6533b7d0fe1ef96bd125b755
RESEARCH PRODUCT
Chemical variations in clay minerals of the Archaean Barberton Greenstone Belt (South Africa)
Theofilos ToulkeridisTheofilos ToulkeridisAlfred Kr:onerNorbert Clauersubject
Recrystallization (geology)FelsicLithologyGeochemistryGeologyGreenstone beltengineering.materialGeochemistry and PetrologyIlliteengineeringSedimentary rockMaficPetrologyClay mineralsGeologydescription
Abstract Four rock profiles of shales, carbonates and greywacke-type sediments were sampled from the mafic compositional influenced sedimentary Fig Tree Group and from overlying, more felsic related, sedimentary Moodies Group of the Archaean Barberton Greenstone Belt in South Africa. Clay separates of forty sedimentary rocks were examined by XRD and SEM to study the mineralogical, chemical and morphological variations of the constitutive illite and chlorite. The clay minerals showed a significant K-enrichment in the illites and Mg- and Fe-depletions in the chlorites upwards the stratigraphic sequence. Three independent parameters influenced these variations: (1) a change in the origin of the source rocks; (2) the host-rock lithologies; and (3) a tectono-thermal recrystallization process.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1996-09-01 | Precambrian Research |