The petrogenesis of magmatic systems : using igneous textures to understand magmatic processes.

An understanding of the petrogenesis of magmatic systems can be achieved by studying their constituent parts (e.g. crystals) and their chemical trends. Magmas are often travelling from source to emplacement levels together with a growing population of crystals. As they grow and respond to their environment through time, crystals can record the processes of contamination, magma mingling, crystal exchange and magma recharge occurring en route. Detailed quantification of the micro-scale textural parameters of igneous rocks such as crystal shape, size and spatial pattern provides important geometrical information about the crystal population, which can be linked with macroscale magmatic processes. The complex zoning often observed in crystals can also be quantified and linked back to the textures to show how magma chemistry changed during crystal growth. Finally, it is described how these techniques are developing toward 3D chemical mapping of igneous rocks as well as to record 4D experiments