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Karte der oberflächennahen Rohstoffe der Bundesrepublik Deutschland 1:200.000 (KOR200) - CC 7126 Nürnberg

Die Karte oberflächennaher Rohstoffe 1:200.000 (KOR 200) ist ein Kartenwerk, das gemeinsam von der Bundesanstalt für Geowissenschaften und Rohstoffe und den Staatlichen Geologischen Diensten der Länder (SGD) im Auftrag des Bundesministers für Wirtschaft und Arbeit auf Beschluss der Länderwirtschafts­minister vom 22. Juni 1984 erarbeitet wird. Das Kartenwerk folgt dem Blattschnitt der topographischen Übersichtskarte 1:200.000 (TÜK 200) und besteht aus 55 Kartenblättern mit jeweils einem Erläuterungsheft. Es erfolgt eine Bestandsaufnahme, Beschreibung, Darstellung und Dokumentation der Vorkommen und Lagerstätten von mineralischen Rohstoffe, die üblicherweise im Tagebau bzw. an oder nahe der Erdoberfläche gewonnen werden. Im Besonderen sind dies Industrieminerale, Steine und Erden, Torfe, Braunkohle, Ölschiefer und Solen. Die Darstellung der oberflächennahen Rohstoffe und die zusätzlichen schriftlichen Informationen sind für die Erarbeitung überregionaler, bundesweiter Planungsunterlagen, die die Nutzung oberflächennaher mineralischer Rohstoffe berühren, unentbehrlich. Auf der Karte sind neben den umgrenzten, je nach Rohstoff farblich unterschiedlich dargestellten Lagerstätten- bzw. Rohstoffflächen "Abbaustellen" (=Betriebe) bzw. "Schwerpunkte mehrerer Abbaustellen" mit je einem Symbol dargestellt. Die Eintragungen in der Karte werden ergänzt durch Texterläuterungen. Die Erläuterungsbände haben üblicherweise einen Umfang von 40 - 80 Seiten und sind derzeit nur in der gedruckten Ausgabe der Karte verfügbar. Der Text ist gegliedert in: - Einführung - Beschreibung der Lagerstätten und Vorkommen nutzbarer Gesteine - Rohstoffwirtschaftliche Bewertung der Lagerstätten und Vorkommen oberflächennaher Rohstoffe im Blattgebiet - Verwertungsmöglichkeiten der im Blattgebiet vorkommenden nutzbaren Gesteine - Schriftenverzeichnis - Anhang (u. a. mit Generallegende und Blattübersicht) Die KOR 200 stellt somit die Rohstoffpotentiale in Deutschland in bundesweit vergleichbarer Weise dar und liefert eine Grundlage für künftige Such- und Erkundungsarbeiten sowie einen Beitrag zur Sicherung der Rohstoffversorgung.

Drained ring-shear test data of wet silica powder-glass beads-PVC powder mixture “CM2” used for analogue modelling in the laboratory for experimental tectonics (LET) at RomaTre University, Rome, Italy

Abstract

Biogenic silica - total fraction

Biogenic silica in the total fraction in % in the German Baltic Sea. For further information look at the link map instruction.

Biogenic silica - fine fraction

Biogenic silica in the fine fraction in % in the German Baltic Sea. For further information look at the link map instruction.

Ermittlung der Unsicherheiten in der Strahlenexpositionsabschätzung in der Wismut-Kohorte - Teil 2 - Vorhaben 3618S12223

The Wismut cohort consists of a sample of 58 974 male employees from around 400 000 former employees of the Wismut company. The employees were exposed to various occupational exposures ranging from exposure to ionizing radiation through radon and its progeny, uranium dust and external gamma radiation to silica dust, arsenic and diesel exhaust. It constitutes one of the largest cohorts of uranium miners who were occupationally exposed to radon. When the cohort was established, individual exposure estimates for radon progeny were reconstructed through a Job Exposure Matrix (JEM) which provides information on the annual exposure for a hewer with 2000 working hours. In the early years of exposure in the Wismut cohort (1946 – 1954/55), there were no systematic exposure assessment, and exposure values received in this period therefore had to be reconstructed retrospectively by experts. Due to a lack of exposure information, it was however impossible to reconstruct the exposure values for each object and year independently. Starting in 1954/55, there was exposure monitoring for underground mining objects in the Wismut cohort based on measurements of radon gas concentration (1955/56 - 1965 in Saxony and 1955/56 - 1974 in Thuringia) and radon progeny concentration (1966 - 1990 in Saxony and 1975 - 1990 in Thuringia). In this exposure assessment period, measurements were taken in each year and object to estimate a mean annual radon gas concentration and radon progeny concentration, respectively. Radon gas or radon progeny estimates were multiplied by a working time factor, an activity weighting factor, and either an equilibrium factor (for radon gas concentration measurements) or a ventilation correction factor (for radon progeny concentration measurements). Part 2 of the research project “Determination of uncertainties of radiation exposure assessment in the Wismut cohort” included the following tasks: (1) Quantification of uncertainty, (2) Definition of measurement models and development of an approach to correct for measurement error, (3) Design and implementation of a simulation study to compare the proposed approach with simulation extrapolation and regression calibration, and (4) Application to the data of the Wismut cohort without accounting for effect modifying variables and excluding workers who were employed in Wismut processing companies at any point during their working career.

Markt für Quarzsand

technologyComment of cryolite production, from fluosilicic acid (GLO): The main production of cryolite involves hydrofluoric acid or fluosilicic acid. In both cases, the reactants can be combined with a variety of materials, such as Al2O3 · 3 H2O, Al2O3 · x NaOH, NaOH, NaCl, and Na2SO4. During the present reaction, fluosilicic acid is neutralised with sodium hydroxide. Then it reacts with Al2O3 to produce cryolite and silica. The reaction process is shown below: Al2O3 + 2H2SiF6 + 6 NaOH --> 2 Na3AlF6 + 2 SiO2 + 5 H2O It is difficult to predict how much of the cryolite is produced with the present reaction, since many production routes exist. The present inventory serves as an illustration of the cryolite production from fluosilicic acid. The alternative production route with HF is still considered to be the main production route (source: Ullmann encyclopedia, Cryolite, 2005). technologyComment of silica sand production (DE, RoW): Generally there are no differences in the quarrying process of silica sand compared to the “normal” sand process. An important difference is that silica sand is dried. It is assumed that the content of moisture before drying is about 5% and afterwards around 1%. Another difference is based on the high content of SiO2, which makes the raw material rarer. Losses in the conveyor belt transportation are taken into account.

Bacterial communities in winter

Transition in bacterial communities along the 2000 km salinity gradient of the Baltic Sea in winter.

Bacterial communities in summer

Transition in bacterial communities along the 2000 km salinity gradient of the Baltic Sea in summer.

Markt für Wasser, deionisiert

technologyComment of water production, deionised (Europe without Switzerland): The process includes an anionic resion or combined cation/anion exchange resin. The unit is operated with counterflow regeneration. Obtained water quality: about 1-0.1 uS/ cm for the conductivity and a silica content (as SiO2) of 5-25 ug/l. For the water source, tap water from a public supply with a total hardness of 1.71 mol/m3 (range 0.7 - 3.2) was assumed. Reference: Althaus H.-J., Chudacoff M., Hischier R., Jungbluth N., Osses M. and Primas A. (2007) Life Cycle Inventories of Chemicals. ecoinvent report No. 8, v2.0. EMPA Dübendorf, Swiss Centre for Life Cycle Inventories, Dübendorf, CH.

Emissionsmessungen von alveolengängigem kristallinen Siliziumdioxid (RCS) an Industrieanlagen

The potential risk from human exposure to Respirable Crystalline Silica (RCS) includes a range of serious non-malignant effects as well as lung cancer, which may occur at relatively low levels. In a previous study, investigating several industrial sectors, we found the highest emission levels of RCS in the industrial silica sand operations. 28 different sand processing facilities were examined in two complex emission measurement programmes. A two-stage cascade impactor was used to separate the particle fractions: > 10 Ìm, 10-4 Ìm and < 4 Ìm of aerodynamic diameter. The size of particles of most concern is the so-called particulate matter 4 (PM4). The analytical procedure for determining RCS in emission samples consists of using X-ray diffraction and infrared spectroscopy methods. The relationship between Total Particulate Matter (TPM), PM4 and RCS (as a percentage of PM4) was evaluated. In the case of increased Total Particulate Matter concentration in the stack gas (more than 20 mg/m3) combined with increased percentage of RCS in PM4 an exceedance of an Emission Limit Value (ELV) of 1 mg/m3 is more likely to occur. The evaluation of the emission data helped to formulate differentiated emission control requirements of the plants concerning the draft of the new German Technical Instructions on Air Quality Control (new German TA Luft). It was possible to demonstrate, under which conditions for the specific processing techniques used, emission limits for Total Particulate Matter can be used as a threshold value for the Respirable Crystalline Silica emission. If the mass fraction of quartz in the source rock to be processed is more than 20%, periodic measurements of Respirable Crystalline Silica will be necessary every three years on grinders, whereas they will be only necessary on dryers if the Total Dust concentration exceeds 5 mg/m3. © 2021, VDI Fachmedien GmBH & Co. KG. All rights reserved.

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