Origin of the martian dichotomy and Tharsis from a giant impact causing massive magmatism

Dynamics and Thermal History of the Terrestrial Planets, the Moon, and Io

“…More recently, the thermochemical evolution of terrestrial planets, in particular for Mars, has been also calculated with 2-D and 3-D convection models (e.g., Golabek et al, 2011;Keller and Tackley, 2009;Nakagawa and Tackley, 2012;Ogawa and Yanagisawa, 2011;Ruedas et al, 2013a,b). These models do not require parameterizing the crustal growth with the convective vigor but instead calculating self-consistently the melt production and associated processes like depletion of heat sources and volatiles in the residual mantle whenever the local temperature exceeds the solidus temperature.…”

“…This idea has recently been revived in a series of articles explaining the observed elliptical shape of the lowlands (Andrews-Hanna et al, 2008;Marinova et al, 2008;Nimmo et al, 2008). For an endogenic origin of the dichotomy, four different mechanisms have been proposed that are associated with (1) the evolution of an early magma ocean (Elkins-Tanton et al, 2003;Hess and Parmentier, 2001), (2) an episode of degree-one mantle convection (Ke and Solomatov, 2006;Keller and Tackley, 2009;Schubert and Lingenfelter, 1973;Wise et al, 1979;Zhong and Zuber, 2001), (3) a thermal anomaly following a giant impact in the southern hemisphere (Golabek et al, 2011;Reese and Solomatov, 2006;Reese et al, 2010), and (4) an early phase of plate tectonics (Sleep, 1994). For an endogenic origin of the dichotomy, four different mechanisms have been proposed that are associated with (1) the evolution of an early magma ocean (Elkins-Tanton et al, 2003;Hess and Parmentier, 2001), (2) an episode of degree-one mantle convection (Ke and Solomatov, 2006;Keller and Tackley, 2009;Schubert and Lingenfelter, 1973;Wise et al, 1979;Zhong and Zuber, 2001), (3) a thermal anomaly following a giant impact in the southern hemisphere (Golabek et al, 2011;Reese and Solomatov, 2006;Reese et al, 2010), and (4) an early phase of plate tectonics (Sleep, 1994).…”

The effects of mantle composition on the peridotite solidus: Implications for the magmatic history of Mars

“…Studies of magma production and the thermal evolution of Mars commonly have assumed that the martian mantle can be modeled using a terrestrial peridotite solidus (e.g., Hauck and Phillips, 2002;Spohn, 2003, 2006;Redmond and King, 2004;Schumacher and Breuer, 2006;Fraeman and Korenaga, 2010;Ghods and ArkaniHamed, 2011;Golabek et al, 2011;Morschhauser et al, 2011). The assumption that Mars has an Earth-like solidus is typically made for convenience, because the terrestrial mantle composition is better constrained and its melting relationships are better studied.…”

“…The assumption that Mars has an Earth-like solidus is typically made for convenience, because the terrestrial mantle composition is better constrained and its melting relationships are better studied. Some of these investigators did recognize that that the martian mantle has a lower Mg# than Earth but used a terrestrial solidus because Mg# alone does not adequately capture the variability of the solidus temperature with composition (Hauck and Phillips, 2002;Golabek et al, 2011). Bertka and Holloway (1994), Draper et al (2003), and Agee and Draper (2004) performed experimental melting studies of candidate Mars mantle compositions, and several studies have used those results to constrain magma production in martian mantle plume and thermal evolution models (Kiefer, 2003;Li and Kiefer, 2007;O'Neill et al, 2007;Sandu and Kiefer, 2012;Š rámek and Zhong, 2012;Ruedas et al, 2013;Sekhar and King, 2014).…”

An episodic slab-rollback model for the origin of the Tharsis rise on Mars: Implications for initiation of local plate subduction and final unification of a kinematically linked global plate-tectonic network on Earth

“…1). Although understanding of this large topographic feature, occupying 25% of the Martian surface, has been the focal point of several excellent syntheses (Zuber, 2001;Phillips et al, 2001;Solomon et al, 2005;Nimmo and Tanaka, 2005;Carr and Head, 2010;Golombek and Phillips, 2010), its tectonic origin remains debated. Existing models involve construction of the highland either from below (magmatic underplating-induced hotspot activity or mantle upwelling; Carr, 1974;Wise et al, 1979;Masson, 1996a, 1996b;Harder and Christensen, 1996;Baker et al, 2007;Dohm et al, 2007;Zhong, 2009) or from above (voluminous volcanic deposits induced by impacts or some forms of lithospheric deformation as inducers; Solomon and Head, 1982;Sleep, 1994;Stevenson, 2001;Reese et al, 2004;Golabek et al, 2011).…”