Research project: Fluid flow associated with the Alpine Fault, South Island, New Zealand
Currently Active:
Yes
The Alpine Fault marks the transpressional Pacific-Australian Plate Boundary that runs through South Island, New Zealand. Continental collision at such plate boundaries affects crustal growth, deformation, the formation of mineral resources and natural hazards. The impact of fluid flow in these zones depends upon fluid sources, flow paths, temperatures and extent of fluid-rock interaction.
Project Overview
Block Model of the Southern Alps
This study uses the geochemical analysis of hydrothermal vein minerals, warm springs and surface waters to constrain fluid flow in the Alpine Fault Zone and Southern Alps of New Zealand.
Why study the Alpine Fault?
The Alpine Fault ruptures every 329±68 years the last rupture was ~300 years ago, therefore it is late in its seismic cycle
Rapid uplift and asymmetric erosion has exhumed deeply formed rocks adjacent to the fault exposing a ~25 km crustal section
The orogen is young and presently active therefore seismicity and tectonics are relatively well constrained
Warm springs emanate from the Southern Alps allowing sampling of modern day geothermal fluids
Areas in the Southern Alps are mineralised with gold
Study samples
Scientific aims:
To measure elemental concentrations and isotopic ratios of geothermal fluids and vein minerals from various crustal depths to:
Constrain sources of fluids and the depth of penetration of meteoric water in the Alpine Fault Zone
Constrain water-rock ratios and temperatures of fluid-rock interactions at different structural depths in the Alpine Fault Zone
Constrain fluid flow paths
Test for links between shallow and deep level fluid flow systems
Southern Alps Cross Section
Funding
This project was funded until October 2012 by a NERC-CASE PhD studentship (NE/G524160/1) linked with GNS Science, New Zealand, a NERC small grant (NE/H012842/1) to Prof. Damon Teagle, and a NIGFSC grant (IP-1187-0510) for work at the NERC stable isotope lab, SUERC. From December 2012 work on this project will be funded by a NERC grant (NE/H012842/1) to Prof. Damon Teagle.