Controls on primary porosity and permeability development in igneous rocks

Nick Petford*

*Corresponding author for this work

    Research output: Contribution to journalArticle

    19 Citations (Scopus)

    Abstract

    Some of the more important processes leading to the development of primary igneous porosity due to the cooling and crystallization of magma are reviewed. A distinction is made between volcanic and plutonic rocks, and crystalline and granular volcanic material. Porosity in each rock type is classified according to a proposed effective length scale and geometry into diffusive (Class D) and macroscopic flow (Class F) features. Estimated ranges in values of porosity and permeability are given for a wide selection of igneous rock types, and comparison is made with permeability variations (Δk) derived for both the continental and oceanic crust. While fracture porosity is dominant in most crystalline materials, primary porosity development may play an important role in the final (total) porosity in igneous basement. Some types of primary porosity and permeability in igneous rocks will be strongly time- and scale-dependent due to thermal effects associated with the emplacement and cooling of magmas and volcanic material. Tectonic reworking of the primary petrophysical properties of basement-forming igneous rocks may be significant in the development of regions of anisotropy and enhanced porosity.

    Original languageEnglish
    Pages (from-to)93-107
    Number of pages15
    JournalGeological Society Special Publication
    Volume214
    DOIs
    Publication statusPublished - 2003

    Fingerprint Dive into the research topics of 'Controls on primary porosity and permeability development in igneous rocks'. Together they form a unique fingerprint.

  • Cite this