Evaluation of different models for the origin of the Siberian Traps

Abstract

Various evidence, including size and volume of the Siberian Traps, timing and duration of eruptions, paleotectonic and paleogeographic reconstructions, lithospheric structure, heat flow, trace element and radiogenic isotope compositions of lava are reviewed in this chapter.The major evidence may be summarized as follows. The Siberian Traps erupted in a number of brief volcanic events from the Late Permian until the end of the Middle Triassic. They In radiogenic isotope and trace element coordinates, mixing trends between these two types of magma are absent or, at least, not evident. Some volcanic rocks contain primary magmatic mica. These are considered in light of different models. Each model can explain, or was thought to explain, particular observations. However, some evidence can be fatal for some models. For example, the enormous size and volume cannot be explained in the framework of impact and edge-driven convection models, and is problematic for lithospheric delamination models. Plume models face problems explaining the uplift/subsidence pattern and the absence of mixing curves between expected high-Ti primary plume melts and contaminated low-Ti

Petrogenises of Triassic gabbroic and basaltic rocks from Chukotka, NE Russia: Eastern end of the ‘arc–type’ Siberian LIP?

“…As is common in many large igneous provinces, the Siberian LIP lavas include both high and low-Ti compositional types (Sharma et al, 1991;Fedorenko and Czamanske, 1997). The most important characteristics of the dominant low-Ti lavas are their IAB-type trace element patterns (Ivanov 2007), whereas those of the high-Ti lavas (such as meimechites) display OIBtype composition (Arndt et al, 1998). The high-Ti basalts display chemical characteristics of deeper-derived melts controlled by garnet which has been attributed to the direct involvement of a mantle plume (Lightfoot et al, 1993;Wooden et al, 1993).…”

“…The source of arc-like LIP magma is interpreted to be an enriched mantle that sourced previous arc and back-arc magmatism (e.g., Puffer, 2001). Recently, Ivanov (2007) pointed out that the IAB-like geochemical signature of the majority of the low-Ti laves is attributed to the wet magma source. Moreover, Ivanov et al (2008) and Ivanov and Litasov (2014) discussed the similarity of the calculated initial melt compositions of the southeastern Siberian flood basalt province (Angara-Taseevskaya dolerite sills) with the initial melt compositions of the modern arc of Eastern Kamchatka (Portnyagin et al, 2007) in terms of trace elements, suggesting a similar subduction-related processes are responsible for their origin.…”

“…Hydrous nature. The presence of hydrous minerals is reported from several localities of Siberian LIP: amphibole and biotite in Noril'sk I intrusion (Renne 1995), biotite in meimechite from Maymecha-Kotuy region (Fedorenko and Czamanske 1997); biotite in the olivine gabbro from west Siberian basin (Reichow et al, 2002); biotite in dolerite sills of Angara-Taseevskaya (Ivanov 2007); amphibole and biotite in the dolerite of New Siberian Islands (Kuz'michev and Pease 2007). However, it is important to note that amphibole is rarely a phenocryst in arc basalts (Davidson et al, 2007) and their scarcity can be attributed to its instability at low pressures (e.g., Rutherford and Devine, 1988;Romick et al, 1992).…”

“…Siberian LIP is one of the most voluminous (~4 × 10 6 km 3 ; Ivanov, 2007) and the representative examples of IABtype LIPs, because of the majority of the erupted low-Ti basalts are characterized by IAB-type trace element pat-terns (Puffer, 2001;Ivanov, 2007). The high-Ti series rocks (e.g., meimechites; Arndt et al, 1998;Sobolev et al, 2009) are volumetrically insignificant and commonly display OIB-type geochemical features.…”

“…The IAB-type geochemical feature of the low-Ti basalts of Siberian LIP are traditionally attributed to a fingerprint of lithospheric contamination (Lightfoot et al, 1993;Reichow et al, 2005). However, the presence of strong arc-type geochemical signatures and primary magmatic waterbearing minerals in the low-Ti series rocks of Siberian LIP (Reichow et al, 2002;Ivanov 2007) indicate that contamination of lithospheric mantle cannot be the controlling factor. Therefore, the dominant IAB-type, low-Ti basalts within the Siberian LIP have been attributed to wet mantle upwelling, driven by dehydration of the Mongolia-Okhotsk oceanic slab at the mantle transition zone (Ivanov and Litasov, 2014).…”