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Bohrmann et al. 1989 advanced the idea that the silicate phase from some clinoptilolites come from the diagenetic degradation of biogenic opal (from radiolarians in that case but presumably also other siliceous microfossils).

If this hypothesis is still regarded as valid, is clinoptilolite the only kind of authigenic zeolite that can be traced to biogenic opal?

Has any work been done in that domain since this paper?

Source:
Bohrmann, G., Stein, R., Faugères, J.-C., 1989. Authigenic zeolites and their relation to silica diagenesis in ODP Site 661 sediments (Leg 108, Eastern Equatorial Atlantic). Geologische Rundschau, 78(3): 779-792.

plannapus
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  • Did you look at the citing papers? Looking at some of the paper titles, looks like there was more recent research. – Gimelist Nov 07 '14 at 17:34

1 Answers1

2

Yes, there have been recent research in this field.

In the article Oceanic minerals: Their origin, nature of their environment, and significance (Kastner, 1999), who asserts that

The zeolites phillipsite and analcime mostly reflect on diagenesis of volcanic matter; clinoptilote and heulandite occur in Si-rich diagenetic environments.

and confirm that

In addition to diagenetic opal-CT and quartz that form from the dissolution of biogenic opal-A, other common authigenic alumino-silicate minerals are smectites and zeolites.

This is further confirmed by a 2007 paper Clinoptilolite as a new proxy of enhanced biogenic silica productivity in lower Miocene carbonate sediments of the Bahamas platform: Isotopic and thermodynamic evidence (Karpoff et al) which determined that

Seawater–rock modeling specifies that clinoptilolite precipitates from the dissolution of biogenic silica, which reacts with clay minerals. The amount of silica (opal-A) involved in the reaction has to be significant enough, at least 10 wt.%, to account for the observed content of clinoptilolite occurring at the most zeolite-rich level. Modeling also shows that the observed amount of clinoptilolite (∼ 19%) reflects an in situ and short-term reaction due to the high reactivity of primary biogenic silica (opal-A) until its complete depletion.