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 Article
Compositional and petrogenetic features of schistose rocks of ibadan area, southwestern nigeria
TL;DR: Amphibole and quartz schist were studied in this paper with a view to elucidate their compositional characteristics and their evolution, and chemical analysis of the samples obtained by Inductively Coupled Plasma Mass Spectrometry (ICPMS) instrumentation method, involving major and trace elements reveal the silicieous nature of the quartz schists and and the amphibole.
Journal ArticleDOI
P–T evolution of the Pan-African Taba metamorphic belt, Sinai, Egypt: Constraints from metapelitic mineral assemblages
TL;DR: The Taba metamorphic belt (TMB) is one of four Pan-African metamorphics belts of the Sinai Peninsula forming the northernmost extension of the East African Orogen as mentioned in this paper, and the results support the interpretation that the Sinai basement formed at a magmatic arc during the collision between East and West Gondwana.
Journal ArticleDOI
Detrital zircon, detrital titanite and igneous clast U–Pb geochronology and basement–cover relationships of the Colonsay Group, SW Scotland: Laurentian provenance and correlation with the Neoproterozoic Dalradian Supergroup
Claire A. McAteer,J. Stephen Daly,Michael J. Flowerdew,James N. Connelly,James N. Connelly,Todd B. Housh,Martin J. Whitehouse +6 more
TL;DR: In this paper, a multidisciplinary provenance study, including in situ U-Pb dating of detrital titanite, was undertaken on the enigmatic low-grade metasediments of the Colonsay Group, SW Scotland to determine their source and assess previous correlations with major Neoproterozoic sedimentary sequences within the Scottish Caledonides.
Journal ArticleDOI
Detrital zircon U–Pb, Hf isotopes, detrital rutile and whole-rock geochemistry of the Huade Group on the northern margin of the North China Craton: Implications on the breakup of the Columbia supercontinent
TL;DR: In this article, the authors investigated the ages of detrital zircons from the Zhaertai-Bayan Obo-Huade rift zone on the northern margin of the North China Craton and found that the dominant 2690−2450-age population was likely sourced from the granitic rocks in the Yinshan Block and the subordinate 2150−1710-age populations were probably recycled from the metasedimentary units from the Khondalite Belt and/or derived from the similar aged granitic plutons of the Hongqiyingzi �
Journal ArticleDOI
Origin of the Ediacaran Porongos Group, Dom Feliciano Belt, southern Brazilian Shield, with emphasis on whole rock and detrital zircon geochemistry and U-Pb, Lu-Hf isotopes
TL;DR: The Porongos Group is the major component of a fold and thrust belt located in the central portion of the Dom Feliciano Belt in the Sul-Riograndense Shield, Brazil as discussed by the authors.
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