Hull, A.G. 1982 Trig site stability report, Wairarapa-Karamea. Lower Hutt: New Zealand Geological Survey. New Zealand Geological Survey report EDS 81 45 p.
Abstract: Part of the Royal Society Earth Deformation Studies Programme us the extension and reobservation of the first order geodetic survey network. This survey network from eastern Wairarapa to Karamea (Fig 1) includes many existing first order stations and several new stations specially established or upgraded. Smaller firs order networks in the Wellington and Marlborough Regions have already been reobserved for earth deformation studies, and several marks within these are also included in the larger network (Otway 1972, 1973; Bibby, 1975). The purposes of this survey network are to update existing first order triangulation and to establish a pattern crossing the lowermost part of the North Island and uppermost South Island, which can be used to establish secular rates and directions of horizontal earth deformation. To ensure that any observed changes are the result of crustal movement and not topographic or geological instability, it is important that all trig stations are founded in geologically stable sites where potential and any past instability can be assessed. This report subjectively assesses the stability of all actual and several proposed trig sites for the Wairarapa to Karamea survey network. Criteria for site stability grading are presented in Table 1 and are based on field observation of foundation materials, topographic and geological settings. Aerial photographs and existing geological records have been used to supplement field data. Not all sites were visited and several reports are prepared from data supplied by Lands and Survey staff when upgrading of the station was carried out (auth)
