Earth Sciences

AIMS

This course aims to provide students with a thorough understanding of the nature and origin of igneous rocks, from their formation and distribution to their volcanic exporessions and association with particular plate tectonic settings and to what extent these features have remained the same or changed with time during the geological history of the Earth.  The course also builds on fundamental concepts of geochemistry and mineralogy to explain phase behaviour in high temperature systems, and dynamic processes which can, for example, lead to formation of primary igneous ore bodies.  Integral practical classes will use both hand specimens and optical mineralogy to understand diagnostic textures - which are used to identify and classify igneous rocks.

OUTCOMES

Students should:

•     know the terminology applied to important families of igneous rocks;

•     recognize and identify igneous rocks, and their constituent minerals;

•     be able to provide a petrographic description of igneous rocks, their mineral compositions and textures;

•     understand the processes by which igneous rocks are formed;

•     be able to describe the tectonic settings in which igneous rocks occur including a preliminary assessment of volcanic hazard.

CONTENT

A comprehensive overview of the processes involved in forming igneous rocks, including the geological environments in which igneous rock families are located. This will be based on their mineralogical and geochemical characteristics including major isotope systems, to identify mantle and crustal signatures. Weekly themes will typically include the following: silicate phase equilibria in magmatic systems; partial melting; large basaltic igneous provinces; magmatic differentiation; distribution and occurrence of magma types, volcanoes, pyroclastics and volcanic hazards; alkaline rocks,carbonatites and kimberlites; komatities and ultrabasic rocks.

Modern petrological analytical techniques, including the electron and ion microprobes, and high pressure experimental techniques will also be introduced.