Sökning: "geochemical"

Visar resultat 1 - 5 av 178 avhandlingar innehållade ordet geochemical.

1. 1. Integrated geophysical-geochemical methods for archaeological prospecting

   Författare :Kjell Persson; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geophysics; geophysical; geochemical; prospecting; archaeology; electric; magnetometric; Geofysik; Geophysics; Geofysik;

   Sammanfattning : A great number of field measurements with different methods and instruments were conducted in attempts to develop a method for an optimal combination of various geochemical and geophysical methods in archaeological prospecting. The research presented in this thesis focuses on a study of how different anthropogenic changes in the ground can be detected by geochemical and geophysical mapping and how the results can be presented. LÄS MER

3. 2. Iron and aluminium speciation in Swedish freshwaters : Implications for geochemical modelling

   Författare :Carin Sjöstedt; Jon Petter Gustafsson; Peggy O'Day; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geochemical equilibrium modelling; pH; adsorption to ferrihydrite; metal-NOM complexation; liming; EXAFS spectroscopy;

   Sammanfattning : Speciation governs transport and toxicity of trace metals and is important to monitor in natural waters. Geochemical models that predict speciation are valuable tools for monitoring. They can be used for risk assessments and future scenarios such as termination of liming. LÄS MER

4. 3. Arsenic in Alluvial Aquifers in the Meghna Basin, Southeastern Bangladesh : Hydrogeological and Geochemical Characterisation

   Författare :Md. Aziz Hasan; Prosun Bhattacharya; William Burgess; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Alluvial aquifer; groundwater; arsenic mobilisation; geology; Meghna basin; Bangladesh; Water engineering; Vattenteknik;

   Sammanfattning :  Elevated levels of arsenic (As) in Bangladesh groundwater has emerged as a massive calamity exposing a large population to the risk of As toxicity from drinking water sources and agricultural products. Holocene alluvial aquifers in the delta- and flood-plains of the Ganges-Brahmaputra- Meghna (GBM) river systems are severely affected by high levels of As in groundwater. LÄS MER

5. 4. Computer programs used for geochemical calculations

   Författare :Irene Lundén; Chalmers tekniska högskola; []
   Nyckelord :groundwater; code development; geochemical computer programs; PHREEQE; modelling; cement pore water;

   Sammanfattning : .... LÄS MER

7. 5. Geochemistry of tin, tungsten and molybdenum in Swedish Proterozoic granitoids : its potential use in regional mineral exploration

   Författare :Karl-Magnus Drake; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Granitoid; lithogeochemistry; Sn; W; Mo; Li; geotectonic - chronologic subdivision; geochemical-statistical grouping; uni- and multivariate statistical analysis; computer programs; metallogenic element distributions; Sn-W-concentration patterns; ore-bearing potential; probability calculations; petrometallogenic element ratios; petrochemical trends; postmagmatic alterations; geochemical variability; normative composition; genesis; absolute age; bibliography; analysis databank; Proterozoic; Sweden; N5600 N6800 E2330 E1120;

   Sammanfattning : The primary aim of this broad regional study is to statistically determine the Li-Sn-W-Mo-bearing potential of various granitoids using geochemical criteria.Computer-based, univariate and multivariate statistical methods are applied to major and trace element data from ca 660 granitic rock samples and over 800 major element analyses, selected from the Swedish geological literature. LÄS MER