Geochemistry, petrology and origin of Neoproterozoic ironstones in the eastern part of the Adelaide Geosyncline, South Australia

Iron Formation: The Sedimentary Product of a Complex Interplay among Mantle, Tectonic, Oceanic, and Biospheric Processes

“…Neoproterozoic iron and manganese deposits are present in the (1) MacKenzie and Ogilvie Mountains of North America (see Figs. 1, 14; Young, 1976;Klein and Beukes, 1993a, b), (2) Urucum district of Brazil (Urban et al, 1992;Trompette et al, 1998;Klein and Ladeira, 2004), (3) Serrania de Mutun in Bolivia (Trompette et al, 1998), (4) southeastern Uruguay (Pecoits et al, 2008), (5) Damara orogen of Namibia (Breitkopf, 1988;Bühn et al, 1992), (6) Adelaide geosyncline of South Australia (Lottermoser and Ashley, 1999), (7) middle Tian-Shan in Kazakhstan, Kyrgyzstan (Zubtsov, 1972), (8) Malyi Khingan in the southern part of the Russian Far East, and (9) Erzin basin in Tuva, Russia, and in adjacent Mongolia (Ilyin, 2009).…”

“…A GIF and intraformational conglomerates containing hematite pebbles developed locally at the top of the Rapitan Iron Formation and in the Jacadigo Group, Brazil (Klein and Beukes, 1993a;Klein and Ladeira, 2004). The REE patterns for the Neoproterozoic iron formations have no or slightly positive Eu anomalies and no or slightly negative Ce anomalies (Fryer, 1976;Derry and Jacobsen, 1990;Klein and Beukes, 1993a;Lottermoser and Ashley, 1999;Klein and Ladeira, 2004;Liu et al, 2006), indicating a high degree of dilution of locally derived hydrothermal fluid by mildly oxidized seawater, within isolated to semi-isolated basins. Models that are generally accepted for Phanerozoic manganese deposits (e.g., Maynard, 2003) are, therefore, probably also applicable to the origin of Neoproterozoic iron formations.…”

Petrography and geochemistry of the Shilu Fe–Co–Cu ore district, South China: Implications for the origin of a Neoproterozoic BIF system

“…C PDB values (−5.5 to +0.9‰) for associated carbonates (Lottermoser and Ashley, 2000). It implies that hydrothermal exhalations added significant amounts of Fe and other metals to the then seawater, and that the Shilu BIFs of various facies were the result of chemical precipitation of dissolved Fe (and Co and Cu) during a postglacial, transgressive period and formed in a near-coastal environment under significant terrestrial influences (Lottermoser and Ashley, 2000).…”

Geological characteristics and age of the Dahongliutan Fe-ore deposit in the Western Kunlun orogenic belt, Xinjiang, northwestern China

“…Xu et al (2013Xu et al ( , 2014 Klein and Ladeira, 2004;Halverson et al, 2011) or glaciated rift environment (Young, 2002). Rapitantype BIFs have been widely reported to be related to the prominent Neoproterozoic glacial events (Sturian: 718-660 Ma; Marinoan: 651-635 Ma), such as those in the Rapitan in Canada, Urucum in Brazil, the Adelaide Geosyncline in South Australia, Damara in South Africa, southern Paraguay Belt in Brazil and Jiangnan paleocontinent in South China Block (Tang et al, 1987;Klein and Beukes, 1993;Lottermoser and Ashley, 2000;Klein and Ladeira, 2004;Ilyin, 2009;Babinski et al, 2013;Cox et al, 2013;Li et al, 2014).…”

“…On the other hand, the Dahongliutan BIF seems comparable to the Neoproterozoic Rapitan-type BIFs. For example, the Neoproterozoic (ca.750-700 Ma) BIFs in the eastern part of the Adelaide Geosyncline of South Australia comprises abundant Fe oxides (hematite, magnetite) and quartz, minor silicates (muscovite, chlorite, biotite, plagioclase, tourmaline), carbonate and apatite, and detrital mineral grains and lithic clasts, and was subjected to greenschist facies (biotite grade) metamorphism (Lottermoser and Ashley, 2000). However, the Dahongliutan BIF contains no evidence of contemporaneous glacimarine sedimentary rocks (e.g., tillites and diamictites).…”