Variable In Situ Stress Orientations Across the Northern Hikurangi Subduction Margin

Autor: P. Barnes, H. Lee, Effat Behboudi, M. Paganoni, Katerina Petronotis, Leah J. LeVay, David D. McNamara, Ake Fagereng, Ingo Pecher, Heather M. Savage, Laura M. Wallace, Demian M. Saffer, Hung Yu Wu, Ann E. Cook, G. Kim
Rok vydání: 2021
Předmět:
Zdroj: Geophysical Research Letters
ISSN: 0094-8276
DOI: 10.1029/2020gl091707
Popis: We constrain orientations of the horizontal stress field from borehole image data in a transect across the Hikurangi Subduction Margin. This region experiences NW‐SE convergence and is the site of recurrent slow slip events. The direction of the horizontal maximum stress is E‐W at an active splay thrust fault near the subduction margin trench. This trend changes to NNW‐SSE in a forearc trench slope basin on the offshore accretionary wedge, and to NE‐SW in the onshore forearc. Multiple, tectonic, and geological processes, either individually or in concert, may explain this variability. The observed offshore to onshore stress rotation may reflect a change from dominantly compressional tectonics at the deformation front, to a strike‐slip and/or extensional tectonic regime closer to the Taupo Volcanic Zone, further inland. In addition, the offshore stress may be affected by topography and/or stress rotation around subducting seamounts, and/or temporal stress changes during the slow slip cycle.
Databáze: OpenAIRE