Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_4079 From the collection of Christchurch City Libraries.
Peter Majende, artist. Madras Street Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_4068 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3987 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3959 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3993 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3956 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3969 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3953 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_4062 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_4008 From the collection of Christchurch City Libraries.
Removal of the earthquake damaged footbridge over the Avon at Medway Street. Tuesday 12 February 2013. File reference: CCL-2013 -02-12-untitled6.bmp From the collection of Christchurch City Libraries.
Removal of the earthquake damaged footbridge over the Avon at Medway Street. Tuesday 12 February 2013. File reference: CCL-2013 -02-12-untitled7.bmp From the collection of Christchurch City Libraries.
Removal of the earthquake damaged footbridge over the Avon at Medway Street. Tuesday 12 February 2013. File reference: CCL-2013 -02-12-untitled8.bmp From the collection of Christchurch City Libraries.
Removal of the earthquake damaged footbridge over the Avon at Medway Street. Tuesday 12 February 2013. File reference: CCL-2013 -02-12-untitled3.bmp From the collection of Christchurch City Libraries.
Removal of the earthquake damaged footbridge over the Avon at Medway Street. Tuesday 12 February 2013. File reference: CCL-2013 -02-12-untitled.bmp From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3984 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_4021 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3989 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3973 From the collection of Christchurch City Libraries.
Peter Majende, artist. Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3997 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_4019 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_3982 From the collection of Christchurch City Libraries.
Removal of the earthquake damaged footbridge over the Avon at Medway Street. Tuesday 12 February 2013. File reference: CCL-2013 -02-12-untitled2.bmp From the collection of Christchurch City Libraries.
Removal of the earthquake damaged footbridge over the Avon at Medway Street. Tuesday 12 February 2013. File reference: CCL-2013 -02-12-untitled5.bmp From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_4006 From the collection of Christchurch City Libraries.
Removal of the earthquake damaged footbridge over the Avon at Medway Street. Tuesday 12 February 2013. File reference: CCL-2013 -02-12-untitled4.bmp From the collection of Christchurch City Libraries.
None
Measurement of basement seismic resonance frequencies can elucidate shallow velocity structure, an important factor in earthquake hazard estimation. Ambient noise cross correlation, which is well-suited to studying shallow earth structure, is commonly used to analyze fundamental-mode Rayleigh waves and, increasingly, Love waves. Here we show via multicomponent ambient noise cross correlation that the basement resonance frequency in the Canterbury region of New Zealand can be straightforwardly determined based on the horizontal to vertical amplitude ratio (H/V ratio) of the first higher-mode Rayleigh waves. At periods of 1-3 s, the first higher-mode is evident on the radial-radial cross-correlation functions but almost absent in the vertical-vertical cross-correlation functions, implying longitudinal motion and a high H/V ratio. A one-dimensional regional velocity model incorporating a ~ 1.5 km-thick sedimentary layer fits both the observed H/V ratio and Rayleigh wave group velocity. Similar analysis may enable resonance characteristics of other sedimentary basins to be determined. © 2013. American Geophysical Union. All Rights Reserved.
Wednesday 6 February 2013. File reference: CCL-2013 -02-06IMG_2942 From the collection of Christchurch City Libraries.
Friday 22 February 2013. File reference: CCL-2013 -02-22-IMG_4022 From the collection of Christchurch City Libraries.