Transcript Geol 2312 Igneous and Metamorphic Petrology

GEOL 2312
IGNEOUS AND METAMORPHIC
PETROLOGY
Lecture 1
Introduction to Igneous Petrology and
Earth’s Physical and Chemical Structure
Jan. 20, 2009
A Fundamental Dilemma to the Study of Igneous and
Metamorphic Rocks and the Processes that Create Them
ACCESS
THE REALM OF
IGNEOUS AND
METAMORPHIC
ROCKS
IGNEOUS PETROLOGY
“Study of Rocks formed by the Crystallization of Magma”
What do we want to know about magma?
What do we want to know about crystallization processes?
How do we study igneous rocks to address these questions?
COMPONENTS OF SCIENTIFIC “STUDY”
OBSERVATIONS/INTERPRETATIONS
OF THE NATURAL WORLD
Melting
Experiments
Crystallization Experiments
COMPONENTS OF SCIENTIFIC “STUDY”
OBSERVATIONS/INTERPRETATIONS OF
EXPERIMENTS SIMULATING THE NATURAL WORLD
COMPONENTS OF SCIENTIFIC “STUDY”
OBSERVATIONS/INTERPRETATIONS OF
THEORETICAL MODELS THE OF NATURAL WORLD
Cobra MELTS Interface
Ghiorso & Sack (1995)
PHYSICAL AND CHEMICAL STRUCTURE OF
EARTH
PRESSURE AND THERMAL GRADIENTS
From Winter (2001)
COMPOSITION OF THE EARTH
How Do We Know?
- Mantle Xenoliths
- Seismic Data
- Density Constraints
- Meteorites
- stony ~mantle
- iron ~core
- chondrites ~whole
earth
Plate Tectonics drives Two Stages of Crust-making
1. Mantle partially melts to make ocean crust
2. Ocean crust melts to make continental crust
TECTONO-MAGMATIC ENVIRONMENTS
1. Mid-ocean Ridges
2. Intracontinental
Rifts
3. Island Arcs
4. Active Continental
Margins
5. Back-arc Basins
6. Ocean Island Basalts
7. Miscellaneous IntraContinental Activity

kimberlites, carbonatites,
anorthosites...