[citation needed] Blundy is most noted for advancing the understanding of how magmas are generated in the Earth's crust and mantle and of the processes that occur in volcanoes before they erupt.
He undertook his PhD research at the University of Cambridge under the supervision of Professor Robert Stephen John Sparks on the granites of Adamello-Presanella in the Italian Alps.
In a series of papers with the notable Bernard Wood in the 1990s, Blundy popularized a theory of elastic strain originally developed by Onuma [7] to describe the uptake of trace elements into the crystal lattices of igneous minerals.
The theory was based on high temperature and pressure experiments on molten rocks, and is now widely used to predict crystal-melt partition coefficients for use in modelling magmatic processes.
Blundy subsequently collaborated with Katharine Cashman at the University of Oregon on Mount St. Helens volcano in the Cascade Range of northwestern USA.