Structural Controls on Shallow Cenozoic Fluid Flow in the Otago Schist, New Zealand

Figure 1

Geological setting of the field areas. (a) Simplified map of the South Island of New Zealand showing the Otago Schist and Alpine Schist. (b) Map showing the distribution of metamorphic facies in the Otago Schist, metamorphic terranes, the Chrystalls Beach Complex, and the Akatore Fault, together with the field locations at Akatore Creek and Bruce Rocks. Stereoplot in the bottom-left corner illustrates the modern-day strike-slip stress field in Otago and Canterbury as reconstructed from earthquake focal mechanisms and borehole breakout data (after [39] and [41]). (c) Simplified cross-section through the Otago Schist showing the regional scale antiformal structure. Schematic relationship to the Mesozoic accretionary prism is also shown [43].