1. Room: 407 Prey@mail.usyd.edu.au Tel: 12060 Patrice Rey

2. Lecturers are guides, they open doors and show paths to knowledge... Become an independent learner. There is no bad students, only bad learning habits. …but it’s up to you to do the journey. 1 hour of lecture should be followed by 2 hours of work involving reading and synthesizing information gathered from textbooks and other resources. Use the web and make the library your second home! Do not work alone. Consider lectures and practical classes for what they really are: introductions to knowledge. Most importantly: Get organized, work steadily, and have fun!

3. Lecture 1: Lithosphere, asthenosphere, and Archimedes (287- 212 BC) Aims: A brief reminder about the earth and lithospheric plates

4. Structural geology deals with deformation of earth materials: From minerals to tectonic plates ~15 plates travel at the surface of the earth @ a speed of a few cm/y Plates travel at various speed and in various direction...=> …seismicity and deformation at plates boundaries

5. Plate boundaries features Topography

6. Plate boundaries features Seismicity

7. Plate boundaries features Volcanism

8. Australian plate

9. Plate tectonics and things that happen @ plate boundaries

10. Divergent plate boundaries

11. Convergent plate boundaries

12. Transform fault, and strike slip fault boundaries

14. Earth’s structure

15. Continental lithosphere: Some physical characteristics Radiogenic upper crust Radiogenic elements U, Th, K Temperature

16. Continental lithosphere: Some physical characteristics (z c /z l )*  c +(z lm /z l )*  lm Density lithosphere ? Density

17. Isostasy and surface topography

18. Isostasy: A surface exists at a certain depth where the pressure, from the column of earth material above, is the same across and underneath the surface.

19. Continental lithosphere: Some physical characteristics Strong upper crust Weak upper crust Strong upper mantle Weak lower lithospheric mantle Very weak asthenosphere Strength

20. Lecture 1 at a glance ~15 plates move at the surface of the earth. Plate boundaries: locus of seismicity +/- magmatic activities, and high topography. Divergent, convergent, and transform plate boundaries. Lithospheric plates: oceanic lithosphere only, or both oceanic and continental lithosphere, they float on the asthenosphere. Strength of continental lithosphere Strong upper crust, weak lower crust, strong upper mantle, weak lower lithospheric mantle, very weak asthenosphere. Thickness Continental lithosphere: 180 +/- 100 km thick; Oceanic lithosphere: 0-100 km Continental crust: 35+/-10 km; Oceanic crust: 5-7 km Temperature Temperature at continental Moho: 500+/-150ºC Temperature at base of lithosphere: 1300 +/-100ºC Density Density continental crust: 2800 +/-100 kg.m -3 Density lithospheric mantle: 3350 +/-100 kg.m -3 Density asthenosphere: 3300 +/-100 kg.m -3