ÖNCEL AKADEMİ: SOLID EARTH GEOPHYSICS
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This document provides an introduction and overview of a Solid Earth Geophysics course. It outlines the course details like instructor information, schedule, syllabus, grading, and assignments. It also gives a brief history of knowledge about Earth's interior over time. Seismology and drilling programs have provided insights into the internal structure through analyzing seismic wave speeds and bringing up material from depth. Body waves and surface waves help reveal properties of different layers. Temperature and pressure increase with depth due to overlying rock.
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ÖNCEL AKADEMİ: SOLID EARTH GEOPHYSICS
- 1. Solid Earth Geophysics-Geop503 Ali Oncel [email_address] Department of Earth Sciences, KFUPM Introduction to Solid-Earth Geophysics
- 2. Dr. Ali O. Oncel : Building 26, Room:319 (oncel@kfupm.edu.sa) Saturday. 14.00-16:00 PM room 319 Monday. 14:00-16:00 PM room 319 Any time you get appointment by e-mail or you can come to see me based on open-door policy. Scheduled Office Hours
- 3. Website Password: Geop503oncel http://geop503kfupm.pbwiki.com/
- 5. Course Book: The Solid Earth by C.M.R. Fowler-2005 Grading
- 7. Schedule: Weekly Presentation http://geop503kfupm.pbwiki.com/Geop503_Discussion_Paper
- 8. Presentation: Paper of the week 1 http://faculty.kfupm.edu.sa/ES/oncel/geop503reading.htm
- 9. Geophysics: Geology + Physics What is Geophysics?
- 10. Solid Earth Geophysics ? Understanding the Earth’s composition and dynamics, and their relationships with the surface geological phenomena, using the means of physics. Analogy: How do you figure out what is going on inside an apple, egg, golf ball, human body, without slicing it open? Suggestions: you can weigh it, spin it, heat it, probe it with electromagnetism, etc. You can also look at what is naturally emitted from it. What is the purpose of Solid-Earth Geophysics ?
- 11. Scope of Course Providing knowledge more about the mathematical and physical aspects of solid Earth geophysics such as the currently accepted physical models used to describe the Earth's interior and evolution. Providing knowledge about the most important datasets and methods which have been used to learn about Solid Earth Geophysics. Providing knowledge of how these datasets and application of the scientific method by many scientists, have been used to perform current models for the physical characteristics of the Earth, its chemical composition, and the past and ongoing processes modifying the Earth. Providing knowledge of the many exciting problems that still remain for research to be solved. What is the scope of studies on Solid-Earth Geophysics ?
- 12. Earth Formation What is the past knowledge on Earth’s Interior? http://www.seismosoc.org/about/memb_info.html Complete Archive of BSSA Back Issues from 1911-2006
- 13. What did we know about Earth between 1920-1930?
- 14. What did we know about Earth between 1940-1950?
- 15. Earth Formation The knowledge on Earth’s Interior in 1924 From what you can see, inner core has not been known, where Lehman , who is Danish Seismologist and died in 1993 aged 104, discovered the inner core in 1936.
- 16. Earth Formation Why temperature/pressure is increased with depth?
- 17. How do we know? MOHO Core-mantle boundary *Crustal thicknesses are depicted out of scale for clarity . Upper mantle evidence comes from mantle rocks thrust onto continents (e.g., ophiolites); xenoliths; lab experiments • Lower mantle completely based on experiments http://www.geo.cornell.edu/geology/classes/geol388/syl_04.html upper mantle “Peridotite”: 65% olivine : (Mg,Fe) 2 SiO 4 25% orthopyroxene (Mg,Fe) 2 Si 2 O 6 10% clinopyroxene (Ca,Mg,Fe) 2 Si 2 O 6 + garnet (Mg,Fe) 3 AL 2 Si 3 O 12 phase changes through transition zone lower mantle 85% Perovskite : (Mg 0.9 Fe 0.1 )SiO 3 15% magnesiowustite (Mg 0.9 Fe 0.1 )O + Ca Perovskite ( Ca, Mg, Fe )SiO 3 + Corundum Al 2 O 3 outer core 90% Fe +Ni alloy 10% lighter alloy (FeO, S, Si, ?) inner core solid Fe + ? continental crust* oceanic crust*
- 18. Internal structure by Drilling Program http://www.icdp-online.de/contenido/icdp/front_content.php The deepest drill hole is about 12 km deep, which doesn't even make it past the bottom of the crust. Certain volcanic eruptions can bring up material from deeper, but still less than 1000 km deep. How do we know by Global Drilling Program?
- 19. Internal structure by Seismology Seismology: When earthquakes happen, the ground shakes and seismic waves travel outward from the earthquake. If the earthquake is big enough, then the seismic waves can be detected on the other side of the earth. The speed of seismic waves is related to the properties of the material they travel through, and we can try to extract information on the properties of the Earth. How do we know by Seismology?
- 20. Shadow Zone - no earthquake waves
- 21. What are the main characteristics of Body waves ? P (primary or push) waves comparable to sound waves alternating dilatations and compressions transmitted through liquid or solid may be heard when they emerge at surface S (secondary or shear) waves slower traveling shears rock sideways perpendicular to direction of propagation not transmitted through liquid Some typical velocities (granite) P=4.8km/s S=3.0km /s Body Waves and Internal structure
- 22. What are the main characteristics of Rayleigh waves ? Travel just below or along the ground’s surface Surface Waves and Internal structure Especially damaging to buildings Slower than body waves; rolling and side-to-side movement Rayleigh Waves
- 23. Travel confined to near surface Wave displacements fall off rapidly with depth Love waves sideways motion perpendicular to travel motion like an S wave with no vertical component Rayleigh waves rolling motion involving vertical & horizontal displacements in direction of travel Surface waves travel more slowly than body waves What are the main characteristics of Love waves ? Love waves travel faster than Rayleigh waves and therefore arrive earlier Surface Waves and Internal Structure ? Love Waves
- 25. Assignment, Due to Monday Please also submit your short CV to Class Page. Just Click “Comments” on Front Page for submission. Mention about yourself, and your expectation with the class.
- 26. questions