Premium
Origin of the in situ stress field in south‐eastern Australia
Author(s) -
Sandiford Mike,
Wallace Malcolm,
Coblentz David
Publication year - 2004
Publication title -
basin research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.522
H-Index - 83
eISSN - 1365-2117
pISSN - 0950-091X
DOI - 10.1111/j.1365-2117.2004.00235.x
Subject(s) - geology , stress field , seismology , plate tectonics , tectonics , induced seismicity , unconformity , submarine pipeline , fault (geology) , late miocene , slip (aerodynamics) , quaternary , strain partitioning , paleontology , structural basin , oceanography , physics , finite element method , thermodynamics
The in situ stress field of south‐eastern Australia inferred from earthquake focal mechanisms and bore‐hole breakouts is unusual in that it is characterised by large obliquity between the maximum horizontal compressive stress orientation ( S Hmax ) and the absolute plate motion azimuth. The evolution of the neotectonic strain field deduced from historical seismicity and both onshore and offshore faulting records is used to address the origin of this unusual stress field. Strain rates derived from estimates of the seismic moment release rate (up to ∼10 −16 s −1 ) are compatible with Quaternary fault–slip rates. The record of more or less continuous tectonic activity extends back to the terminal Miocene or early Pliocene (10–5 Ma). Terminal Miocene tectonic activity was characterised by regional‐scale tilting and local uplift and erosion, now best preserved by unconformities in offshore basins. Plate‐scale stress modelling suggests the in situ stress field reflects increased coupling of the Australian and Pacific Plate boundary in the late Miocene, associated with the formation of the Southern Alps in New Zealand.