PTROLOGY
(Theatrical course book for the academic year 2014-2015)
B.Sc. Course 2nd stage Department of Geology Faculty of Science and Science Education School of Science University of Sulaimani Contents:
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Petrology (Theatrical) Course Book Faculty: Science and Science Education School: Science Department: Geology Course: Petrology (Theatrical)/ 2nd year students Course coordinator: Dr. Bakhtyar M. Ameen and Dr. Mushir M.Q. Baziany Lecturers of the course:
1. 2.
Name Dr. Bakhtyar M. Ameen
Scientific title Professor
E-mail
[email protected]
Dr. Mushir M.Q. Baziany
Lecturer
[email protected]
Course overview Petrology - The branch of geology dealing with study the origin, occurrence, structure, and history of rocks. Petrology is an important component of geology education that deals with the study of rocks (Igneous, Sedimentary and Metamorphic) The petrology is considered a vital link between basic geological science ( petroleum , Hydrogeology , Geochemistry ….etc) , and other science like( Engineering , Agriculture …… etc.)
(NB) Petrology course includes: 1. Theoretical lectures ( 2 hours per week) for 30 weeks ( 60 hours per a study years) 2. Practical lectures ( 3 hours –lectures per week) for 30 weeks ( 90 hours per a study years)
Course Objectives The main target of teaching of petrology course is to provide the students with Comprehensive knowledge of all geological processes (weathering, erosion, transportation, deposition and digenesis) which causes and leads to forming the different types of the rocks.
By the end of the course, the student expected to be able: 1. To differentiate economic component of rocks from non-economic ones. 2. To make the classification of the rocks and using the scientific international terms. 3. To know the composition of the earth. 4. To know the environment of earth interior such as P and T, and environment of the earth surface such as Salinity and depth. 2
Course references: a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blatt , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology e. Sam Boggs , 2009 Petrology of Sedimentary Rocks
f. www.petrology.net g. www.Igneous rocks.net h. www.Metamorphic rocks.net i.www.Sedimentary rocks.net Syllabus Seq. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Subjects Description of Petrology Igneous petrology – Introduction Magma Characteristic of igneous rocks Textures of igneous rocks Classification of igneous rocks The Phase Rule Sedimentary Petrology- Introduction and Definition Characteristics of sediments and sedimentary rocks Sedimentary Processes Composition of sedimentary rocks Textures of Sedimentary Rocks Sediment Maturity , porosity & permeability Sedimentary structures Classification of sedimentary rocks (Clastic Sedimentary Rocks) Classification of sedimentary rocks (Chemical Sedimentary Rocks) Classification of sedimentary rocks (Organic Sedimentary Rocks)
Lecturer Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr. Mushir M. Qadir Dr. Mushir M. Qadir Dr. Mushir M. Qadir Dr. Mushir M. Qadir Dr. Mushir M. Qadir Dr. Mushir M. Qadir Dr. Mushir M. Qadir Dr. Mushir M. Qadir Dr. Mushir M. Qadir Dr. Mushir M. Qadir
Digenesis Compaction and Cementation Dolomitization and Silicification Metamorphic Petrology-Introduction Metamorphic Factors Types of Metamorphism Zone and Grade of Metamorphism Fabrics (textures) of Metamorphism Metamorphic Minerals Origin and Occurrence of Metamorphism Metamorphic Facies
Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen Dr.Bakhtyar M. Ameen
First Examination
Second Examination 3
Subjects Subject 1: Description of Petrology Lecturer: Professor Dr. Bakhtyar M. Ameen Objective: To give the student a basic knowledge about the definition of the rocks, and how over time rocks are recycled into other rocks, which the moving tectonic plates are responsible for destroying and forming many types of rocks. The important question is: Why we study the rocks? Scientific contents 1. Definition of petrology, Petrography and Petrogenesis 2. Rock cycle 3. Economic component 4. Classification of the rocks References: a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. 4
c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology e. Sam Boggs , 2009 Petrology of Sedimentary Rocks f. www.petrology.net
Subject 2: Igneous petrology - introduction Lecturer: Professor Dr. Bakhtyar M. Ameen Objective: To give the student the definition of the Igneous rocks, (Fire Rock ) which is formed through volcanic action or the rocks which are derived from a molten mass “magma or lava” , after cooling a magma and makes crystals. Scientific contents 1. Definition of igneous rocks 2. Magma and lava as a molten mater References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology
e. www.petrology.net Subject 3: Magma Lecturer: Professor Dr. Bakhtyar M. Ameen Objective: To give the student an idea about the definition of the magma which is regards as a parent of the igneous rocks) , and the most abundant elements in earth The important question is: which is the parent of the igneous rocks? Scientific contents 1. Characteristics of Magma 2. Types of Magma 3. Gases in Magmas 4. Temperature of Magmas 5. Viscosity of Magmas References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology e. www.Igneous rocks.net
Subject 4: Characteristic of igneous rocks 5
Lecturer: Assistant professor Dr. Bakhtyar M. Ameen Objective: To give the student a basic knowledge about the definition of the rocks, and how over time rocks are recycled into other rocks, which the moving tectonic plates are The important question is: What is the composition of the magma? Scientific contents 1. Bowen’s Reaction Series 2. Magma Formation (types of the magma) 3. Melting and Partial melting 4. Cooling and Fractional crystallization 5. Evolution of magmas: Magmatic differentiation and Assimilation References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d . Myron G. Best, 2002, Igneous and Metamorphic Petrology
e.www.Igneous rocks.net Subject 5: Textures of igneous rocks (Mode of Occurrence) Lecturer: Professor Dr. Bakhtyar M. Ameen
Objective: To give the student a knowledge about the characteristics of intrusive (plutonic) and extrusive (volcanic) igneous rocks, also the different types of textures and structures with factors affecting crystal size. The important question is: Classify the igneous rocks according to the textures? Scientific contents 1. Bowen’s Reaction Series 2. Magma Formation (types of the magma) 3. Melting and Partial melting 4. Cooling and Fractional crystallization 5. Evolution of magmas: Magmatic differentiation and Assimilation References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002, Igneous and Metamorphic Petrology e. www.Igneous rocks.net
Subject 6: Classification of igneous rocks according to silica content Lecturer: Assistant professor Dr. Bakhtyar M. Ameen
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Objective: To give the student a knowledge about the classification of igneous rocks depending on silica saturation, colour index (percentage% of dark-coloured minerals in a rock) and mineralogy The important question is: Classify the igneous rocks according to the silica saturation? Scientific contents 1. Silica Content 2. Colour index 3. Mineralogy Classification References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blatt , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002, Igneous and Metamorphic Petrology
Subject 7: The Phase Rule Lecturer: Professor Dr. Bakhtyar M. Ameen
• Objective: To give the student a knowledge about the melts behavior and how the factors of temperature and pressure causes changing of the melt composition during crystallization also the number of minerals which increase as T decreases and how the pressure of the volatiles can also affect the minerals and their sequence The important question is: How the melt composition changes during crystallization ? Scientific contents 1. Crystallization behavior of melts 2. Phase rule References: a. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. b. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology c . Myron G. Best, 2002, Igneous and Metamorphic Petrology
Subject 8: First Examination
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Subject 9: Sedimentary Petrology-
Introduction and Definition
Lecturer: Dr. Mushir M. Qadir
Objective: To give the student a basic knowledge about the definition of the sedimentary rocks and to give the idea about the composition, characteristic and origin of sediments and sedimentary rocks. The question is: What is the economic importance of sedimentary rocks? Scientific contents 1. Characteristic of sediments and sedimentary rocks 2. Stratification 3. Bedding: References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. Pettijohn, F. J., 1975. Sedimentary Rocks
e. www.Sedimentary rocks.net Subject 10: Sedimentary Petrology Characteristics of sediments and sedimentary rocks Sedimentary Processes Lecturer: Dr. Mushir M. Qadir
Objective: To give the student a basic knowledge about the geological processes which leads to the formation of sedimentary rocks. The question is: How are sedimentary rocks formed? Scientific contents 1 – Weathering and Erosion 2 - Transportation 3 – Deposition 4 – Burial 5 - Lithification References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. Pettijohn, F. J. 1975. Sedimentary Rocks
e. www.Sedimentary rocks.net
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Subject 11: Sedimentary Petrology Composition of sedimentary rocks Lecturer: Dr. Mushir M. Qadir
Objective: To give the student a basic knowledge about composition of sedimentary rocks and the type of minerals (allogenic and authogenic). Also to give an idea about the common minerals in sedimentary rocks The question is: What is the economic importance of sedimentary rocks? Scientific contents 1. Detritus sediment 2. chemical sediment 3. Biogenic sediment
References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. Pettijohn, F. J. 1975. Sedimentary Rocks
e. www.Sedimentary rocks.net Subject 12: Sedimentary Petrology Textures of sedimentary rocks Lecturer: Dr. Mushir M. Qadir
Objective: To give the student a basic knowledge about the relation between the grains, so during the study of texture can explained the deposition and also to give the idea about maturity, which it is a function of time and the intensity of the actions (processes). The question is: What are the features you must study to determine the maturity? Scientific contents 1. Stability of Minerals 2. Rock Fragments 3. Rounding or Angularity 4. Sorting 5. Removal of Unstable Ingredients - Mechanical Working References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. Pettijohn, F. J.,1975. Sedimentary Rocks
e. www.Sedimentary rocks.net Subject 13: Sedimentary Petrology Sediment Maturity, porosity & permeability Lecturer: Dr. Mushir M. Qadir 9
Objective: To give the student a basic knowledge about the Maturity, porosity & permeability and also to show evidence of transporting with rounding of the grains and size sorting. The question is: What are the factors can control the maturity? Scientific contents 1. Maturity 2. Porosity 3. Permeability References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. Pettijohn, F. J., 1975. Sedimentary Rocks
e. www.Sedimentary rocks.net Subject 14: Sedimentary Petrology Sedimentary structures Lecturer: Dr. Mushir M. Qadir Objective: To give the student a basic knowledge about the all sedimentary structures that have a relation between the factor of transportation with environment, coarse which deposited in high energy (fast water) environments such as under breaking waves at the beach, or in the beds of fast streams, while fine sediments low energy environments, e.g. the slow water of deep lagoons, the abyssal plain, etc. The question is: What are the mainly sedimentary structures regards good indicators for paleo currents analysis? Scientific contents 1. Sedimentary Structure 2. Turbidity currents 3. Environment energy References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. Pettijohn, F. J., 1975. Sedimentary Rocks
e. www.Sedimentary rocks.net Subject 15: Sedimentary Petrology Classification of sedimentary rocks (Clastic Sedimentary Rocks) Lecturer: Dr. Mushir M. Qadir
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Objective: To give the student a basic knowledge about the grains formed by the physical sedimentary processes like clastic grins composition and size and to show evidence of transporting with rounding of the grains and size sorting. The question is: What are the factors can control the size and shape of grains? Scientific contents 1. Clastic sedimentary rocks 2. Conglomerate and breccia 3. Sandstone 4. Murdock
Subject 16: Sedimentary Petrology Classification of sedimentary rocks (Chemical and Organic Sedimentary Rocks) Lecturer: Dr. Mushir M. Qadir
Objective: To give the student a basic knowledge about the grains formed by direct precipitation or crystallization from water, the precipitation of solids from solutions (like salt from water) or by organic process like shells from marine organisms. Also to give idea about precipitation of material which occurs two ways: Inorganic processes: the minerals precipitate out of water and Organic processes: animals and plants precipitate the minerals to use as shells or skeletons. The question is: What are the mainly composition of carbonate rocks? Scientific contents 1. Chemical sedimentary rocks 2. Organic and Inorganic processes 3. Limestone, chert 4. Evaporate rocks References: a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. Pettijohn, F. J., 1975. Sedimentary Rocks
e. www.Sedimentary rocks.net Subject 17: Digenesis Lecturer: Professor Dr. Bakhtyar M. Ameen Objective: To give the student a basic knowledge about the all processes that lithifies sediments or makes them into a solid sedimentary rock or changes in the sediment due to increased heat, pressure, and circulating groundwater. Also to all processes (chemical, physical and biological) that may occur at or very near surface, but more commonly occurs after sediments are buried. The question is: What are the processes that make sediments into a solid sedimentary rock? Scientific contents 1. Diagenetic Processes 2. Compaction 3. Recrystallization 4. Cementation 11
5. Lithification References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. Pettijohn, F. J., 1975. Sedimentary Rocks
e. www.Sedimentary rocks.net
Subject 18: Metamorphic Petrology-introduction Lecturer: Professor Dr. Bakhtyar M. Ameen Objective: To give the student a knowledge about the metamorphic rocks and the metamorphism which produce changing in mineral assemblages and textures that reflect re-equilibration of the rock to the new physicochemical conditions. The important question is: How do I recognise Metamorphic rocks? Scientific contents 1. Metamorphic rocks 2. Metamorphism References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blatt , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d . Myron G. Best, 2002 , Igneous and Metamorphic Petrology e. www.Metamorphic rocks.net
Subject 19: Metamorphic Factors Lecturer: Professor Dr. Bakhtyar M. Ameen
Objective: To give the student idea about the rocks adjust to become more stable under new, higher temperatures and pressures also changing the parent rock into a completely new rock and the parent rock can be either sedimentary, igneous, or even another metamorphic rock. The important question is: How do rocks change? Scientific contents 1. Heat 2. Pressure 3 .Chemical fluids References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology 12
d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology
e. www.Metamorphic rocks.net Subject 20: Types of Metamorphism Lecturer: Professor Dr. Bakhtyar M. Ameen
Objective: To give the student idea about the main ways that metamorphic rocks can form and the geological processes which leads to form these types, also mention to rocks which produce in each types of metamorphism. The area with position also very important to determine them. The important question is: Compare between regional and contact metamorphism? Scientific contents 1. Types of metamorphism References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology
e. www.Metamorphic rocks.net Subject 21: Zone and Grade of Metamorphism Lecturer: Assistant professor Dr. Bakhtyar M. Ameen
Objective: To give the student idea about the most metamorphic changes which occur at the high °T and pressure existing in the zone beginning a few km below earth’s surface, and extending into the upper mantle and how metamorphism progresses incrementally, from slight changes from low grade to substantial changes to medium in the last stage to high-grade. The question is: What are the factors affects the grade of metamorphism? Scientific contents 1. Grade and zone of metamorphism References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology
e. www.Metamorphic rocks.net Subject 22: Fabrics (textures) of Metamorphism Lecturer: Assistant professor Dr. Bakhtyar M. Ameen
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2) Objective: To give the student idea about the most types of metamorphic textures which seen in different types of igneous rocks and the factors which leads to form the different textures .Also how can pressure make the parallel arrangement with wavy-like appearance (foliated) resulting from crystals oriented in long axes perpendicular to the pressure ,while with out role of pressure crystals not oriented with long axes in one direction (Non-Foliated )textures. The question is: Define the textures which exist only in regional metamorphism ? Scientific contents 1. Fabric in metamorphism References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology
e. www.Metamorphic rocks.net Subject 23: Metamorphic Minerals Lecturer: Professor Dr. Bakhtyar M. Ameen
Objective: To give the student idea about the most types of metamorphic minerals which seen in different types of igneous rocks and the factors which leads to form the different types of minerals and knowledge about the index metamorphic minerals. The question is: Divide the metamorphic minerals depending on resistance to shearing stress and high temperature? Scientific contents 1. Metamorphic minerals References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology
e. www.Metamorphic rocks.net Subject 24: Origin and Occurrence of Metamorphism Lecturer:Professor Dr. Bakhtyar M. Ameen
Objective: To give the student idea about the single source rock (Parent rock) can be changed into various metamorphic rocks, depending on type and intensity of metamorphism. The question is: Why the source determination is important for the metamorphic minerals. 14
Scientific contents 1. Origin of Metamorphism References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic petrology
e. www.Metamorphic rocks.net Subject 25: Metamorphic Facies Lecturer: Professor Dr. Bakhtyar M. Ameen
Objective: To give the student idea about the metamorphic facies which is a domain of Pressure-Temperature space, and the characteristic mineral assemblages specific to particular bulk-rock compositions in different types of facies. The question is: Compare between contact and regional facis? Scientific contents 1. Metamorphic Facies References:
a. Loren A.Raymond:2007, Petrology. The study Igneous, Sedimentary and Metamorphic b. Harvey Blat , Robert Tracey and Brent Owens , 2005, Petrology. c. john D. Winter, 2009 , Principles of Igneous and Metamorphic Petrology d. Myron G. Best, 2002 , Igneous and Metamorphic Petrology
e. www.Metamorphic rocks.net
Subject 26: Forth Examination Exams A. Times of exams The following pattern of examinations is depended for the petrology course: 1. First month exam (mid first semester exam): (5 marks) The first exam is usually taken by the mid of the first semester. 2. Second month exam (end first semester exam): (5 marks) The second exam is usually taken by the end of the first semester. 3. Third month exam (mid second semester exam): (5 marks) The third exam is usually taken by the mid of the second semester. 4. Fourth month exam (end second semester exam): (5 marks) The second exam is usually taken by the end of the first semester. 5. First practice exam (end first semester exam): (15 marks) The first exam is usually taken by the end of the first semester. 6. Second practice exam (end second semester exam): (15 marks) The second exam is usually taken by the end of the second semester. 15
7. The final exam (only include theoretical exam) The final exam is usually taken by the end of the second semester.
(50 marks)
B. Exams duration The duration of each monthly exam is 1.5 hours and final exam is 3 hours.
C. Answering technique by the student: Advices to the students are: 1. To read and think about the questions deeply before answering. 2. If the student doesn’t know the correct answer of a particular question, in this case there is not benefit fro wasting the time and its better to skip it and go to the next, and at the last when there is a space can go back and try to answer the skipped question.
D. Type and samples of exams: 1. Multiple choice questions: Examples: 1. Choose the suitable answer of the following statements: 1. Density of the magma (decrees - not change - increase) during the crystallization. 2. (Basaltic – Rhyolitic - Andesetic) magma is high in Fe, Mg, Ca, and low in K, Na. 3. Pressure along fault zones causes (dynamic – regional - contact) metamorphism, 4. Marble is a coarse crystalline network of (quartz – biotite - calcite) grains that form as a result of recrystallization.
1. True and false questions. Examples: Answer (in the space provided) by (T) for each correct statement, (F) for each incorrect statement and (D) if you don’t now the answer. a. (T) Sedimentary rocks are composed of particles derived from pre-existing rocks. b. (F) Pigmatite form in fist stages of crystallization of basaltic magmas c. (D) Metamorphic rocks are exposed during metamorphism the rocks change without leaving the solid state.
2. Complete these statements by filling the blanks a. The word sedimentary comes from the Latin world sedimentum, which means “settling” . b. Pressure along fault zones causes Dynamic Metamorphism. c. Magma is a hot liquid made of melted minerals.
3. Definitions. Examples: 16
Define the following petrological terms: a. Dike: Magma is squeezed into across-cutting fracture and solidified to form a dike.
b. Metamorphism Produces changes in mineral assemblages and textures that reflect re-equilibration of the rock to the new physicochemical conditions.
c. Weathering Physical and chemical breakdown of earth material (rocks and minerals) at or near the surface. Includes disaggregation of parent materials.
4. Compositional questions. Examples:
a. Give the reason of the following:
1. All parts of rock don’t melt in the same time .Why? Some parts of the rock don’t melt easily because rock composed of different minerals so the different minerals with varying melting points).
2. Fossils are rarely seen in metamorphic rock. Why? They are distorted and misshapen due to metamorphism factors likes pressure and temperature. 3. Sedimentary rocks have the economic importance. Why? They are important for economic reasons because they contain • Coal • Petroleum and natural gas • Iron, aluminum, uranium and manganese • Geologists use them to read Earth’s history
b. Differentiate (in the table) between the Aphanitic and Phaneritic textures Characteristics
Aphanitic 17
Phaneritic
1- Occurrences
Volcanic
Plutonic
2- Degree of cooling
Rapid rate of cooling of lava or magma
Slow cooling
3- Grains size
Fine grain Microscopic crystals
Coarse grain Crystals can be identified without a microscope
4- Vesicles present
May contain vesicles (holes from gas bubbles)
Without vesicles
5- Rocks examples
Basalt
Granite
c. Explain (in ordered points) the deposition of sediment after transportation from source to depositional environment. Deposition is the process by which sediment settles out of the water or wind carrying it and accumulates sediments from large region. - Eventually, the moving water or wind slows and deposits the sediment. -If water is carrying the sediment, rock fragments and other materials sink to the bottom of a lake or ocean. -In addition to particles of rock, sediment may include shells, bones, leaves, stems, and other remains of living things. -Over time, any remains of living things in the sediment may slowly harden and change into fossils trapped in the rock. -These layers are pressed down more and more throw time, until the bottom layers slowly tern into rock.
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