Ree mobility and tetrad effects in bauxites an example from the Kanisheeteh deposit, NW Iran

Abstract

The Kanisheeteh bauxite deposit (NW Iran) is located on the Irano-Himalaya karst bauxite belt and was developed as stratiform horizon along the contact of the Permian and Triassic Formations. Based on absolute weathering index (AWI), HREE were leached out, whereas LREE suffered both leaching and fixation during bauxitization. The non-CHARAC characteristic of Y/Ho ratios can be attributed to geochemically known phenomenon as the "tetrad effect". The simultaneous convex and concave curves of the tetrad effect were observed in the chondritenormalized REE patterns of the bauxite ores. The correlation between the sizes of T 4 and AWI% values revealed two separate populations. The first one is characterized by a wide variation in sizes of T 4 and very narrow AWI% values, and is thought to be related to acidic zone of the profile. In contrast, the second one is marked by a narrow variation in sizes of T 4 and wide variation in AWI% values, and is conceived to be affiliated to alkaline zone of the profile. In this research, the tetrad effect proved to be capable of clarifying the geochemical characteristics of the deposit and can be applied as a good geochemical index to investigate the prevailed paleoconditions of depositional environments.

Iron Loss During Continental Weathering in the Early Carboniferous Period Recorded by Karst Bauxites

“…The Jiujialu Formation, which shows parallel unconformities with the overlying lower Carboniferous limestone/clay rock and the underlying Cambrian or Ordovician dolomite strata, usually comprises a 1–20 m thick bauxite bed (bauxite ore/clay rock) and an underlying 0–6 m thick iron bed (iron ore/iron‐rich clay) (Figure 2). This typical “iron‐bauxite” structure is widespread worldwide, such as the Ghiona bauxite deposit in Greece (Kalaitzidis et al., 2010), the Nurra bauxite deposit in Italy (Mameli et al., 2007), the Kanisheeteh, Kanirash, Shahindezh, Qopi, Darzi‐Vali; Soleiman‐Kandi, Kani‐Zarrineh bauxite deposits in Iran (Abedini, Habibi Mehr, et al., 2019; Abedini et al., 2019a, 2019b; Abedini et al., 2022a, 2022b; Calagari & Abedini, 2007; Khosravi et al., 2017, 2021), and most bauxite deposits in China (e.g., Ling et al., 2017; X. Liu et al., 2017; Yu et al., 2019; Z. Zhang et al., 2013). In central Guizhou, the thickness of the Jiujialu Formation is controlled by the paleo‐karst unconformities, that is, the thickness above the karst depression is greater than that above the highland (Figure 3).…”

Provenance and Tectonic Evolution of Bauxite Deposits in the Tethys: Perspective From Random Forest and Logistic Regression Analyses

“…This suggests that climate may not be a key factor affecting the TiO 2 content (Figure 5b). Some bauxite deposits formed between 30° and 40° latitude, such as Amir‐Abad, Kani Zarrineh, Sahindezh, Kanisheeteh, Soleiman Kandi bauxites in northwestern Iran (Abedini & Khosravi, 2020; Abedini, Mongelli, & Khosravi, 2022; Abedini et al., 2019a, 2019b, 2021) and Siahrudbar bauxite in Alborz mountains, Iran (Kiaeshkevarian et al., 2020), Languedoc and Provence bauxite in southern France (Mondillo et al., 2019). This is mainly due to greenhouse conditions in the Mesozoic.…”

Formation of Ti-rich bauxite from alkali basalt in continental margin carbonates, Payas region, SE Turkey: implications for sea level change in the Upper Cretaceous

“…As a general feature, the average content of MgO + CaO + Na 2 O + K 2 O in bauxite is 0.52 wt%, and these values are similar to other bauxites in Turkey and the rest of the world (Hanilçi, 2019). However, the average TiO 2 value of the Payas region bauxite is 9.67 wt%, and a bauxite deposit with such a high TiO 2 value was reported only in Iran (Abedini et al, 2019).…”