the CCE/NIS partners by forming surface spectroscopical studies and testing of their samples. INFM will assist the CCE/NIS partners in their efforts by making bulk spectroscopic analysis of their materials and by coordinating the set up of gas testing stations for long term measurements. The IPTM efforts will concentrate on the study of a new diode-type sensor, which will be operated in the reverse conduction regime. The main advantage of this new sensor will be the control of the sensitivity towards water vapour and reducing gases by means of suitable choice of the reverse applied voltage and of the temperature of operation. The already obtained samples, using tin oxide as sensing material and in a geometry similar to the one of commercial Figaro gas sensors, show stable asymmetric I-V characteristics. IPTM will attempt to use also the materials prepared by SRIPCP and the substrate prepared by AVANGARD. The SRIPCP efforts will go on further to the development of sol-gel technologies for obtaining ceramic sensitive materials on the basis of metal oxides. Sol-gel technique offers a better control of sensors microstructure and a prospective of lowered dimension and as a consequence a low power consumption. It will perform also investigation of the gas-sensitive films to establish the features of the oxide films structure, the electronic states of the elements in the mixed oxide matrix, the character of structure and phase transformation under thermal treatment of oxide films in different gas ambient and the influence of the factors mentioned above on the gas-sensitive properties of the films. ... Prime Contractor: Universität Tübingen, Fakultät Chemie und Pharamazie, Institut für Physikalische und Theoretische Chemie; Tübingen; Germany.

Saferty of actinides in the nuclear fuel cycle, 1992-1994

Das Projekt "Saferty of actinides in the nuclear fuel cycle, 1992-1994" wird vom Umweltbundesamt gefördert und von European Commission, Joint Research Centre (JRC). Institute for Transuranium Elements (ITU) durchgeführt. Objective: To carry out safety studies with nuclear fuels under long-term and off-normal conditions, to evaluate and reduce risks associated with storing and handling actinides, to carry out basic solid state studies on actinides and collect data and bibliographic references on properties and applications of transuranium elements. General Information: Progress to end 1991. The Institute continued efforts to contribute to the safety of nuclear fission by concentrating its research activities on investigations of the behaviour of nuclear fuel after prolonged irradiation and under variable reactor operating conditions. Mechanism for the release of fission products from irradiated fuel were further elucidated, and the formation of particular structural features which may limit the fuel lifetime were better understood. First results of the post-irradiation examination of nitride fuels irradiated in the Fench PHENIX reactor were obtained, demonstrating the technological potential and the limitations of this fuel type. The measurement of the physical fuel properties of nuclear fuels at extremely high temperatures was continued, and first results of the thermal expansion of uranium dioxide for above its melting temperature were obtained. A facility was installed in order to study possibilities of (nuclear) aerosol agglomeration under dynamic conditions in a high-power acoustic field at ultrasonic and audible frequencies. Mixed oxide fuel rods containing minor actinides (MA), which had been irradiated in a fast reactor (PHENIX) in order to study possibilities of MA transmutation, were analysed. Np-based specimens, mostly in the form of single crystals, were prepared for basic experimental solid state physics studies at the Institute and in various overseas and European laboratories. Progress was made in understanding the electronic structure of transuranium elements and their compounds by further development of theories and experimental efforts in high-pressure research and photoelectron spectroscopy. Equipment for Moessbauer spectroscopy and for other physical property measurements at cryogenic temperatures was installed in the new transuranium research user facility. Work to adapt instruments and methods developed at the Institute in the frame of the above programme (fast multi-colour pyrometry and enhancement of industrial filter efficiency) to industrial application was continued, together with partners from industry. Four patent proposals (on acoustically enhanced off-gas scrubbing, on laser-enhanced extraction, on production methods for Ac-225 and Bi-213, and on the preparation of amorphous substances) were filed in 1991. 42 articles in scientific-technical journals were published (or submitted for publication) and 82 lectures were given in conferences on various subjects dealing with the safety of actinides in the nuclear fuel cycle in 1991. Detailed description of work foreseen in 1992 (expected results). Studies of fission product migration ...

Sub project: Viscous flow of magmas from Unzen volcano, Japan - implications for magma mixing and ascent

Das Projekt "Sub project: Viscous flow of magmas from Unzen volcano, Japan - implications for magma mixing and ascent" wird vom Umweltbundesamt gefördert und von Leibniz Universität Hannover, Institut für Mineralogie durchgeführt. In the proposed project the viscosity of magmas of the Unzen volcano in Japan (compositions: rhyodacite to andesite) will be determined at conditions relevant to the local geological situation. Effects of pressure, water content, redox state of iron and degree of crystallization on rheological properties of the magma are of special importance in our studies. At present the influence of these parameters on viscosity of rhyodacitic to andesitic melts can not be modeled due to a lack of reliable experimental data. In the high-viscosity range nearby the glass transition, viscosities will be measured under pressure using a parallel-plate viscometer developed in our institute. Previous measurements were performed only at ambient pressure in this viscosity range. In the low-viscosity range (stable melt), the fallingsphere method will be applied. Combining both methods, the temperature dependence of viscosity can be defined in a large T range. Based on our viscosity measurements and on data from literature we want to develop a viscosity model applicable to melts with rhyolitic to andesitic composition. Using the viscosity data and results on phase equilibria and volatile solubility (project Ho1337/3+7), an attempt will be made to reconstruct the evolution of Unzen magmas from pre-eruptive conditions to the beginning of the eruption.

Freie troposphaerische Aerosole und ihre Vermischung mit der marinen Grenzschicht

Das Projekt "Freie troposphaerische Aerosole und ihre Vermischung mit der marinen Grenzschicht" wird vom Umweltbundesamt gefördert und von Max-Planck-Institut für Kernphysik durchgeführt. Objective: To provide the necessary data to incorporate aerosols into global climate models and to reduce the uncertainty in the calculation of climate forcing by General Information: FREETROPE is one of five projects that together form the European contribution to the experimental phase of IGAC s second Aerosol Characterisation Experiment (ACE-2). The specific task of FREETROPE is to describe one part of the aerosol life cycle in the marine environment and how it is perturbed by anthropogenic emissions. This is accomplished by characterising the aerosol in the free troposphere (FT) of the sub-tropical North Atlantic, and by performing systematic comparisons with the aerosol in the marine boundary layer (MBL). Using the Cessna Citation the FT aerosol is characterised over larger areas. These characterisations will form the basis for process studies in FREETROPE focusing on 1) the nucleation and growth of aerosols in the clean and perturbed FT, and 2) their possible entrainment in the MBL, with subsequent effects on MBL aerosols and cloud processes. A description of these processes together with other processes, e.g. cloud processes, studied in the other ACE-2 projects LAGRANGIAN and HILLCLOUD will give a unique possibility to give a description of the full life cycle of the atmospheric particles. FREETROPE will operate from Tenerife, doing continuous simultaneous measurements at a coastal MBL station (40 m), and a FT station (Izana, 2360 m). The Cessna Citation will complement these measurements with 50 hours of flight hours between 2300 and 12000 m. At the ground sites, the hygroscopic properties and state of mixing will further be investigated. On all platforms aerosol measurements will be complemented with gas measurements to the extent that they provide information about precursors to aerosol formation and condensational growth, or can indicate the origin of air masses. The Citation will carry a unique payload of mass spectrometers and aerosol instrumentation to study nucleation of H2SO4 and possibly other species (NH4Cl, (NH4)H2SO4 and organics) in the free troposphere. The two ground based station form an ideal set up to study the role of FT-MBL entrainment. The measurements will be supported by trajectory analysis, aerosol dynamic modelling and regional scale modelling that will make a first integration of the data. Prime Contractor: Stockholms Universitet, Department of Meteorology; Stockholm; Schweden.

Sub project: Seismological monitoring of the KTB injection project

Das Projekt "Sub project: Seismological monitoring of the KTB injection project" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum durchgeführt. It is proposed to install a temporary seismological network at the KTB site to observe the induced seismicity during the proposed pumping and injection experiments. Precise detection and localization of the induced seismicity will enable investigations on the spatial-temporal evolution of the seismicity and will be a key point to characterize the stress state, fluid transport properties and stability of the rock system around the pumping/injection point. Small aperture arrays will be installed for increasing the signal to noise ratio and lowering the detection threshold. Additional seismometers will be placed in 50m and 500m deep boreholes to further increase the detection level. High precision absolute and relative location methods will be used which exploit the high waveform similarity expected for the induced seismicity. The proposed high-resolution monitoring system will produce 4 GByte on-line data per day which have to be processed in real time during the duration of the whole experiment. It is not possible to setup and operate an adequate system within one year. Hence we suggest a two step procedure to establish a full featured monitoring system and apply within this proposal only for the first part.

Predicting hydrological fluxes in the Haihe river basin using remote sensing and data assimilation methods

Das Projekt "Predicting hydrological fluxes in the Haihe river basin using remote sensing and data assimilation methods" wird vom Umweltbundesamt gefördert und von Forschungszentrum Jülich GmbH, Institut für Bio-und Geowissenschaften (IBG), IBG-3 Agrosphäre durchgeführt. In order to improve the prediction of actual evapotranspiration, groundwater recharge and soil water storage, remotely sensed data and data assimilation methods will be used. In an innovative approach we will focus on the assimilation of soil moisture and leaf area index (LAI) data and comprehensive validation activities on local, footprint and regional scale. The development of the data assimilation system will include a coupling of HYDRUS with SUCROS and CLM with SUCROS and the integration of the radiative transfer model CMEM. We will analyze the advantage of using ensemble Kalman filter (EnKF), particle filter (PF), inverse modeling methods (NSGA-II) and bias correction methods. In addition to the state update of LAI and soil moisture, a parameter update of soil hydraulic properties and root water uptake is performed. By forward model runs virtual soils and regional hydrological systems are simulated to analyze the role of model errors from inaccurate process description and parameterization on the prediction of groundwater recharge and evapotranspiration. The modeling results are validated by experimental studies within the Haihe river basin. On the local scale weighable lysimeters are used to determine groundwater recharge, soil water storage and evapotranspiration. On the footprint scale we determine actual evapotranspiration using eddy covariance systems (EC) and large aperture scintillometer (LAS) which will be compared to remotely sensed evapotranspiration values. To two regions in the Haihe river basin the proposed data assimilation approach will be applied by using multiple remote sensing data. The proposal aims to identify the need and the required accuracy of additional hydrological information that may contribute in constraining the uncertainties of the model parameter space and the model prediction uncertainty, above all over ungauged river basins or in case of reduced data availability. In addition, a monitoring of hydrological fluxes, in particular groundwater recharge and actual evapotranspiration, is performed which will be able to react to rapidly changing environmental conditions and to utilize future mission data (e.g. SMOS, SMAP).

Formation processes and radiative properties of particles in aircraft wakes

Das Projekt "Formation processes and radiative properties of particles in aircraft wakes" wird vom Umweltbundesamt gefördert und von Fraunhofer-Gesellschaft zur Förderung der Angewandten Forschung, Fraunhofer-Institut für Atmosphärische Umweltforschung durchgeführt. Objective: The project aims at a better understanding of the effect of aircraft exhaust on aerosol and cloud formation and of their impact on the climate. It will examine the interaction between aircraft emission (gases and particles), cloud and particles formation and radiative energy transfer in the upper troposphere. For this, the formation of new particles (contrails and aerosols) in the wake of subsonic airplanes will be investigated in order to determine the microphysical and radiative properties of contrails as function of the meteorological conditions during their life cycle, i.e. from the early phase of jet expansion to a cirrus like stage. This project includes the combination of ground based observations by lidar, aircraft 'in situ' observations (Falcon) and numerical modelling. General Information: The structure and evolution of contrails in the wake of subsonic aircraft as well as their interactions with aerosols will be studied by combining in situ measurements, ground observations (LIDAR) and modelling of the wake and of the contrails. For the purpose of in situ measurements, the meteorological research aircraft 'Falcon' of DLR will be operated. To allow an undisturbed inspection of the produced contrail through its life cycle, single commercial aircraft producing a contrail will be guided through the temporary restricted area TRA 307. The deliverables of the project will include: a) Computer codes for modelling of the wakes, modelling of particles formation in the wakes and modelling of the life cycle of contrails in relation with meteorological, properties of the upper atmosphere. b) Data set concerning the ground observation of contrails (by Lidar including altitude of contrails, horizontal and vertical extent, cross-section area, backscatter, optical depth, degree of depolarisation etc.) and the in situ measurements. The in situ measurements will include the basic atmospheric state parameters (temperature, pressure, humidity, solar irradiance) inside and outside the wake, aerosol and cloud particle size distributions, airborne measurements of Cloud Condensation Nuclei (CCN), Cloud/residual properties in the range 0.1-3.5 m, airborne measurements of particles phase function, ambient water vapour content and cloud water content, elemental composition, light absorption measurements, morphology of the particles collected with the counter flow virtual impactor (post flight analyses). c) Final report assessing the influence of aircraft emissions on the physical and atmospheric processes in the upper troposphere, with special emphasis on particles formation, particle and cloud interactions and radiative energy transfer. This final report will also develop parameterisation schemes, describing the formation, evolution and radiative properties to be used in large scale circulation models. Prime Contractor: Centre National de la Recherche Scientifique (CNRS), Centre de Geochimie de la Surface (UPR 6251), Strasbourg; France.

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