Geol 2312 Igneous and Metamorphic Petrology
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Transcript of Geol 2312 Igneous and Metamorphic Petrology
GEOL 2312 IGNEOUS AND METAMORPHIC PETROLOGY
Lecture 1Introduction to Igneous Petrology and Earth’s Physical and Chemical Structure
Jan. 20, 2009
THE REALM OF IGNEOUS AND METAMORPHIC
ROCKS
A Fundamental Dilemma to the Study of Igneous and Metamorphic Rocks and the Processes that Create
ThemACCESS
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 Cr
ysta
llizat
ion
Expe
rimen
ts
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 InterfaceGhiorso & 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-making1. Mantle partially melts to make ocean crust2. Ocean crust melts to make continental crust
1. Mid-ocean Ridges2. Intracontinental
Rifts3. Island Arcs4. Active Continental
Margins
5. Back-arc Basins6. Ocean Island
Basalts7. Miscellaneous Intra-
Continental Activity kimberlites, carbonatites,
anorthosites...
TECTONO-MAGMATIC ENVIRONMENTS