A petrogenetic study of anorogenic felsic magmatism in the Cretaceous Paresis ring complex, Namibia: evidence for mixing of crust and mantle-derived components

An Early Permian (ca. 280Ma) silicic igneous province in the Alxa Block, NW China: A magmatic flare-up triggered by a mantle-plume?

“…The origins of A-type granites have been attributed to: (1) direct fractionation of mantle-derived alkaline basalts (e.g., Mushkin et al, 2003;Turner and Rushmer, 2009;Turner et al, 1992); (2) partial melting of crustal materials at high temperature (e.g., Collins et al, 1982;King et al, 1997;Wang et al, 2010a) and (3) hybridization between anatectic crust-derived felsic and mantle-derived mafic magmas (e.g., Kerr and Fryer, 1993;Mingram et al, 2000;Yang et al, 2006). The absence of any mafic microgranular enclaves in the A-type pluton does not support the generation of these A-type granites by mixing of mantle-derived mafic magma and crustal-derived silicic melts.…”

Geochemistry of the Early Cretaceous Koegel Fontein Anorogenic Igneous Complex, South Africa

“…In Namibia there is a consistent observation is that the mafic alkaline intrusions are younger than the tholeiitic units. This is the case for Okenyenya (Martinez et al, 1996), Messum (Korn and Martin, 1954;Harris et al, 1999), Paresis (Siedner, 1965;Mingram et al, 2000), and…”

“…Petrogenetic studies of several Damaraland complexes have shown the highly proportion of mantlederived magmas in the granitic units (Schmitt et al, 2000;Mingram et al, 2000;Frindt et al, 2004). Trumbull et al (2004) showed that the Nd and oxygen isotopic compositions from these complexes can be explained at first order by a two-component mixing of crustal and mantle sources.…”

Implications from zircon-saturation temperatures and lithological assemblages for Early Permian thermal anomaly in northwest China

“…2), which is ascribed to the result of crust-mantle plume interaction (Etendeka: Ewart et al, 1998;Frindt et al, 2004;Harris et al, 1999;Mingram et al, 2000;Schmitt et al, 2000;Trumbull et al, 2004;Emeishan LIP: Zhong et al, 2007Shellnutt et al, 2011;Shellnutt and Jahn, 2010;Xu et al, 2010). Etendeka granitoids have zircon saturation temperatures ranging from 803°C to 926°C with an average significantly greater than 800°C (Fig.…”

“…2). The high ε Nd (t) values and young T DM ages may be indicative of growth of juvenile crust by plume-related magmatism (Mingram et al, 2000;Schmitt et al, 2000;Trumbull et al, 2004;Xu et al, 2008;Zhong et al, 2011). In addition to the ubiquitous involvement of juvenile crust in the genesis of granitoids in LIPs, the participation of ancient crust in magma genesis is also evident as attested by lower ε Nd (t) values associated in the Etendeka and Emeishan provinces (Bryan, 2007;and references therein).…”