The distribution of strain within a rifting fault network

Assessing the distribution of strain is important for understanding a) processes of fault network growth and b) the distribution of deformation within a fault network, such as fault interactions and associated damage. Therefore, we investigate the spatial and temporal distribution of strain within the active Rangitaiki fault system in the Whakatane Graben, North Island, NZ. Initial analysis shows that there is a change from distributed faulting to localized faulting along the strike of the fault system. Distributed faulting occurs at the NE tip of the fault system, where the Rangitaiki Fault has many younger segments, with extension being accommodated across numerous faults. Whereas, localized faulting occurs where segment linkage is more established, with extension localized onto fewer but larger displacement faults. Syn-rift stratigraphy allows the temporal preservation of strain to be analysed for the past 18Kyr, adding to our understanding of the role of strain localization within fault networks.