The Alteration of Ilmenite in Metasediments: The Implication of Metamorphism
Abstract
The alteration of ilmenite is well-known in non-consolidated sediments. Unfortunately, no specific study has been realized on Ti-rich metasediments. The Sutton area provides a voluminous amount of Fe-Ti minerals that reached greenschist metamorphic facies and it is probably the best place to study its implication in the ilmenite alteration process. The challenge in studying those metamorphic placers is to discriminate which events produced each alteration. In other words, what is the effect of pre- and post-depositional weathering, the effect of diagenesis and metamorphism on the alteration of ilmenite. A detailed ore-microscopic investigation revealed that the implication of metamorphism on the alteration of ilmenite is significant. In fact, metamorphic fluids transformed fresh ilmenite into an almost pure TiO2 phase. Furthermore, the distribution of the alteration is very heterogeneous and it mainly depends on the primary porosity and permeability of the ilmenite-bearing rock. So, in this case, the metamorphism enriched the Ti minerals by leaching non-economic elements, like iron.
- Publication:
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AGU Spring Meeting Abstracts
- Pub Date:
- May 2004
- Bibcode:
- 2004AGUSM.V21B..06H
- Keywords:
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- 3660 Metamorphic petrology;
- 3665 Mineral occurrences and deposits;
- 3675 Sedimentary petrology;
- 8045 Role of fluids