Constraints on the timing of extension in the Northern Basin, Ross Sea

摘要: Recent kinematic constraints for the region north of western Ross Sea suggest that there was approximately 150 km seafloor spreading in Adare Basin, northeast Cape Adare, between Chrons 20 and 8 (43 to 26 Ma). This history has important implications since extension Basin occurred immediately along strike from Northern Sea, whose extensional is not well known. paper examines transition structures speculates on manner which accommodated Sea. Magnetic anomaly data document a sequence anomalies 18 12 formed during period very slow spreading. The easternmost part this sequence, 16 18, coalesces into single positive near 72° S, forming distinct can be traced southward across continental margin down east side latitude roughly 73° S. observation tectonic it suggests most continued Basin. This, turn, by combination crustal thinning massive, narrowly focused intrusions.