Banded iron formation (?) at Grunehogna Craton, East Antarctica - constraints from aeromagnetic data
We report a strong magnetic high over the Giæverryggen at the Grunehogna craton in western DronningMaud Land, East Antarctica. The anomaly was coarsely mapped by previous surveys. Recently acquiredmagnetic data (2012/13) better constrain its spatial extent and permit the estimate of a theoretical am...
| Published in: | Precambrian Research |
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| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
ELSEVIER SCIENCE BV
2014
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| Subjects: | |
| Online Access: | https://epic.awi.de/id/eprint/36588/ https://hdl.handle.net/10013/epic.44386 |
| Summary: | We report a strong magnetic high over the Giæverryggen at the Grunehogna craton in western DronningMaud Land, East Antarctica. The anomaly was coarsely mapped by previous surveys. Recently acquiredmagnetic data (2012/13) better constrain its spatial extent and permit the estimate of a theoretical ampli-tude value of +4000 to +4200 nT at bedrock surface. From the magnetic data, we estimated a minimummagnetic susceptibility in a spherical source body with a midpoint depth of ∼5.6 km to be greater than193 × 10−3SI, in the absence of relevant remanent magnetization. An exemplary 2.75-D forward mod-eling is carried out. Comparisons with neighboring magnetic highs in a plate tectonic reconstruction ofwestern Dronning Maud Land and southern Africa reveal clear similarities to the magnetic signature ofthe Paleoproterozoic banded iron formation in the Mhlapitsi fold and thrust belt near Polokwane (for-merly Pietersburg) in South Africa, suggesting a similar source for the Giæver Magnetic Anomaly andallow the interpretation that both regions were juxtaposed in Archaean and Paleoproterozoic times. |
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