Sveconorwegian palaeomagnetism in hyperite dolerites and syenites from Scania, Sweden

Abstract

Proterozoic hyperite dolerites and syenites from the Scanian part of the Protogine Zone (Sveconorwegian Front) have the same characteristic remanence direction after alternating field demagnetization. The direction is D = 297.2°, I = −83.8°, α₉₅ = 3.7°, k = 114.6, which gives a palaeopole at 49°S, 211°E, dp = 7.1°, d _m = 8.3°. The pole position, and a majority of K-Ar datings on the rocks studied, implies that they became remagnetized during the Sveconorwegian regeneration. This new remanence was not affected by a later intrusion of a dolerite swarm in the intersecting Fennoscandian Border zone. A tentative apparent polar wander path for the Sveconorwegian is presented.

Key Words:

• Palaeomagnetism
• thermomagnetism
• remagnetization
• demagnetization
• pole positions
• polar wandering
• intrusions
• hyperite dolerite
• syenite
• Sveconorwegian
• Proterozoic
• Protogine Zone
• Tornquist Lineament
• Fennoscandian Border Zone
• Skåne
• southern Sweden
• N5533 N5650 E1484 E1250