Reyners, M.E.; Stuart, G. 2002 The central North Island passive seismic experiment . Lower Hutt: Institute of Geological & Nuclear Sciences. Institute of Geological & Nuclear Sciences science report 2002/11 38 p.
Abstract: From 08 January to 27 June 2001, 74 portable digital seismographs were deployed in the central North Island of New Zealand. Thirty-two of these seismographs had broadband seismometers. This deployment, known as CNIPSE (for Central North Island Passive Seismic Experiment), was a major international collaborative project, involving researchers and equipment from the Institute of Geological & Nuclear Sciences, The University of Leeds, and Victoria University of Wellington. The seismograph network covered a 150 km-wide corridor down the dip of the subducted Pacific plate, from Hawke’s Bay to the southern Waikato region, and filled a gap in previous dense seismograph deployments along the Hikurangi subduction zone. The experiment coincided with the North Island Geophysical Transect (NIGHT), a major active source onshore-offshore transect across the central North Island. CNIPSE was designed to study the seismicity, structure and tectonics of the subduction zone in fine detail, from the forearc in Hawke’s Bay to the backarc in the southern Waikato region. The network operated very well, and data recovery was excellent. During the experiment over 4700 earthquakes were located within or close to the seismograph network. These extend down to 270 km depth, and provide an excellent snapshot of seismicity within the Hikurangi subduction zone. This report summarises the scientific objectives and experimental design of the project, as well as the field operations. It provides details of the seismograph stations deployed. It also describes the data processing that has been carried out to date, and the availability of both the broadband and short-period seismic data. Preliminary results from the short-period data are also presented. (auth)