IgneousIgneous PetrologyPetrology

Jean-François Jean-François MoyenMoyen

Practical informations

• Venues, dates, times

• Contact

• Textbooks

• Outline

Outline

1. Classification of igneous rocks2. Analytical techniques; major and trace

elements3. Isotopes4. Magma genesis: melting processes5. Magma evolution: cristallization, mixing, etc.6. Geochemical signature of mgmatic processes7. Magma transport and emplacement8. Volcanic processes

Outline

9. Basalts

10. Andesites

11. Granites

12. Alkaline complexes

13. Igneous rocks in a plate tectonic context

14. Revisions etc.

April break: 2 days field trip

Introduction to Introduction to igneous petrologyigneous petrology

Stromboli (Italy)

Etna (Italy)

Piton de la Fournaise (Réunion, Indian Ocean)

Torres del Paine, S. Chile

Ploumanac’h, France

Cantal extinct volcano, France

« Ignimbrites », Turkey

Bournac volcanic pipe, France

Montserrat, Lesser antilles (1997)

The upper part of the solid Earth

Crust•Oceanic

•Continental

Mantle•Lithosphere

•Astenosphere

The Pressure Gradient

• P increases = gh

• Nearly linear through mantle~ 30 MPa/km

1 GPa at base of ave crust

• Core: incr. more rapidly since alloy more

denseFigure 1-8. Winter, From Dziewonski and Anderson (1981). Phys. Earth Planet. Int., 25, 297-356. © Elsevier Science.

Heat Sources in the Earth

1. Heat from the early accretion and 1. Heat from the early accretion and differentiation of the differentiation of the

EarthEarth still slowly reaching surfacestill slowly reaching surface

2. Heat released by the radioactive 2. Heat released by the radioactive breakdown of unstable nuclidesbreakdown of unstable nuclides

The Geothermal Gradient

Figure 1-11. Winter, from Green and Falloon ((1998), Green & Ringwood (1963), Jaupart and Mareschal (1999), McKenzie et al. (2005 and personal communication), Ringwood (1966), Rudnick and Nyblade (1999), Turcotte and Schubert (2002).

Active volcanoes

Plate Tectonic - Igneous Genesis

1. Mid-ocean Ridges

2. Intracontinental Rifts

3. Island Arcs

4. Active Continental

Margins

5.5. Back-arc BasinsBack-arc Basins

6.6. Ocean Island BasaltsOcean Island Basalts

7.7. Miscellaneous Intra-Miscellaneous Intra-Continental Continental

ActivityActivity kimberlites, carbonatites, kimberlites, carbonatites,

anorthosites...anorthosites...