Abstract - The spatio-temporal evolution of normal faulting and submarine volcanism during Mid-Miocene-recent times in the Taranaki backarc basin, New Zealand, highlights features related to subduction zone processes. High sedimentation rates have led to the blanketing and preservation of volcanic edifices and normal faults imaged on regional seismic datasets, providing a basis for defining the evolution of fault and volcanic activity. Southward migration of the locus of volcanism and basin extension is linked to steepening and migration of the Hikurangi subduction zone between the Australian and Pacific plates, but volcanic activity shows a more gradual southward progression, compared to the punctuated migration of fault activity and basin location. Stepwise changes in the locus of faulting is attributed to periods of strong coupling between the subducting slab and the overlying crust, with consequences for crustal deformation throughout New Zealand. The spatio-temporal migration of subduction-related faulting and volcanism can, therefore, differ, with neither process controlling the location of the other.
Abstract of talk given to:
Tectonic Studies Group Annual Meeting, Durham (UK), January 2011.