Search

found 9 results

Images for location; more images...

Research papers, University of Canterbury Library

This paper presents site-specific and spatially-distributed ground-motion intensity estimates which have been utilized in the aftermath of the 2010-2011 Canterbury, New Zealand earthquakes. The methodology underpinning the ground motion intensity estimation makes use of both prediction models for ground motion intensity and its within-event spatial correlation. A key benefit of the methodology is that the estimated ground motion intensity at a given location is not a single value but a distribution of values. The distribution is comprised of both a mean and standard deviation, with the standard deviation being a function of the distance to nearby observations at strong motion stations. The methodology is illustrated for two applications. Firstly, maps of conditional peak ground acceleration (PGA) have been developed for the major events in the Canterbury earthquake sequence, which among other things, have been utilized for assessing liquefaction triggering susceptibility of land in residential areas. Secondly, the conditional distribution of response spectral ordinates is obtained at the location of the Canterbury Television building (CTV), which catastrophically collapsed in the 22 February 2011 earthquake. The conditional response spectra provide insight for the selection of ground motion records for use in forensic seismic response analyses of important structures at locations where direct recordings are absent.

Articles, UC QuakeStudies

This report provided information on the location and character of the Ostler Fault Zone near Twizel. The fault traces, and associated recommended fault avoidance zones, were mapped in detail for inclusion in a District Plan Change for the Twizel area. The Ostler Fault Zone was mapped in detail because of the higher likelihood of movement on that fault than others in the district, and the potential for future development across the fault zone because of its proximity to Twizel. See Object Overview for background and usage information. The report recommended that the information be incorporated into the District Plan Change and that site-specific investigations be undertaken before development is allowed within the fault avoidance zones. These recommendations were taken up by Mackenzie District Council.

Articles, UC QuakeStudies

This report provides information on the locations and character of active geological faults and folds in Mackenzie District. The faults are mapped at a district scale and the information is intended to highlight areas where there is a risk of fault movement, and where more detailed investigations should be done if development is proposed in that area(depending on the potential activity of the fault and the type of development proposed). Most of the faults and folds identified at the ground surface in Mackenzie District are in rural or very sparsely populated areas. In addition, most of the faults have relatively long recurrence intervals (long-term average time between fault movements) in the order of several thousand years. Following the Ministry for the Environment Active Fault Guidelines, normal residential development would be allowed on or near faults with recurrence intervals this long. There are no recommendations associated with this report. The information in the report will be reviewed as required, after the remaining district reports are completed in the region. See Object Overview for background and usage information.

Research papers, University of Canterbury Library

A team of earthquake geologists, seismologists and engineering seismologists from GNS Science, NIWA, University of Canterbury, and Victoria University of Wellington have collectively produced an update of the 2002 national probabilistic seismic hazard (PSH) model for New Zealand. The new model incorporates over 200 new onshore and offshore fault sources, and utilises newly developed New Zealand-based scaling relationships and methods for the parameterisation of the fault and subduction interface sources. The background seismicity model has also been updated to include new seismicity data, a new seismicity regionalisation, and improved methodology for calculation of the seismicity parameters. Background seismicity models allow for the occurrence of earthquakes away from the known fault sources, and are typically modelled as a grid of earthquake sources with rate parameters assigned from the historical seismicity catalogue. The Greendale Fault, which ruptured during the M7.1, 4 September 2010 Darfield earthquake, was unknown prior to the earthquake. However, the earthquake was to some extent accounted for in the PSH model. The maximum magnitude assumed in the background seismicity model for the area of the earthquake is 7.2 (larger than the Darfield event), but the location and geometry of the fault are not represented. Deaggregations of the PSH model for Christchurch at return periods of 500 years and above show that M7-7.5 fault and background source-derived earthquakes at distances less than 40 km are important contributors to the hazard. Therefore, earthquakes similar to the Darfield event feature prominently in the PSH model, even though the Greendale Fault was not an explicit model input.