Blick, G.H. 1990 Ostler Fault Zone : relevelling of the Glen Lyon Road and Trig Z levelling routes and results of dislocation modelling. Lower Hutt: New Zealand Geological Survey. New Zealand Geological Survey report EDS 130 22 p.
Abstract: The Glen Lyon Road and Trig Z levelling routes, installed in the mid 1960's to monitor vertical deformation across the Ostler fault zone, have been surveyed eight times since installation. The results from the latest survey, made in November 1989 are analysed and compared with earlier surveys. Although systematic errors are present in some of the data, the vertical changes recorded across the fault zone are larger than these errors and show vertical deformation associated with the fault zone. This deformation consists of uplift and buckling about the Ruataniwha and Y fault traces. Little deformation is associated with the Hayburn fault trace. The rate of uplift for the period 1966-1973 (0.6-1.0 mm/yr) is approximately twice that for the period 1980-1989 (c. 0.4 mm/yr). A preliminary attempt to model the data as creep on a dislocation plane shows that it is very shallow seated and occurring on a reverse fault with a shallow dip to the west. The dip is consistent with geological evidence.
