Endogenous petrology

In the first part of this course unit, we will discuss the genesis and evolution of magmas from a petrological (microscopic observations of rocks and minerals, phase equilibrium) and geochemical (major element, trace element, and isotopic composition of minerals and rocks) perspective in different geodynamic contexts: ocean ridges, hot spots, and subduction zones.

In the second part of this course unit, we will introduce the main variables and different geodynamic contexts of metamorphism. You will learn to recognize mineral reactions and interpret them using the geometric rules of chemiography. We will discuss the concept of metastability and the influence of rock chemistry on their metamorphic evolution.

Hourly volumes:

CM: 9

TP: 18

Know how to identify the structures and textures of igneous and metamorphic rocks under a microscope and understand the conditions under which they formed in different geodynamic contexts.

Basic concepts of mineralogy and crystallography: definition of a mineral, what it is made of, what properties enable it to be identified, recognition of common minerals (macroscopy and microscopy).

Knowledge of geochemistry: concept of incompatible/compatible elements, partition coefficient, stable and radioactive isotopes, partial melting/fractional crystallization equation.

Recommended prerequisites:

The content of the "Earth and its Resources" courses in Year 1, and "Rocks and Minerals" and "Geochemistry" in Year 2 of the Earth-Water-Environment program is an ideal prerequisite for this course.

Assessment: Continuous assessment. Students will be assessed during the semester through three tests evaluating the practical and theoretical knowledge covered in lectures and practical classes.

• Brief description of the concepts covered in CM:

CM1 1.5 hours: Textures of igneous and metamorphic rocks.

CM2 1.5 hours: Genesis of igneous rocks in the context of ocean ridges and hot spots.

CM3 1.5 hours: - Genesis of magmatic rocks in the context of subduction and collision zones.

CM4 1.5 hours: Metamorphism and geodynamics: recent mountain ranges

CM5 1.5 hours: Metamorphism and geodynamics: ancient mountain ranges

CM6 1.5 hours: Texture of metamorphic rocks and introduction to the chemical representation of metamorphic reactions

• Brief description of practical sessions and number of hours associated with each session

TP1: Optical microscopy - Mineral identification using polarized/analyzed light.

TP2: Optical microscopy - Mineral identification using polarized/analyzed light.

TP3: Optical microscopy observations of magmatic rocks in the context of ocean ridges and hot spots.

TP4: Optical microscopy observations of magmatic rocks in the context of subduction and collision zones

TP5: Optical microscopy observations of metamorphic rocks

TP6: Observations of thin sections reflecting the Barrovian and Abukuma hot metamorphic gradients (MP/HT and LP/HT)

Skills targeted by the EU:

• Be able to recognize, at the microscopic level, the main minerals in igneous and metamorphic rocks, the texture and structure of rocks, and be able to deduce their formation conditions.
• Know how to relate the mineralogy, petrology, and geochemistry of rocks and discuss their genesis in their geodynamic context.
• Know how to work independently, describe, write, summarize.