Geological structures deduced from airborne geophysical surveys around Syowa Station, Antarctica

• Main Authors: Nogi, Y., Jokat, Wilfried, Kitada, K., Steinhage, Daniel
• Format: Conference Object
• Language: unknown
• Published: 2012
• Subjects: Antarctic; Syowa Station; Yamato; Rayner; Antarc*; Antarctica
• Online Access: https://epic.awi.de/id/eprint/30961/; https://hdl.handle.net/10013/epic.39838

The area around Syowa Station, the Japanese Antarctic station in Lutzow-Holm Bay, is widely considered to be a junction of the Africa, India, Madagascar, and Antarctic continents, according to the reconstruction model of Gondwana. This area is key to investigating the formation of Gondwana. Joint Japanese-German airborne geophysical surveys were conducted around Syowa Station in January 2006 to reveal the tectonic evolution contributing to the formation of Gondwana in this area. Ice radar, magnetic, and gravity data were obtained from onshore areas. Several characteristic features that may be related to the tectonic evolution of Gondwana were inferred primarily from magnetic anomalies and from gravity anomalies and bedrock topography. The boundaries of the Lutzow-Holm Complex, the Yamato-Belgica Complex, and the Western Rayner Complex are defined, but the inland extension of the boundary between the Lutzow-Holm and the Yamato-Belgica Complexes is unknown south of 71S. The main geological structural trends of the Lutzow-Holm Complex derived from magnetic anomalies are NW-SE and are concordant with the geological results in the coastal region. However, nearly NE-SW-trending magnetic anomalies cut across the NW-SW magnetic anomaly trends, and the NE-SW right lateral strike-slip faults are deduced from the magnetic and the gravity anomaly data in the Lutzow-Holm Complex. The Lutzow-Holm Complex is divided into four blocks based on the estimated strike-slip faults. The strike-slip faults were possibly generated during a younger stage of Pan-African orogeny, after the formation of NW-SE-striking geological structures. These results provide new constraints for the formation of Gondwana.