Petrifaction of wood by silica minerals
Abstract
Seventy-five woods of Australian origin have been examined by means of X-ray diffraction, optical and scanning electron microscopy, and differential thermal analysis. The silica is in one or other of the following forms: opal-A, opal-CT, chalcedony, quartz, quartz + chalcedony, opal + chalcedony. More than half of them consist of opal-CT or chalcedony. The results indicate that petrifaction by silica involves penetration of the wood via splits or checks, permeation of cell walls via a reticulated system of micropores, enlargement of the micropore system as cell wall components break down, and continuing deposition of silica ata rate and in a manner consistent with maintaining the dimensional stability of the wood. Deposition of silica in cell lumina and intercellular voids may be sometimes, but not always, a separate and later event. The final stages of lithification involve loss of water and perhaps transformation of one form of silica into another.
- Publication:
-
Sedimentary Geology
- Pub Date:
- May 1984
- DOI:
- 10.1016/0037-0738(84)90048-4
- Bibcode:
- 1984SedG...39..149S