Downhole Physical Properties Measurements Supporting Iron-oxide Deep Exploration and Mining in Blötberget, Sweden
2016 (English)Conference paper, Abstract (Refereed)
Several physical properties including full-waveform triple sonic, natural gamma, susceptibility, formation and fluid conductivity from downhole geophysics as well laboratory measurements (density, RQD and magnetite content) were carried out and analysed in order to characterize iron-oxide mineralization and their host rocks in the Blötberget mining area in south-central Sweden. It was observed that a strong seismic signal from the mineralization would be generated and that full-waveform sonic data could be used as proxy for fracture mapping and rock quality definition. Fracture systems were also believed to generate modest reflectivity from the calculation of reflection coefficients. While properties like magnetite content or density were clearly indicative of the magnetite mineralization, magnetic susceptibility plots indicated little paramagnetic effect; even host rocks showed ferromagnetic behaviour. We attribute this to a general enriched magnetite mineralization in most types of rocks. This observation is interesting since it may allow joint inversion of gravity and magnetic data possible and thus an estimation of the mineralization tonnage and magnetite content.
Place, publisher, year, edition, pages
IdentifiersURN: urn:nbn:se:uu:diva-303366DOI: 10.3997/2214-4609.201602092OAI: oai:DiVA.org:uu-303366DiVA: diva2:971659
Near Surface Geoscience 2016 - First Conference on Geophysics for Mineral Exploration and Mining