Publication Date:
2017-10-17
Description:
The ice shield of Antarctica, which measures several kilometers in thickness, presents a challenge when
attempting to unravel the subglacial geology. Here, we report about systematic airborne magnetic surveys
conducted over the last decade, which investigated a significant part of Dronning Maud Land (DML), imaging
for the first time the crustal architecture of the interior of this sector of East Antarctica. High-resolution data reveal
parallel, elongated magnetic anomalies in southeastern DML. These NW–SE trending anomalies can be
traced farther east into sparser Russian magnetic data sets. Several high amplitude magnetic anomalies with
values above 400 nT have been observed in southwesternDML and Coats Land. They differ clearly inwavelength
and amplitudes fromthe magnetic pattern found in the east and do not show any evidence of a Pan-African orogenic belt or suture zone connecting the Shackleton Range with easternDML, as hypothesized in several studies.
This leads to the assumption of the existence of a hitherto unrecognized large tectonic province in southeastern
DML.Whereas an over 100 km long magnetic lineament in the interior of the DronningMaud Landmay reflect a
major shear zone akin to the Pan-African age Heimefrontfjella shear zone. Both findings bring new evidences to
the still open question about the amalgation of East and West Gondwana. In addition, the magnetic data allow
mapping the eastern extent of the presumable cratonic province of Coats Land, a region considered as a key
piercing point for reconstructions of Rodinia. Furthermore, the Beattie Magnetic Anomaly in southern Africa is
assumed to continue into East Antarctica. Two magnetic highs in western DML are identified as possible eastward
continuation of this prominent anomaly.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
Format:
application/pdf
Format:
application/pdf
