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UCC and PAAS Normalized Trace element patterns of Triassic sandstones and shales from the Spiti region, Tethys Himalaya (UCC values after McLennan, 2001; PAAS values after Taylor and McLennan, 1985).
Source publication
The Spiti region, renowned as the Museum of Indian Geology, is a world-famous sedimentary succession containing well-exposed sequences from Neoproterozoic to Cretaceous age. In this study, Triassic siliciclastic sedi-mentary rocks of the Lilang Supergroup were chosen to understand weathering history, provenance, paleoclimate, and depositional condi...
Contexts in source publication
Context 1
... of mafic content as biotite in the samples. The high depletion of Na 2 O is due to its high solubility nature compared to other oxides. The low concentration of TiO 2 (0.32 wt %) and P 2 O 5 (0.08 wt %) is attributed to the negligible amount of ilmenite and full removal of the phosphatic phase during the weathering process. Compared to UCC (Fig. 6b), the trace elements in sandstone show a similar trend as that of UCC, whereas some elements depict enrichment and depletion trends in the diagram. The enrichment for Zr suggests zircon enrichment in the sandstones, corresponding to the recycling nature of samples. Co, Ni, and Cr show enrichment indicating a minor amount of mafic ...
Context 2
... SiO 2 , Al 2 O 3, and TiO 2 show neither enrichment nor depletion compared to PAAS, while CaO and MgO are enriched, likely is due to fossil contents or calcite and dolomite. MnO, TiO 2, and P 2 O 5 are depleted due to the absence of minerals containing Mn, Ti, and P. The trace elements in most of the shales show depletion when compared with PAAS (Fig. 6a). Rb, Sr, Ba, Ni, Co, and Sc are all depleted relative to PAAS. Zr and Hf also show depletion, but with wide variation across the PAAS trends. The lower concentration of trace elements can be attributed to the low values of trace elements in the parent rocks or plagioclase and K-feldspar, which are the storehouses of strontium and ...
Citations
... In addition, Zn abundances (> 56 ppm) indicate a contribution from chalcophile minerals (Fig. 5). Scatter distribution suggests varying populations of lithic fragments in the sandstones and fine-grained sediments (Ganai et al. 2023;Rashid et al. 2023). ...
... Accordingly, Ca, Na, and Sr can preferentially be lost during intensive weathering, whereas immobile elements such as Al and Ti are retained (Condie 1993;Nyakairu and Koeberl 2001;Ahmad et al. 2022). The PIA (Eq. 3) in (A-K)-C-N space (Fedo et al. 1995) can also be used to distinguish weathering, diagenesis of (Table 1), suggesting that the plagioclase has been completely converted to secondary aluminous clay minerals (Fedo et al. 1995;Ahmad and Chandra 2013;Ganai et al. 2023). The PIA value of fresh rocks is about 50 (Fedo et al. 1995). ...
... Trace elements, particularly immobile elements like Cr, Ni, Co, Zr, and V, are valuable markers for Taylor and McLennan (1985) provenance investigations due to their deficient mobility during the sedimentary process (Mclennan et al. 1993;Cox et al. 1995;Cai et al. 2008;Overare et al. 2020;Ganai et al. 2023;Rashid et al. 2023). In this study, all samples indicate high Cr (avg. ...
The Andigama Basin is a pre-rift Gondwana sedimentary basin containing Late Jurassic to Early Cretaceous calcareous sandstones and carbonaceous shales of varying thickness. This study aims to reconstruct the weathering, tectonic setting, and paleoenvironment of East Gondwanaland using a 90 m deep drill core. Whole-rock geochemistry and elemental analysis were carried out using X-ray fluorescence spectrometry and CHNS/O elemental analyzer, respectively. Lithological changes in the borehole core reflect diverse hydrodynamic conditions. X-ray diffraction patterns indicate a significantly high content of quartz and kaolinite peaks. Scanning electron microscope images suggest that quartz, carbonate, and aluminosilicate dominant detrital particles and chemical residues enhanced the cementation by reducing the porosity and permeability of sealing interfaces. Major oxide and trace element concentrations are approximately similar to the Upper Continental Crust values. High Chemical Index of Alteration, Plagioclase Index of Alteration, Index of Compositional Variability, and high content of kaolinite peaks reflect intense chemical weathering, suggesting a hot and humid climate during the Late Jurassic–Early Cretaceous periods. The calculated paleo-land surface temperature (24.7 ± 5 °C) and mean annual precipitation (1120 mm) values are also consistent with the interpretation of weathering indices and global oxygen isotopic studies. Provenance and tectonic setting discrimination diagrams suggest the deposition of quartzose and mafic igneous sources under the passive margin stage. In addition, elemental analysis indicates a nutrient-rich (average total organic carbon = 4.67 ± 1.04 wt. % and total nitrogen = 3.13 ± 3.39 wt. %) and oxic to oxygen-poor reducing (average total sulfur = 2.13 ± 1.43 wt. %) swamp environment. Consequently, the Late Jurassic–Early Cretaceous climate was simulated as a prominent deglaciation/hot and humid climate in the Gondwana supercontinent, based on calculated paleo-land surface temperatures and mean annual precipitation.
... According to Ganai et al. (2023), the weathering indices of the Triassic siliciclastic rocks of the Lilang Supergroup and the Spiti Formation in the Spiti region show a modest to a high degree of chemical weathering. A drop in CIA and other weathering indices indicate variations in the climate and environment throughout sediment deposition. ...
82 publications by Indian geoscientists pertaining to the Proterozoic–Phanerozoic have come out during the last four years (2020–2024). Guide Books for the IGC 2020, GSI publication on the Precambrian sequences and a publication on the evolution of the Lesser Himalaya provide glimpses of regional geology. Other publications deal with geochemistry, sedimentology, isotope geology, palaeontology, and stratigraphy. A succinct summary of the publications is presented with short comments where necessary.
... According to Ganai et al. (2023), rock fragments will indicate the provenance of the sediment 2) Schist fragment, was found in 2 sandstone samples ST9-BTP-PTR and ST8-BTP-PTR. ...
The Walanae Formation has a wide distribution in the southern arm of Sulawesi, this rock formation was deposited during the formation of the basin due to the Walanae strike-slip fault. The Walanae Formation in the study area comprises sedimentary rocks and pyroclastic rocks, which give different soil characteristics. This study aims to determine the types of sandstones, rocks of origin, and provenance of sandstones in the study area by using spot sampling at representative stations and petrographic analysis. The sandstones of the study area are divided into two groups based on Folk (1974), namely arkose lithic and feldspathic litharenite. Based on the type of quartz, rock fragments, and associated minerals, the origin of the sandstones in the study area are plutonic igneous rocks, volcanic rocks, sedimentary rocks, and metamorphic rocks. The results show that the types of provenance sandstones in the study area are magmatic arc and recycled orogenic.
