University of Alberta EAS 331: Igneous Petrology Fall 2011

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1 University of Alberta EAS 331: Igneous Petrology Fall 2011 Instructor: Robert W. Luth Office: ESB Course Web Page: eclass Office Hours: Thursday or by appointment Lecture: CEB 321, MWF Laboratory Sections: ESB 3-12 Calendar Description: A survey of igneous rocks from the ocean basins and the continents; their field settings, classification, petrography, mineralogy and chemistry; magmatic processes and petrogenesis; problem solving and laboratory work on major rock suites. Course Prerequisites: CHEM 101 (or SCI 100), EAS 232, and EAS 320 (EAS 320 can be taken at the same time, as a co-requisite). Do not try and take this course without the pre-/co-requisites! Course Objectives: This course is an introduction to the study of igneous rocks, building on students previous coursework in introductory earth sciences (EAS 100 and 105) and in mineralogy (EAS 224 and 232). The course covers the knowledge and skills to classify igneous rocks, and the theoretical background to be able to place these rocks in the context of where, why, and how they form on Earth. The geochemical aspects of this course complement, and are complemented by, what students learn in EAS 320 (Geochemistry). This course provides prerequisite knowledge for courses such as EAS 332 (Metamorphic Petrology), EAS 333 (Advanced Geology Field School), EAS 432 (Precambrian Geology), EAS 466 (Petrogenesis), and EAS 467 (Planetary Geology). Required Textbook: Winter, J.D. (2010) Principles of (or An Introduction to) Igneous and Metamorphic Petrology, 2nd edition. The cover says Principles of..., the front matter says An Introduction to... Recommended or Optional Learning Resources: Notes and textbook from EAS 232 will be helpful in the laboratory portion of this course. Supplementary materials will be provided as handouts and materials posted on the course website. Organization of course: This course is divided into five units, as outlined below, along with the appropriate background readings in Winter s text. There is much more contained in the igneous portion of this textbook than can be learned in a single term. We will sample some topics briefly and some not at all. It would be ideal if you read over the appropriate material in the textbook before I talk about it petrology is difficult, and if you try to absorb everything just from class, it will be difficult. You should at least read over the appropriate section of the textbook after each class as needed to help with your understanding of the material. Rev. 25 Aug 2011 Page 1

2 Unit 1: Introduction and context 1. outline the plate tectonic model as a framework for conceptualizing igneous activity 2. describe the basics of any igneous system: melting evolution emplacement 3. describe the two basic mechanisms for producing diversity in igneous rock suites and relate them to their appropriate home in the igneous system 4. describe the variation in pressure and temperature with depth in the Earth. Unit 1 background reading: Winter, Chapter 1: sections 1.1, 1.2, 1.7, 1.8. Unit 2: Petrography of igneous rocks 1. write out the essential igneous minerals and their chemical formulae 2. describe the mode of emplacement (extrusive versus intrusive) inferred from the texture of a sample 3. produce an accurate petrographic description of a rock sample, including minerals present and their modes and texture 4. demonstrate basic terminology of igneous rocks by identifying the fields of the QAP, and be able to reproduce the mafic and ultramafic diagrams of the IUGS classification scheme 5. classify a rock sample both in terms of appropriate general labels (felsic/mafic, silicic/basic, etc), and with the IUGS classification scheme. Unit 2 background reading: Winter Chapters 2 and 3. Unit 3: Geochemistry of igneous rocks 1. describe how the chemistry of an igneous melt affects eruptive behaviour through its effects on viscosity and dissolved volatiles 2. graph major element geochemical data for a suite of samples and infer possible relationships between them 3. explain why the lanthanide elements figure so prominently in trace element geochemistry, and interpret a dataset featuring them 4. interpret isotope geochemical data (Rb/Sr and Sm/Nd) in terms of implications of origin and evolution of suite of rock samples. Unit 3 background reading: Winter Chapters 4, 8, 9 Unit 4: Magmatic processes 1. use simple phase diagrams to explain magmatic processes of melting and crystallization 2. outline the processes that produce partial melting in common tectonic environments 3. propose possible mechanisms of magmatic differentiation for a suite of rock samples that would relate them. Unit 4 background reading: Winter Chapter 6, 7 (sections 7.1.1, ), 10, 11, 12 (sections 12.1, , 12.3, 12.4). Rev. 25 Aug 2011 Page 2

3 Unit 5: Tectonic Environments 1. compare and contrast models of magmatic activity in different tectonic environments (DPB, CPB, intra-plate) 2. diagnose the possible tectonic context of a suite of rock samples, based on interpretation of the petrography and geochemistry of the suite. Unit 5 background reading: Winter Chapters Laboratory Sessions: The laboratory exercises are designed to complement material covered in lecture, and to provide hands-on experience to help the students learn the material and gain the skills necessary to complete the course successfully. They provide practical training in the identification, classification, and interpretation of igneous rocks based on hand samples and thin sections, and in dealing with mineralogical and geochemical data related to igneous rocks. Although the labs themselves are only worth 25%, actually doing them is essential for understanding the material and (more pragmatically, perhaps) doing well on the exams. You are expected to do the labs yourself; submission of work copied from others is an academic offense and will be dealt with according to the University s policies as set out in the Code of Student Behaviour. Some lab exercises are usefully done collaboratively, but what you submit must be your own work. The graduate teaching assistants are available for assistance during laboratory periods. They have other responsibilities, and are limited in the amount of time they are allowed to devote to this course, so students need to be aware that the GTAs are not required to have additional consultation hours outside of the lab periods, so it would be unwise to expect them to. Please bring your hand lens and appropriate reference materials for mineral identification to lab. Tentative Laboratory Schedule: Week of 9/12: Lab 1. Introduction to petrography Week of 9/19: Lab 1 (continued). Lab 1 is due at the end of the lab session. Week of 9/26: Lab 2. Magma chamber processes: layered mafic intrusions Week of 10/03: Lab 2 is due at the beginning of the lab session. Lab 3. Basalts and ultramafic rocks. Week of 10/10: Lab 3 (continued). Lab 3 is due at the end of the lab session. Week of 10/17: Lab exam I. Week of 10/24: Lab 4. Phase Diagrams. Week of 10/31: Lab 4 is due at the beginning of the lab session. Lab 5. Intermediate to felsic calc-alkaline rocks Week of 11/07: Thursday Fall Term Class Break; Friday Remembrance Day. No labs scheduled this week. Week of 11/14: Lab 5 (continued); Lab 5 due at end of lab session. Week of 11/21: No lab scheduled; time allocated for students to work on Tectonic/Igneous connection paper or to review material for the second lab exam. Week of 11/28: Lab exam II. Rev. 25 Aug 2011 Page 3

4 Evaluation: A letter grade will be assigned for your performance in this course. Grades will be based upon your earned percentage of cumulative marks and subsequent analysis of the class s grade distribution. The final grade distribution will be based on the University s suggested grade distribution for a 300-level course, and my judgement of the overall calibre of this class relative to past classes. In past years, the mean grade in this course has been in the B- to B range. Thus your grade will reflect a combination of absolute achievement and relative standing in the class. EXAMS and ASSIGNMENTS WEIGHTING DATE Lecture Examination I 10% Oct. 05 Lecture Examination II 10% Nov. 14 Lecture Final Examination 30% Dec. 20* Lab Assignments 25% as per schedule Lab Examination I 10% Week of Oct. 17 Lab Examination II 10% Week of Nov. 28 Tectonic Setting/Igneous rock brief: 5% Dec. 7 *WARNING: Students should verify this date on Bear Tracks when the Final Exam Schedule is posted. Past Evaluative Materials: Past examinations will be posted on the course website to illustrate the types of questions that will be posed on the examinations. Note that I changed to the two lecture exam plus final format in 2009, so older midterms will be of limited utility, but they will give you a sense of the style of questions I have tended to ask in the past. Missed Term Exams and Assignments: A student who cannot write a term examination or complete a term assignment because of an incapacitating illness, severe domestic affliction or other compelling reasons can apply for a deferred midterm examination or an extension of time to complete the assignment. Applications for both are to be made in writing to the professor, within 48 h of the missed exam or assignment due date. Please consult with me regarding necessary supporting documentation. Deferral of term work is a privilege, not a right; there is no guarantee that a deferral will be granted. Misrepresentation of facts to gain a deferral is a serious breach of the Code of Student Behaviour. Deferred Final Examination: A student who cannot write the final examination because of an incapacitating illness or is suffering from severe domestic affliction or other compelling reasons can apply for a deferred final examination. Such an application must be made to the student s Faculty office within 48 hours of the missed examination. Misrepresentation of facts to gain a deferred examination is a serious breach of the Code of Student Behaviour. If required, the deferred final examination will be held at 9 am on Saturday, 21 January Location TBA. Student Responsibilities: ACADEMIC INTEGRITY: The University of Alberta is committed to the highest standards of academic integrity and honesty. Students are expected to be familiar with these standards regarding academic honesty and to uphold the policies of the University in this respect. Students Rev. 25 Aug 2011 Page 4

5 are particularly urged to familiarize themselves with the provisions of the Code of Student Behaviour (online at and avoid any behaviour which could potentially result in suspicions of cheating, plagiarism, misrepresentation of facts and/or participation in an offence. Academic dishonesty is a serious offence and can result in suspension or expulsion from the University. All forms of dishonesty are unacceptable at the University. Any offense will be reported to the Senior Associate Dean of Science who will determine the disciplinary action to be taken. Cheating, plagiarism, and misrepresentation of facts are serious offenses. Anyone who engages in these practices will receive at minimum a grade of zero for the exam or paper in question and no opportunity will be given to replace the grade or redistribute the weights. As well, in the Faculty of Science the sanction for cheating on any examination will include a disciplinary failing grade (no exceptions) and senior students should expect a period of suspension or expulsion from the University of Alberta. EXAMS: Your student photo I.D. is required at exams to verify your identity. Students will not be allowed to begin an examination after it has been in progress for 30 minutes. Students must remain in the exam room for at least 30 minutes from the time the exam commenced. Electronic equipment is not to be brought to exam and hats are not to be worn. CELL PHONES: Please turn off cell phones during lectures and labs. Cell phones are not to be in your possession during exams; leave it home or put it away in your backpack. STUDENTS WITH DISABILITIES: Students who require accommodation in this course because of a disability are advised to discuss their needs with Specialized Support & Disability Services (2-800 Students Union Building). Policy about course outlines can be found in section 23.4(2) of the University Calendar. Disclaimer: Any typographical errors in this Course Outline are subject to change and will be announced in class. The date of the final examination is set by the Registrar and takes precedence over the final examination date reported in this syllabus. Rev. 25 Aug 2011 Page 5