Transient permeability in fault stepovers and rapid rates of orogenic gold deposit formation

Steven Micklethwaite, Arianne Ford, Walter Witt, Heather A Sheldon

Research output: Chapter in Book/Report/Conference proceedingChapter (Book)Researchpeer-review

3 Citations (Scopus)

Abstract

Stepovers exert a critical influence on crustal permeability and are known to control phenomena such as migration of hydrocarbons and location of geothermal fields. This chapter presents a systematic examination of the relationship between fault stepovers and ore deposits to provide insight into a primary control on permeability within continental crust at length scales of tens to thousands of kilometres, integrated over timescales of ore deposit formation. It considers accurate deposit-scale maps of stepovers associated with gold deposits from around the world to examine the geometry, aspect ratios and scaling properties of those stepovers. The chapter assess the influence of stepover geometries on the shear and normal stress changes that occur during earthquake or fault creep events and the implications these have for fracturing. It reviews and discusses the results of experiments in terms of transient enhancement of permeability through the Earth's crust and the profound implications they have for time-integrated fluid fluxes.

Original languageEnglish
Title of host publicationCrustal Permeability
EditorsTom Gleeson, Steven E. Ingebritsen
Place of PublicationChichester UK
PublisherJohn Wiley & Sons
Chapter20
Pages249-259
Number of pages11
Edition1
ISBN (Electronic)9781119166573
ISBN (Print)9781119166566
DOIs
Publication statusPublished - 31 Oct 2016
Externally publishedYes

Keywords

  • fluid flow
  • gold
  • permeability
  • scaling
  • static stress change
  • stepovers
  • time-integrated fluid flux

Cite this

Micklethwaite, S., Ford, A., Witt, W., & Sheldon, H. A. (2016). Transient permeability in fault stepovers and rapid rates of orogenic gold deposit formation. In T. Gleeson, & S. E. Ingebritsen (Eds.), Crustal Permeability (1 ed., pp. 249-259). John Wiley & Sons. https://doi.org/10.1002/9781119166573.ch20