Igneous and metamorphic rocks are the products of volcanoes and processes that take place deep within our Earth. This course will teach you about volcanoes, about how magmas are produced in the Earth’s mantle and crust, and about how heat and pressure change rocks and form a record of Earth history. Students learn about the most common techniques used to study these rocks including how to use field evidence, mineral assemblages, mineral textures and relationships observed under the optical microscope. The module will help you to develop an understanding of the theoretical frameworks used to interpret observations of minerals and rocks, and the methods used to interpret mineral assemblage and major, trace element and isotope geochemistry.
You will find the course difficult unless you have attended the first level Geology and Crystallography and Mineralogy modules, which are formal pre-requisites. It is important that you know the rock-forming minerals, their composition and identify characteristics at the outset of the module.
This module is suitable for students with some prior knowledge of geology, crystallography and mineralogy. Visiting students with an appropriate background may choose to attend either semester, with an igneous petrology focus in Semester 1 and a metamorphic focus in Semester 2. The module may also be taken by joint honours students, with an appropriate background.
The module introduces you to igneous and metamorphic processes and their plate tectonic context. The module develops the skills that will enable you to describe, identify and classify igneous and metamorphic rocks. You will also develop the concepts underpinning modelling of natural systems.
INTENDED LEARNING OUTCOMES (ILOs) (see assessment section below for how ILOs will be assessed)
On successful completion of this module, you should be able to:
Module Specific Skills and Knowledge:
1 Understand igneous and metamorphic processes and their related mineralogical and geochemical variations;
2 Identify, describe and classify igneous and metamorphic rocks;
3 Interpret field structures, textures and mineral assemblages;
4 Synthesise and interpret compositional variations of igneous and metamorphic rocks;
Discipline Specific Skills and Knowledge:
5 Appreciate deep processes in the lithosphere and asthenosphere that affect the nature of rocks observed at the surface of the Earth;
6 Demonstrate an ability to apply conceptual and modelling frameworks to problems by lateral thought processes;
Personal and Key Transferable / Employment Skills and Knowledge:
7 Demonstrate personal observational, descriptive and numerical skills, along with self- and time-management skills.
SYLLABUS PLAN - summary of the structure and academic content of the module
Igneous petrology :
- Present-day igneous activity;¨
- Melting and crystallisation processes;
- Magmatic differentiation;
- Binary and ternary phase diagrams in igneous petrology;
- Major and trace elements in igneous processes;
- Magma source regions and magma migration;
- Suites of magmatic rocks;
- Styles of volcanism and emplacement;
- Characteristic mineral assemblages and classification of igneous rocks;
- Origin of basalts, andesites, granites, alkaline rocks, and carbonatites;
- Cumulate rocks;
Metamorphic Petrology:
- Controls of metamorphism and metamorphic processes;
- Definitions and main settings of metamorphism;
- Metamorphic facies;
- Metamorphic equilibrium and phase diagrams;
- Metamorphic textures;
- Interrelations between metamorphism and deformation;
- Compositional groups;
- Characteristic mineral assemblages of metapelites, metabasites, and metacarbonates in low-, medium- and high-pressure facies series;
Practical Skills:
- Identification, description and interpretation of igneous and metamorphic textures and mineral assemblages in field, hand specimen, and thin section;
- Uses of phase diagrams, and major and trace elements in petrological studies.