Mineral, chemical and isotope compositions of clay subfractions from formations of the Srednii Peninsula, Murmansk coast of the Barents Sea

DOI

Fine-grained clay subfractions (SFs) with particle size of <0.1, 0.1-0.2, 0.2-0.3, 0.3-0.6, 0.6-2.0, and 2-5 µm separated from claystone of Upper Precambrian Pumanskaya and Poropelonskaya formations on the Srednii Peninsula were studied by transmission electron microscopy, X-ray diffraction, and Rb-Sr methods. All subfractions consist of low-temperature illite and chlorite, and contribution of chlorite decreases with diminishing particle size. The crystallinity index and I002/I001 ratio increase from coarse- to fine-grained SFs. Leaching by ammonium acetate solution and Rb-Sr systematics in combination with mineralogical and morphological data indicate that illite in Upper Proterozoic claystone from the Srednii Peninsula formed during three time intervals: 810-830, 610-620, and about 570 Ma ago. The first generation of this mineral with low Rb/Sr ratio dominates in coarse-grained SFs while the second and third generations with a high Rb/Sr ratio prevail in fine-grained SFs. All of three generations are known in Poropelon claystone, whereas Puman claystone contains only illite of the first and second generations. Geological processes responsible for multistage illite evolution in claystones are discussed.

Supplement to: Gorokhov, I M; Mel'nikov, N N; Negrutsa, V Z; Turchenko, T L; Kutyavin, E P (2002): The Multistage Illite Evolution in Upper Proterozoic Claystones from the Srednii Peninsula, Murmansk Coast of the Barents Sea. Lithology and Mineral Resources, 37(2), 162-179

Identifier
DOI https://doi.org/10.1594/PANGAEA.785311
Related Identifier https://doi.org/10.1023/A:1014828617929
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.785311
Provenance
Creator Gorokhov, I M; Mel'nikov, N N; Negrutsa, V Z; Turchenko, T L; Kutyavin, E P
Publisher PANGAEA
Publication Year 2002
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 2 datasets
Discipline Earth System Research
Spatial Coverage (31.840W, 69.716S, 32.083E, 69.815N); Srednii Peninsula, Murmansk Coast