Geochemistry of ∼1.9 Ga sedimentary rocks from northeastern Labrador, Canada

Geochemistry of Fluvial Sediments from Geregu, Southwest Nigeria

“…The understanding that Al 2 O 3 /TiO 2 ratios in shales are similar to those of the parent rocks is a major support for their use as source rock indicators, e.g. the study by Hayashi et al [32]. Previous workers have suggested that sediments characterised by an Al 2 O 3 /TiO 2 ratio <14 have a mafic igneous protolith, and sediments associated with Al 2 O 3 /TiO 2 ratios that vary from 19 to 28 are inferred to have a felsic igneous rock source [33].…”

“…Previous workers have suggested that sediments characterised by an Al 2 O 3 /TiO 2 ratio <14 have a mafic igneous protolith, and sediments associated with Al 2 O 3 /TiO 2 ratios that vary from 19 to 28 are inferred to have a felsic igneous rock source [33]. Similarly, Hayashi et al [32] have used high Al 2 O 3 /TiO 2 ratios (>21) to suggest a felsic protolith source for the sedimentary rocks from northeastern Labrador, Canada. Accordingly, the units of the studied stratigraphic sequence have a predominantly felsic or felsic-to-intermediate igneous rock source.…”

Siliciclastic input into upper Cenomanian synorogenic sediments of the High-Tatric Unit, Central Western Carpathians (Tatra Mountains); petrography, geochemistry and provenance

“…The Al 2 O 3 /TiO 2 ra tio ranges from 16.1 to 22.7 in the sam ples, the val ues typ i cal of in ter me di ate and fel sic rocks (Hayashi et al, 1997). This prov e nance is con firmed by a low amount of TiO 2 (0.44 wt.% on av er age; Ap pen dix 1), lower than in the PAAS (Tay lor and McLennan, 1985) that is char ac ter is tic of more evolved (fel sic) rocks.…”

Geochemical Discriminant for Provenance Characterization and Palaeogeography of Shales from Dahomey Embayment, Southwestern Nigeria

“…Following this approach by [32] shale samples of the Gbekebo-1 well plot in the mafic and Quartzose sedimentary fields, implying a mixed source area ( Figure 5(a)). The ratio of Al 2 O 3 /TiO 2 in shales has been suggested to be similar to that of the source rock [33] as such it is used as an index of provenance. Hayashi et al [33] [34] proposed a plot of La/Th against Hf to discriminate provenance; and in this study the samples plotted in felsic to mixed felsic/basic sources ( Figure 5(b)).…”