Syllabus (GEOLOGY)

Course Type: MAJ-7

Semester: 5

Course Code: BGELMAJ07C

Course Title: Igneous Petrology

(L-P-Tu): 4-2-0

Credit: 6

Practical/Theory: Combined

Course Objective: Igneous petrology as a branch of petrology it gives a knowledge regarding magma devitrification and also throws light upon upper mantle composition of earth interior.

Learning Outcome: students learn to apply the knowledge to explore minerals in igneous rocks.

Theory:

Unit I: Basics of Igneous Petrology

1. Modes of magma formation

2. Physical properties of magma - temperature, viscosity, density, and volatile content

3. Mode of occurrence and emplacement of different igneous rocks

4. Forms of igneous rock bodies

Unit II: Texture and microstructure of Igneous rocks

1. Crystallinity, granularity, shapes and mutual relations of grains; nucleation and growth of igneous minerals

2. Description of the following textures and microstructures with their occurrence in different rocks - panidiomorphic, hypidiomorphic, allotriomorphic, porphyritic, vitrophyric, poikilitic, ophitic, sub-ophitic, intergranular, intersertal, pilotaxitic, trachytic, graphic, granophyric, rapakivi, orbicular, corona, perthitic, myrmekitic, variolitic, speherulitic & spinifex

Unit III: Classification and Petrography of Igneous rocks

1. Introduction and bases of classification of igneous rocks; mineralogical, textural, chemical, chemico- mineralogical and associational

2. Norm and Mode. Standard classification schemes – Niggli, Hatch & Wells and IUGS. TAS diagram for volcanic rocks

3. Composition and texture of important igneous rocks: Granitoids, Pegmatite, Syenite, Monzonite, Diorite, Norite, Gabbro, Anthrothosite, Dolerite, Pyroxenites, Peridotite, Lamprophyres, Carbonatite, Rhyolite, Andesite, Dacite, Basalt, Komatiite.

Unit IV: Phase diagram for Igneous petrology

1. Introduction to phase rule and phase diagram

2. Phase Rule and its application to eutectic, peritectic and solid solution system

3. Phase equilibria in the following binary and ternary systems, and their petrogenetic significance: diopside – anorthite, forsterite – silica, albite – anorthite, albite – orthoclase, diopside – albite – anorthite, forsterite – diopside – silica and nepheline - kalsilite – silica.

Unit V: Diversification and chemical evolution of magma

1. Bowen’s reaction Series and its application.

2. Magma generation in crust and mantle, their emplacement and evolution

3. Magma series, Magmatic evolution, Magmatic differentiation- fractional crystallization, partial melting, assimilation, and their role in magmatic differentiation.

4. Chemical variation diagrams

Unit VI: Petrogenesis of Igneous rocks

1. Petrogenesis of Felsic and Mafic igneous rocks: Granitoids, Basalt, Gabbros, Anorthosite.

Unit VII:Magmatism in different tectonic settings

1. Mid Oceanic Ridge setting

2. Subduction Zone setting

3. Continental and oceanic rift zone setting

List of Practicals

1. Study of important igneous rocks in thin sections: granite, granodiorite, diorite, syenite, nepheline syenite, gabbro, anorthosite, ultramafic rock, basalt, andesite, dolerite, rhyolite, dacite.

2. Norm calculation for silica undersaturated and silica oversaturated rocks

3. Plotting of modal data in IUGS classification diagram for plutonic rocks (Streckeisen diagram).

Suggested Reference Books:

• Philpotts, A. and Ague, J. (2009). Principles of igneous and metamorphic petrology. Cambridge University Press.

• Winter, J. D. (2014). Principles of igneous and metamorphic petrology. Pearson.

• Raymond, L. A. (2002). Petrology: the study of igneous, sedimentary, and metamorphic rocks. McGraw-Hill Science Engineering.

• Myron G. Best (2001). Igneous and Metamorphic Petrology.

• Cox, K. G. and Bell. J. D. (1979). The Interpretation of Igneous Rocks. Springer/Chapman and Hall.

• Bose M. K. (1997). Igneous Petrology.

• Frost B. R. and Frost C. D (2014). Essentials of Igneous and Metamorphic Petrology. Cambridge University Press.

• Pitcher, W.S. 1997.The Nature and Origin of Granitic Rock. Springer.