The direction of magma flow and behaviour of the magma in the formation of the Ferrar Large Igneous Province 180 million years ago, Pandora Spyre and Terra Cotta Mountain, Victoria Land

Exposed at Terra Cotta Mountain and Pandora Spyre are vertical bladelike bodies of basaltic rock which cut across older pale colored sedimentary rocks. The pathway the magma took to the earth's surface when it erupted and the behaviour of rising basaltic magma as it advanced towards the surface was investigated. Field observations of dyke texture, vesicularity, crystal population and lithic fragment content, dyke contacts with the country rock and joint patterns within the dykes, field measurements of veins, joints and fractures in country rock next to the dykes and sills was all investigated. Numerous rock samples were analysed by anisotropic magnetic susceptibility (AMS) to determine magma flow direction. A petrological study to determine mineralogy and degree of glassiness (which is a good indicator of magma fluidity) was carried out and a geochemical study of collected rock samples at Pandora Spyre and Terra Cotta Mountain was used to interpret if the magma was provided by separate events from distinct sources or not, and whether the magmas formed by various degrees of partial melting from the same source and the degree of assimilation/contamination of these magmas.