Search: onr:"swepub:oai:DiVA.org:uu-163597" >
The upper crustal 3...
The upper crustal 3-D resistivity structure of the Kristineberg area, Skellefte district, northern Sweden revealed by magnetotelluric data
-
- Hübert, Juliane (author)
- Uppsala universitet,Geofysik
-
- García Juanatey, María de los Ángeles (author)
- Uppsala universitet,Geofysik
-
- Malehmir, Alireza (author)
- Uppsala universitet,Geofysik
-
show more...
-
- Tryggavson, Ari (author)
- Uppsala universitet,Geofysik
-
- Pedersen, Laust B (author)
- Uppsala universitet,Geofysik
-
show less...
-
(creator_code:org_t)
- 2012-11-27
- 2013
- English.
-
In: Geophysical Journal International. - : Oxford University Press (OUP). - 0956-540X .- 1365-246X. ; 192:2, s. 500-513
- Related links:
-
https://uu.diva-port... (primary) (Raw object)
-
show more...
-
https://academic.oup...
-
https://urn.kb.se/re...
-
https://doi.org/10.1...
-
show less...
Abstract
Subject headings
Close
- A 3-D model of the crustal electrical resistivity was constructed from the inversion of magnetotelluric data in the Kristineberg area, Skellefte district, the location of one of Sweden's most successful mining activities. Forward modelling of vertical magnetic transfer data supports our model which was derived from the magnetotelluric impedance only. The dominant features in the 3-D model are the strong conductors at various depth levels and resistive bodies of variable thickness occurring in the shallower subsurface. The deepest conductor, previously associated with the Skellefte crustal conductivity anomaly, is imaged in the southern part of the area as a north-dipping feature starting at similar to 4 km depth. Several shallow conductors are attributed to graphite in the black shales defining the contact between the metasedimentary rocks and the underlying metavolcanic rocks. Furthermore, an elongated intermediate depth conductor is possibly associated with alteration zones in the metavolcanic rocks that host the ore occurrences. The most prominent crustal resistors occur in the southern and northern part of the area, where their lateral extent on the surface coincides with the late-orogenic Revsund type intrusions. To the east, a resistive feature can be correlated to the early-orogenic Viterliden intrusion. The 3-D model is compared with two previous 2-D inversion models along two perpendicular profiles. The main electrical features are confirmed with the new model and previous uncertainties regarding 3-D effects, caused by off-profile conductors, can be better assessed in 3-D, although the resolution is lower due to a coarser model discretization. The comparison with seismic sections along two north-south profiles reveals structural correspondence between electrical features, zones of different reflectivity and geological units.
Subject headings
- NATURVETENSKAP -- Geovetenskap och miljövetenskap -- Geofysik (hsv//swe)
- NATURAL SCIENCES -- Earth and Related Environmental Sciences -- Geophysics (hsv//eng)
Keyword
- Crustal structure
- Electrical properties
- Magnetotelluric
- Geophysics with specialization in Solid Earth Physics
- Geofysik med inriktning mot fasta jordens fysik
Publication and Content Type
- ref (subject category)
- art (subject category)
Find in a library
To the university's database