Cenozoic continental rifting in the north-western Ross Sea

Marine gravity and seismic data are used to derive a preliminary crustal model for the Central Basin of the northern Ross Sea. The model is consistent with the presence of a thick (8 km) ocean crust. Existing geophysical data indicates the rift forming the Central Basin continues, with offsets, into the Central Trough further south. Using limited existing data on the age (61-53 Ma), and the amount and direction of extension of the Central rift system, an estimate is made of the pole of rotation for 61-53 Ma (79 degrees S, 170 degrees W and rotation 6 degrees). This pole of rotation and those for 43-26 Ma and 26-10 Ma, previously derived, are used to reconstruct the northern Ross Sea margin prior to 61 Ma. The reconstruction shows a close fit of the continental components.