DOCSLIB.ORG

Evaluating Reaction Stoichiometry in Magmatic Systems Evolving Under Generalized Thermodynamic Constraints: Examples Comparing Isothermal and Isenthalpic Assimilation

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Evaluating Reaction Stoichiometry in Magmatic Systems Evolving Under Generalized Thermodynamic Constraints: Examples Comparing Isothermal and Isenthalpic Assimilation Magmatic Processes: Physicochemical Principles © The Geochemical Society, Special Publication No. I, 1987 Editor B. O. Mysen Evaluating reaction stoichiometry in magmatic systems evolving under generalized thermodynamic constraints: Examples comparing isothermal and isenthalpic assimilation MARK S. GHIORSO and PETER B. KELEMEN Department of Geological Sciences, University of Washington, Seattle, WA 98195, U.S.A. Abstract-Legendre transforms are utilized to construct thermodynamic potentials which are minimal in systems at thermodynamic equilibrium under conditions offixed enthalpy, volume and chemical potential of oxygen. Numerical methods that facilitate the minimization of these potentials are de- scribed. These methods form the core of an algorithm for the calculation of reaction stoichiometry for irreversible processes in open magmatic systems proceeding under isenthalpic or isochoric con- straints, or both. As an example of the use of these methods, calculations of isothermal and isenthalpic assimilation in fractionating basaltic magma are presented. Isenthalpic calculations are most useful in considering the effects of solid-liquid reactions which are endothermic. In general, such reactions involve the assimilation of a less refractory phase in a high temperature magma, or assimilation of phases across a cotectic "valley" in the liquidus surface. The mass of crystals calculated to form during isenthalpic assimilation of pelitic rock in a magnesian MORB is six to ten times as great if the rock is assumed to be at 500°C than if the rock is at 1250°C. The examples illustrate the necessity of characterizing the temperature and phase assemblage, as well as the bulk composition, of the assimilate when considering the effect of solid-liquid reaction on the liquid line of descent. INTRODUCTION linear functions of their independent variables, i.e., the enthalpy, H, is a non-linear function of tem- CHEMICAL MASSTRANSFER in magmatic systems perature, pressure and the number of moles of sys- has been simulated previously as a succession of tem components. Therefore, after deduction of the steps in temperature, pressure or bulk composition, appropriate potential, its minimum must be com- with each step characterized by heterogeneous puted by finding those particular values of the in- equilibrium (GHIORSO, 1985; GHIORSO and CAR- dependent variables of the system that satisfy the MICHAEL, 1985). This approach has made possible non-linear constraint(s). This is a formidable nu- the numerical simulation of magmatic processes merical problem, which in magmatic systems has such as equilibrium crystallization and crystal frac- only been attempted in an approximate fashion tionation. This method has also proven useful in (GHIORSO, 1985). the investigation of the assimilation of solid phases In this paper we review the theory behind the (GHIORSO and CARMICHAEL, 1985; KELEMEN and construction of potentials which are minimal in GHIORSO, 1986). However, existing computational systems subject to generalized thermodynamic techniques are inadequate for calculation of reaction constraints. This theory is rendered practical for stoichiometry in thermodynamic systems evolving computational purposes by a modification of the toward an equilibrium state under general system numerical algorithm utilized by GHIORSO (1985) constraints. By general constraints we mean those along the lines suggested by GILL et al. (1981). These other than temperature (T), pressure (P) and fixed general procedures are applied to evaluate reaction bulk composition. There are two reasons for this stoichiometry in magmatic systems evolving under inadequacy. Firstly, the Gibbs free energy, G, is not isenthalpic or isochoric constraints, or both. In ad- necessarily minimal in a thermodynamic system dition, a more rigorous treatment ofthe calculation that is generally constrained. Thus, to calculate het- of equilibria in thermodynamic systems open to a erogeneous equilibrium at each step in a mass perfectly mobile component (KORZHINSKII, 1959; transfer calculation, proceeding under a specified THOMPSON, 1970) is given. Numerical examples set of generalized constraints, requires the genera- that model assimilation in magmas under both iso- tion of a thermodynamic potential which is minimal thermal and isenthalpic conditions are provided. under these conditions. The second difficulty is These examples illustrate the utility of the technique computational. Constraints other than temperature, in predicting the effects of assimilation on derivative pressure or fixed bulk composition are usually non- liquids. 319 320 M. S. Ghiorso and P. B. Kelemen CONSTRUCTION OF THERMODYNAMIC mole numbers held constant except those of oxygen, POTENTIALS the potential 4> can be expressed as [Equation (2)]: In this section we utilize mathematical methods (3) for defining thermodynamic potentials which have been described by CALLEN (1961) and THOMPSON Potentials of the form of Equation (3), which are (1970). Let 'l1 be an unspecified thermodynamic minimal in systems open to perfectly mobile com- potential which is minimal at equilibrium. This ponents, are usually referred to as Korzhinskii po- minimum is constrained by the specification oflin- tentials (THOMPSON, 1970). ear and possibly non-linear relationships among We now utilize Equation (2) to construct a num- ber of thermodynamic potentials which are useful the independent variables of'l1. For example, if'l1 in calculating reaction paths in magmatic systems. = G(T, P, nh na, ... , nc), where nh nz to nc are variables denoting the number of moles of each of the c system components in each phase, then G is Isenthalpic constraints minimal at equilibrium subject to constant tem- We seek the potential 4>(H, P, n1, n2, ... , nc)' perature, pressure and fixed bulk composition. The From the definition of the Gibbs free energy a new latter constraint does not imply that nl through n, potential may be defined: must be held constant in the processes of minimiz- ing G, but rather that linear combinations of the nl G/T=H/T-S, (4) through nc must be constrained in order that the The total derivative of G/T may be deduced from system bulk composition remain constant. There Equation (4): will always be more n/s than compositional vari- ables in a multi-phase thermodynamic system. Mathematically, finding the minimum of G is sim- ~¥)= Hd(~) + ~dH - dS, ply a case of optimizing a non-linear function sub- and given that ject to linear equality constraints. Let the independent variables of 'l1 be denoted by x, y, nh nz, ... , nc. For convenience, we will dH= TdS+ VdP+ Lµ;dn;, ;=1 group the mol numbers of the various system com- we have: ponents to form the elements of a vector denoted by n such that: (1) Equation (5) demonstrates that aG/T)_- -H ( a I/T P,n - , Thus, we may write 'l1 = 'l1(x, y, n). If a new ther- modynamic potential, 4>, is to be defined such that which allows us to write, by using Equation (2): 4> = 4>«a'l1/ax)y,n, y, n), then 4> is given by the Le- gendre transform (CALLEN, 1961) of 'l1: G 1(aG/T) 4>(H,p,n)=y-y al/T P,n 4>((~~) ,y,n)='l1(x,y,n)-x(~~), (2) G 1 y,n y.n =---H T T As an example, we might consider the case treated by THOMPSON (1970) and GHIORSO (1985) of a 4>(H,P,n) = =S. (6) perfectly mobile component. Imagine a magmatic system whose boundaries are open to oxygen ex- Equation (6) establishes that equilibrium in a closed change such that the chemical potential of oxygen system subject to constant enthalpy and pressure is in the system is fixed by external constraints, By given by a maximum in entropy, denoting this chemical potential µ02' we seek a new potential, 4>, which is minimal at equilibrium in Isochoric constraints this partially open magmatic system at constant temperature and pressure. By recognizing that ~ In this case we seek the function 4>(T, V, n). The is defined as (aG/anO')T,p,n*, where n* denotes all formalism of the Legendre transform is unnecessary Evaluating reaction stoichiometry 321 in the case of isochoric constraints as the required such that function 4> is just the Helmholtz free energy, de- Cn-b=O noted by the symbol A: Ilx(n, T, P) = 0 4>(T,V,n)=A=G-PV. (7) and Combined isenthalpic and isochoric constraints Ily(n, T, P) = O. (10) Under conditions of constant enthalpy and vol- From examination of Equation (10) it is clear that ume the potential 4> can be obtained from Equation the calculation of heterogeneous equilibrium in (5) by recognizing that generally constrained thermodynamic systems is essentially a problem in non-linear optimization aG/T) V subject to non-linear constraints. A numerical ( ap (l/n,n T' method for the solution of Equation (10) is provided in Appendix A. from which the Legendre transform may be con- structed as: THE ADDITION OF PERFECTLY MOBILE COMPONENTS 4>(HVn)=Q_.!.(aG/T) _p(aG/T) " T T a I/T P,n ap (I/T),n The necessity of modelling phase equilibria in magmatic systems open to oxygen exchange has G 1 V =---H-P- been discussed by GHIORSO (1985), GHIORSO and T T T CARMICHAEL (19850 and CARMICHAEL and GHIORSO (1986). This need arises out of a lack of 4>(H,V,n) = -S- VP (8) knowledge regarding relevant oxidation-reduction T' couples which buffer the ferric/ferrous ratio in a Equation (8) establishes the potential which is min- crystallizing magma. For modelling purposes it is imal under conditions of constant enthalpy, volume convenient to approximate the effect of these un- and fixed bulk composition. known homogeneous redox equilibria by specifying the chemical potential of oxygen in the system. THE MATHEMATICAL PROBLEM OF GHIORSO (1985) formulated a solution to the min- MINIMIZING <) imization of the Korzhinskii potential for open sys- tem oxygen exchange by approximating the non- In order to calculate heterogeneous equilibrium linear equality constraint corresponding to fixed with the chemical mass transfer algorithm of chemical potential of oxygen in the system with an GHIORSO (1985) we require a numerical method to empirical linearized constraint.
Load more

Recommended publications
  • Syllabus of Geology
    THE UNIVERSITY OF BURDWAN Syllabus for 3-Year Degree Course in Geology (Honours) Full Marks: 800 Distribution of Papers, Marks And Lectures/Periods PART I EXAMINATION (EXAMINATION AT THE END OF FIRST YEAR) Theory Subject Marks No. of lectures Paper-I A. Crystallogroaphy (10) & Mineralogy (30) 40 80 B. Igneus Petrology- I 20 40 C. Metamorphic Petrology-I 20 40 D. Sedimentology-I 20 40 TOTAL 100 Paper-II A. Earth System Sciences 20 40 B. Structural Geology-I 20 40 C. Principles of Stratigraphy 10 20 TOTAL 50 Practical Paper-I Crystallography 05 Hand specimens of minerals 10 Hand specimens of rocks 15 Identification of minerals under microscope 10 Field Report 05 Laboratory Note Book 05 TOTAL 50 150 GRAND TOTAL 200 PART II EXAMINATION (EXAMINATION AT THE END OF SECOND YEAR) Theory Subject Marks No. of lectures Paper-III A. Igneous Petrology-II 20 40 B. Metamorphic Petrology-II 20 40 C. Geochemistry 30 60 D. Geotectonics 30 60 TOTAL 100 Paper-IV A. Structural Geology-II 20 40 B. Sedimentology-II 20 40 C. Hydrogeology 10 20 TOTAL 50 Practical Paper-II Structural Geology-I 35 Field Report 10 Laboratory Note Book 05 TOTAL 50 150 GRAND TOTAL 200 1 PART III EXAMINATION (EXAMINATION AT THE END OF THIRD YEAR) Theory Subject Marks No. of lectures Paper-V A. Principles of Palaeonotology 20 40 B. Palaeonotology 30 60 C. Indian Stratigraphy 50 100 TOTAL 100 Paper-VI A. Economic Geology 50 100 B. Fuels 20 40 C. Natural Resources Management 30 60 TOTAL 100 Practical Paper-III Petrography of Igneous rocks 15 Petrography of Metamorphic rocks 15 Special optics 15 Laboratory Note Book 05 TOTAL 50 150 Paper-IV Sedimentology 15 Remote Sensing 15 Hydrogeology 15 Laboratory Note Book 05 TOTAL 50 150 Paper-V Structural Geology-II 35 Field Report 10 Laboratory Note Book 05 TOTAL 50 150 Paper-VI Palaeonotology 45 Laboratory Note Book 05 TOTAL 50 150 GRAND TOTAL 400 2 DETAILS OF THE THREE YEAR B.Sc.
    [Show full text]
  • Introduction to Igneous Petrology
    Cambridge University Press 978-1-107-02754-1 - Essentials of Igneous and Metamorphic Petrology B. Ronald Frost and Carol D. Frost Excerpt More information Chapter 1 Introduction to Igneous Petrology 1.1 Introduction Igneous petrology is the study of magma and the rocks that solidify from magma. Th us igneous petrologists are concerned with the entire spectrum of processes that describe how magmas are produced and how they ascend through the mantle and crust, their mineralogical and geochemical evolution, and their eruption or emplacement to form igneous rocks. Igneous petrology requires a working knowledge of mineralogy. Readers who wish to review the characteristics of the major rock-forming igneous minerals will fi nd a concise sum- mary in Appendix 1. Th e appendix emphasizes the identifi cation of rock-forming minerals in hand sample and in thin section. In addition, the appendix includes descriptions of minerals found in minor abundance but commonly occurring in igneous rocks, including accessory minerals that contain trace amounts of uranium and are important geochronometers. Before geologists can understand the origin of igneous rocks, they must classify and describe them. Th is chapter introduces the classifi cation of igneous rocks using the mineralogical classifi cation system recom- mended by the International Union of Geological Sciences (IUGS) Subcommission on the Systematics of Igneous Rocks, which has the advantage that it is relatively simple and can be applied in the fi eld. For rocks that are too fi ne-grained to name using this classifi cation, a geochemical classifi cation can be employed instead. Th e simplest of these, the total alkali versus silica classifi cation, is introduced in this text.
    [Show full text]
  • Earth Sciences 3313A: IGNEOUS PETROLOGY ˗ Fall 2019
    EARTH SCIENCES 3313A – Igneous Petrology Earth Sciences 3313A: IGNEOUS PETROLOGY ˗ Fall 2019 Arenal Volcano, Costa Rica Ultramafic flow, spinifex texture, fresh and altered Instructor: Robert Linnen Office B&GS 1000B email: [email protected] tel. ext. 89207 Meeting hours: There are no fixed office hours, please set up an appointment when you need to meet Teaching Assistant: to be determined Pre-requisites: ES 2206a/b - Mineral Systems, Crystallography and Optics Schedule Lectures: Tuesdays & Thursdays: 12:30-13:20, Room: NCB-295. Labs: Thursday 2:30-5:20 and, depending on enrolment, 6:00-9:00 Room: B&GS-1065 Important Dates Tuesday, October 17th: Midterm exam in class Fall Reading Week November 4-8 no classes Thursday, November 28: Lab exam in BGS 1065 December 8 – 19: Examination period. Final exam, date and location TBA. 1 EARTH SCIENCES 3313A – Igneous Petrology CALENDAR DESCRIPTION OF EARTH SCIENCES 3313A “IGNEOUS PETROLOGY" Study of igneous processes using rock and thin section descriptions (petrography). Discussion of how different compositions and conditions influence the phases present in a rock (phase equilibria). Association of different rock types with plate tectonic setting. WHAT ARE THE PRINCIPLE OBJECTIVES OF THIS COURSE? To outline the physical and chemical properties of magma, to introduce the techniques that are used to interpret the origin and evolution of different series of magmas and to examine in more detail magma evolution in specific igneous/tectonic environments. The laboratory is an integral part of the course and students will learn to identify common igneous rocks and textures in hand specimen and in thin section using a petrographic microscope.
    [Show full text]
  • Magma Genesis, Plate Tectonics, and Chemical Differentiation of the Earth
    REVIEWS OF GEOPHYSICS, VOL. 26, NO. 3, PAGES 370-404, AUGUST 1988 Magma Genesis, Plate Tectonics, and Chemical Differentiation of the Earth PETER J. WYLLIE Division of Geolo•7icaland Planetary Sciences,California Institute of Technolo•Ty,Pasadena Magma genesis,migration, and eruption have played prominent roles in the chemical differentiation of the Earth. Plate tectonics has provided the framework of tectonic environments for different suites of igneousrocks and the dynamic mechanismsfor moving massesof rock into melting regions.Petrology is rooted in geophysics.Petrological and geophysicalprocesses are calibrated by the phase equilibria of the materials. The geochemistry of basalts and mantle xenoliths demonstrates that the mantle is hetero- geneous.The geochemical reservoirs are related to mantle convection, with interpretation of a mantle layered or stratified or peppered with blobs. Seismic tomography is beginning to reveal the density distribution of the mantle in three dimensions,and together with fluid mechanical models and interpreta- tion of the geoid, closer limits are being placed on mantle convection. Petrological cross sectionscon- structed for various tectonic environments by transferring phase boundaries for source rocks onto assumedthermal structuresprovide physical frameworks for consideration of magmatic and metasoma- tic events,with examplesbeing given for basalts,andesites, and granites at ocean-continentconvergent plate boundaries, basalts and nephelinitesfrom a thermal plume beneath Hawaii, kimberlites in cratons,
    [Show full text]
  • Geology 1 Geology Courses GEOL 1100
    Geology 1 Geology Courses GEOL 1100. Transitioning to University Studies in Geosciences. 1 Credit Hour (Lecture: 1 Hour, Lab: 1 Hour). An introduction to geosciences, including earth science, environmental science, geology, hydrogeology, and petroleum geology. Practical study designed to prepare the geoscience student for university life, aid in the development of skills for academic success, promote personal growth and responsibility, and encourage active involvement in the learning process. GEOL 1403. Physical Geology. 4 Credit Hours (Lecture: 3 Hours, Lab: 2 Hours). An introduction to the physical processes that operate in and on the planet Earth. Topics of discussion include: the Earth's structure, rocks and minerals, volcanoes, earthquakes, groundwater, rivers, glaciers, and deserts. Lab fee: $2. GEOL 1404. Historical Geology. 4 Credit Hours (Lecture: 3 Hours, Lab: 2 Hours). History of the Earth from the formation of the solar system to the present. Topics include the Earth's development, evolution of life on Earth, changes in the Earth's geography throughout its history, and the tools geologists use to investigate these topics. Lab fee $10. GEOL 1407. Introduction to Environmental Science. 4 Credit Hours (Lecture: 3 Hours, Lab: 2 Hours). Introduction to the study of the environment. The course will examine air, water, and soil pollution, and pollution remediation. Energy, mineral resources, and land use will be studied. The course will also emphasize a study of the water supply, water use, and water management. Much of the laboratory will focus on land use planning and environmental pollution remediation. Lab fee: $2. GEOL 1408. Natural Disasters. 4 Credit Hours (Lecture: 3 Hours, Lab: 2 Hours).
    [Show full text]
  • PG 2Nd Semester Paper: GLG801C (Core) Igneous Petrology L+T+P=3+1+0= 4 Credits
    PG 2nd Semester Paper: GLG801C (Core) Igneous Petrology L+T+P=3+1+0= 4 credits Total Number of Theory classes (Lectures) : 48 (48 hours) Total Number of Tutorial classes (Tutorials) : 16 (16 hours) THEORY Igneous Petrology : Number of Lectures: 48 Magma: Composition, physical properties and origin; Magmatic crystallisation, differentiation and assimilation; Nucleation and growth; Interpretation of common igneous textures with respect to nucleation and crystal growth; Role of partial melting in igneous petrogenesis The phase equilibrium of binary and ternary systems and their relation to magma genesis and crystallization in the light of modern experimental works; Classification of igneous rocksconcept of mode and norm Plate tectonics and generation of magmas in different tectonic settings; Igneous rocks in different tectonic settings: mid-oceanic ridge, oceanic intraplate, subduction and continental rift related settings; Geochemical characteristics of igneous rocks: major, trace and isotopic composition of igneous rocks in the context of petrogenesis; Compatible and incompatible trace elements; Application of trace elements in petrogenesis and source characterization; Geochemical criteria for identification of palaeotectonic settings; Mobility of elements during post-crystallization processes Petrology and petrogenesis of the following igneous rocks with suitable Indian examples: (i) Komatiites, anorthosites and ophiolites (ii) Large igneous provinces, boninites and layered complexes (iii) Alkaline rocks, carbonatites, kimberlites and lamprophyres (iv) Adakites and sanukitoids Recommended Books: 1. Best, M.G., 2002. Igneous Petrology, 2nd Edition, Blackwell Publishers 2. Bose, M.K., 1997. Igneous Petrology, World Press, Kolkata. 3. Hall, A., 1997. Igneous Petrology, Longman. 4. Phillpotts, A.R., 1994. Principles of Igneous and Metamorphic Petrology, Prentice Hall of India. 5.
    [Show full text]
  • Igneous Petrology 2001
    MetamorphicMetamorphic PetrologyPetrology LectureLecture 1:1: MetamorphicMetamorphic phenomenaphenomena andand theirtheir characterization:characterization: AnAn introductionintroduction byby StephanStephan KK MatthäiMatthäi MP-SKM, slide 1 Course Objectives I will try to teach you: • To identify common metamorphic rocks in the field and infer their protoliths (original rock types and composition), • Understand how they formed, • Get broad estimates of the pressure and temperature conditions under which the rocks were metamorphosed, • How to use overprinting relationships and deformation structures to determine the geological / metamorphic history of the rocks, • Infer the burial depth and thermal history of the metamorphic pile, • Make PTt-path diagrams • Interpret the plate-tectonic setting of metamorphism, • Quantify the chemical changes that the rock underwent during metamorphism (gains & losses), Get you ready for independent field work. MP-SKM, slide 2 ES4.08 Prerequisites Geology: plate-tectonic settings, basics of sedimentary and igneous rocks, magmatism and volcanism (Internal Processes, Dynamic Earth) Mineralogy: ability to determine the main rock-forming minerals in hand specimen and thin section; ideally, a knowledge of the chemical composition of minerals (Minerals & Rocks, Optical Mineralogy & Petrography) Chemistry: stochiometry (balancing reactions), possible valency states of cations, law of mass action, equilibrium constants (Geochemistry 1) Thermodynamics: absolute basics – Gibbs free energy, heat capacity, entropy,
    [Show full text]
  • Igneous Petrology
    IGNEOUS PETROLOGY PRESENTED BY Dr.A.BALUKKARASU Associate Professor Centre for Remote Sensing Bharathidasan University Thiruchirappalli-620 023 India. mail id:[email protected] MTIGT0403: IGNEOUS & METAMORPHIC PETROLOGY 1. Forms and Structures of Igneous rocks - Intrusives and their relation to Geological Structures (Concordant and Discordant forms - Multiple Intrusions – Composite Intrusions) - Composition and Constitution of Magmas - Structure and Texture of Igneous Rocks- Formation of Igneous rocks: Crystallization of Unicomponent Magma -Phase Equilibria studies of Binary and Ternary Silicate system - Crystallisation of Basaltic magma. 12 Hrs. 2. Classification of Igneous rocks – Microtextures and Structures of Igneous rocks and their Petrogenetic Significance - Petrography of Igneous rocks – Tabular Classification - Petrography of Acid-Intermediate - Basic and Ultrabasic rocks - Diversity of Igneous rocks - Reaction Principle - Magmatic Crystallization – Assimilation – Petrographic province and various diagrams - Plate Tectonics and Magmatic Evolution – Fluid Inclusion studies of Igneous rocks. Evolution of Basalts -Petrogenesis of Granites, Pegmatities, Alkaline rocks, Monomineralic rocks, Charnockites and Ultramafics. 14 Hrs. 3. Definition of Metamorphism - Scope of Metamorphism – Controlling factors of Metamorphism - Kinds of Metamorphism and its Products - Classification and Nomenclature - Petrography of Metamorphic rocks (Schists – Gneisses – Granulites) - Metamorphic textures and Microstructures and their relation to Metamorphic
    [Show full text]
  • Jacqueline-Vander-Auwera.Pdf
    Jacqueline Vander Auwera Earth & Environment ︱ The types of boundaries between tectonic plates help to describe how the different types of crust move in relation to each other across Earth’s surface. At convergent boundaries, two tectonic plates push against each other. The denser plate will Magma differentiation begin to subduct or sink into the mantle below. Where an oceanic plate meets The complex processes behind active volcanism a continental plate, the denser oceanic plate will sink below the continental plate, creating a subduction zone. Active volcanism is prevalent olcanoes and earthquakes are the of igneous rock samples from volcanic across much of the Earth’s most obvious sign that the Earth eruptions in order to understand the VOLCANOES AND is a dynamic, geologically active geochemical processes within the surface, yet the deep mantle V PLATE TECTONICS Cerro La Picada, Chile. and crustal processes planet. They are a visible representation magma prior to its eruption. Professor Vander Auwera is particularly Left: as seen from Putrehue river. that drive it are still being of plate tectonics: the slow movement interested in volcanoes that form above understood by geologists. of the Earth’s outermost, brittle layer. WHAT ARE PLATE TECTONICS? subduction zones, such as the Andean Untangling the complex The exact mechanism for how and why The Earth is divided into layers, which Arc in South America. This volcanic belt chemical relationships these plates move is still hotly debated differ in both physical and chemical runs down the western edge of the South Geochemists untangle complex chemical that arise from magma by geologists.
    [Show full text]
  • 316 Syllabus Spring
    Petrologic Systems - 316L Spring, 2020 Instructors: Scott Paterson, ZHS 307, 740-6103, [email protected], office hours: TBA. John Platt, ZHS 313, 821-1194; [email protected], office hours: TBA. Teaching assistant: Cullen Scheland, ZHS-309; email [email protected]. Time and Place Lecture: Tuesdays, Thursdays 1:00PM – 2:20PM at ZHS118 Lab: Th, 2:30PM – 4:20PM, ZHS B65 Textbook: Principles of Igneous and Metamorphic Petrology (2nd edition) John Winter. Prentice Hall, 2009. Exams: Exam 1 (Igneous midterm) – March 5, 2.30-4:20 pm Exam 2 (Metamorphic midterm) – Thursday April 30, 2.30-4:20 pm Field Trips: Igneous Rocks: Feb. 21-23, Peninsular Ranges Batholith, we will leave at 9 am. Metamorphic Rocks: April 9-12, Santa Catalina Island. Basis of Grade: Lecture midterms: (total 50%): Igneous Midterm 25 % Metamorphic Midterm 25 % Lab (total 50%): Lab assignments 30% Field trip projects (total 20%): Igneous paper on arcs, 10% Metamorphic paper on Catalina 10% Schedule of Lectures Jan. 14: Class Intro (Reading: Chapter 1) Go over course and syllabus. Differentiation of solar system+earth, crustal growth, heat sources, and plate tectonics Igneous Petrology Module Jan. 16: Magmatism and tectonics, (Readings: Chapters 1, 13-20) Sources and styles of magmatism at different plate boundaries Sources and styles of magmatism at intraplate settings Jan. 21: Transcrustal magmatic-volcanic systems (Reading: Chapters 4, 16, 17) Jan. 23: Introduction to igneous rocks (Reading: Chapters 2, 3, 18) Review of common rock types and rocks as assemblages of minerals. Modal and chemical compositions of rocks, common types of variation diagram. Jan. 28-30: Properties and classifications of igneous rocks, (Readings: Chapter 2, 3, Appendix B) Information about magmatic processes preserved by textures: Textural based classifications Quartzofeldspathic, mafic, ultramafic rock classifications Feb 4: Mantle melts (Readings: Chapter 10) Feb.
    [Show full text]
  • Geology Course Guidelines
    North Carolina Geological Licensure: Academic Guidelines Geology license applicants are required to have completed at least 30 semester hours of geoscience or geoscience-related courses that include 24 hours of advanced courses and that lead to a degree in geosciences as described below. (A) Significant course content (required) “leading to a degree” in geology/geosciences Lower level courses • physical/general geology • geologic time - e.g. historical geology or Earth history Advanced courses • mineralogy • igneous petrology • metamorphic petrology • sedimentology/stratigraphy • structural geology Most or all of the above will have associated, required labs. Some schools, such as North Carolina State University (NCSU), have a course in Intro to Mineralogy & Petrology (MEA 410) that includes significant content in mineralogy, igneous petrology, and metamorphic petrology, which would fulfill the licensing academic requirement for those three categories. Other universities would require separate semester courses in each or might combine them in a different way. Although most physical geology courses introduce mineral identification and igneous/metamorphic/sedimentary petrology, the fundamental content would fulfill only the general geology (lower level) requirement. Thus, if a student followed the course sequence for the NCSU Geology (BS) degree, the following courses (and their prerequisites) would be required for licensure: Lower level courses Geology I: Physical MEA 101 Geology I lab MEA 110 Geology II: Historical MEA 202 Geology II lab MEA 211 Advanced courses Intro to Mineralogy & Petrology MEA 410 Sedimentary Petrol. & Stratigraphy MEA 450 Structural Geology MEA 451 The lower level courses total 8 hours and the advanced courses total 12, so s/he would need to take additional advanced courses that total at least 12 more semester hours that, all told, would lead to a geology or geosciences degree.
    [Show full text]
  • Contributions to Mineralogy and Petrology 1995 Ghiorso.Pdf
    Contrib Mineral Petrol (1995) 119:197-212 , 9 Springer-Verlag 1995 Mark S. Ghiorso 9Richard O. Sack Chemical mass transfer in magmatic processes IV. A revised and internally consistent thermodynamic model for the interpolation and extrapolation of liquid-solid equilibria in magmatic systems at elevated temperatures and pressures Received: 1 February 1994 / Accepted: 26 August 1994 Abstract A revised regular solution-type thermodyn- systems open to oxygen are detcrmined by directly amic model for twelve-component silicate liquids in the specifying the/o2 or the T-P-fo~ (or equivalently H-P-f;~, system SiOa-TiO2 A1203-Fe203-Cr203-FeO MgO S-P-fo2, T-V-L) evolution path. Calculations are per- CaO-Na20-K20 P2Os-H20 is calibrated. The formed by constrained minimization of the appropriate model is referenced to previously published standard thermodynamic potential. Compositions and propor- state thermodynamic properties and is derived from tions of solids and liquids in the equilibrium assem- a set of internally consistent thermodynamic models for blage are computed. solid solutions of the igneous rock forming minerals, including: (Mg, Fe 2 +, Ca)-olivines, (Na, Mg, Fe 2 +, Ca) M2 (Mg, Fe 2+, Ti, Fe 3+, A1)M1 (Fe 3+, A1, Si)2T~a'O6- Introduction and motivation pyroxenes, (Na,Ca,K)-feldspars, (Mg, Fe 2 +) (Fe 3 +, A1, Cr)20r Fe2+)2 TiO4 spinels and (Fe2+,Mg, In this paper, we present a substantial revision of the Mn 2 ~-)TiO3-Fe203 rhombohedral oxides. The calib- thermodynamic model of Ghiorso et al. (1983) and ration utilizes over 2,500 experimentally determined announce new computer software for the calculation of compositions of silicate liquids coexisting at known chemical mass transfer in magmatic systems (e.g.
    [Show full text]