Journal ArticleDOI
Geochemical classification of terrigenous sands and shales from core or log data
Reads0
Chats0
TLDR
In this article, a means of relating geochemical concentrations to existing sandstone classification schemes is proposed based on three chemical parameters: the SiO2/Al2O3 ratio, the Fe 2O3/K2O ratio, and the Ca content.Abstract:
A means of relating geochemical concentrations to existing sandstone classification schemes is based on three chemical parameters: the SiO2/Al2O3 ratio, the Fe2O3/K2O ratio, and the Ca content. In terrigenous sands and shales, the SiO2/Al2O3 ratio separates Si-rich quartzarenites from Al-rich shales, with other sand types showing intermediate values. The ratio of total iron (as Fe2O3) to K2O separates lithic sands (litharenites and sublitharenites) from feldspathic sands (arkoses and subarkoses). In addition, very high Fe2O3/K2O ratios indicate Fe-rich shales (e.g., pyritic, sideritic, hematitic) or Fe-rich sands (e.g., gl uconitic) depending on the silica/alumina ratio. The Ca content is used to differentiate noncalcareous from calcareous sandstones and shales and to separate siliciclastic from carbonate rocks. Sandstones are classified the same by this scheme as by petrographic analysis about 84% of the time, and shales are effectively discriminated from sandstones. The requisite input data can be accurately supplied by geochemical well-logging measurements, enabling unbiased sandstone classification to be displayed on a continuous basis with depth.read more
Citations
More filters
Journal ArticleDOI
The Egéré Paleo-Mesoproterozoic rifted passive margin of the LATEA metacraton (Central Hoggar, Tuareg Shield, Algeria) subducted and exhumed during the Pan-African orogeny: U-Pb zircon ages, P-T-t paths, geochemistry and Sr-Nd isotopes
Khadidja Ouzegane,Jean-Paul Liégeois,Sid Ali Doukkari,Jean-Robert Kienast,Amar Arab,Amar Drareni,Andreas Gärtner,Ulf Linnemann +7 more
TL;DR: In this article , the authors show that the Arechchoum Group is an alkaline silicic large igneous province of early Rhyacian age (c. 2.28 Ga) underlain by the Archean Amadror craton, defined here.
Journal ArticleDOI
U-Pb ages on detrital zircons and geochemistry of Lula paragneiss from Variscan belt, NE Sardinia, Italy: implications for source rocks and early Paleozoic paleogeography
TL;DR: In this article, chemical analyses of garnet-bearing metasediments and EMP and U/Pb analyses of detrital zircons of the Lula paragneisses in the Axial Zone of the Variscan belt (NE Sardinia) give significant contribution to the reconstruction of the early Paleozoic evolution of the northern Gondwana margin.
Journal ArticleDOI
Mesozoic sandstones and the reconstruction of tectonic depositional environments in the Bureya sedimentary basin in the Far East
TL;DR: The early Jurassic-Early Cretaceous tectonic environments were reconstructed for the first time on the basis of the study of sandstones from the Soloni-Urgal interfluve (Bureya sedimentary basin, Far East) as mentioned in this paper.
Dissertation
The Petrography and Geochemistry of the Kadinhani Area, Central Turkey
TL;DR: In this paper, the authors investigated the Kadinhani metamorphic, igneous and sedimentary rocks in Iran and found that the area was metamorphosed first under the conditions of the greenschist facies (the most important minerals, muscovite, chlorite and chloritoid, actinolite and stilpnomelane) and then later under the blueschistfacies metamorphism which gave rise to magnesio riebeckite, crossite, glaucophane, phengite and albite minerals.
Related Papers (5)
Early Proterozoic climates and plate motions inferred from major element chemistry of lutites
H.W. Nesbitt,Grant M. Young +1 more
Trace element characteristics of graywackes and tectonic setting discrimination of sedimentary basins
Mukul R. Bhatia,Keith A.W. Crook +1 more