Regional crustal structure, fluid and metal transport pathways of Otago illuminated by geophysics

摘要

Most minerals research in the Otago Schist has focused on deposit scale and the immediate environs of deposits. This research has been primarily two-dimensional (map-view) and confined to near-surface outcrops and shallow historic mines, although the Macraes mine is now providing some views of the upper kilometre. Geophysical methods can help to increase knowledge of the three-dimensional (3D) structure and rock properties, albeit with lower resolution than direct observations. Recent passive seismic gathered in the southern South Island has provided some new insights on the regional scale structure, fluid content, and rock properties of the schist belt using the 3D distribution of P- and S- seismic wave velocities and attenuation (Eberhart-Phillips et al. 2018; Reyners et al. 2017).