Twenty-one granite samples (several Kg each) were collected for fission-track dating at various elevations in the lower Wright Valley and along the McMurdo Sound coast between Gneiss Point and Spike Cape.

Field observations suggest that step faulting on a number of different faults may be important in controlling the eastern front of the Transantarctic Mountains in this area (Fig. 9). Fission-track ages of apatites from these samples were reported at the Fourth International Symposium on Antarctic Earth Sciences, and confirm the step-like nature of the faulting. They also indicate a steady uplift rate of 15m/m.y. throughout the Mesozoic (Gleadow, 1982).

References

Gleadow, A.J.W., 1982: Fission-track geochronology of granitoids and uplift history of the Transantarctic Mountains, Victoria Land, Antarctica (abs.). Fourth International Symposium on Antarctic Earth Science, Adelaide, August 16-20.

Figure 9: Latitudinal section through Mt. Doorly, showing the step-like nature of the faulting in the basement near the Victoria Land coast.