PhD projects: The Nature of Magmatic Carbon on Mars

University of St Andrews

PhD Fixed Term St Andrews, UK

Uploaded 25 May 2019

Job Description

Differentiating between the possible source(s) for biologically-significant carbonaceous compounds in the Martian lithosphere and atmosphere is not straightforward because the chemistry of a planet’s atmosphere is an archive of surface and subsurface processes, inclusive of volcanism, weathering, meteoritic influx, and biological processes. For example, methane (CH4) has been observed in the Martian atmosphere, but the origin(s) of these emissions are enigmatic. Recent insights show that sedimentary rocks on Mars can store reduced organic carbon on billion-year timescales (Eigenbrode et al., 2018), and the source domain for Martian basalts are known to contain both solid macro-molecular carbon and gaseous organic carbon components (CH4; Blamey et al., 2015). Importantly, macro-molecular carbon co-occurs in association with high-temperature magmatic minerals, and this requires that they are sourced directly from the Martian interior (Steele et al., 2012). Ergo, a reduced carbon component present during Martian magmatism could be a primary source of recently observed CH4 in the Martian atmosphere (Webster et al., 2018). Addressing this possibility is fundamental to the ExoMars programme, and establishes the focus of this fully-funded PhD project.

The main aim of this PhD studentship is to test the hypothesis that gaseous methane in the Martian atmosphere and solid macro-molecular carbon in Martian basalts can be the product of Martian magmatism. To achieve this, we will address three key objectives: 

[1] What carbonaceous gases does magmatism release into the Martian atmosphere? 

[2] Is macro-molecular carbon in Martian basalts the result of Martian magmatism or secondary alteration in the Martian lithosphere? 

[3] What is the equilibrium carbon isotope value of magmatic carbon on Mars?

Person Specification

Research applicants within the Faculty of Science require a good first degree with Honours at 2.1 (UK) or the overseas equivalent.