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Table of Contents TABLE OF CONTENTS FOREWORD and EDITOR'S PREFACE AND ACKNOWLEDGMENTS (iii) USEFUL REFERENCES (ix) Chapter 1. The CRYSTAL CHEMISTRY and STRUCTURE of OXIDE MINERALS as EXEMPLIFIED by the Fe-Ti OXIDES Donald H. Lindsley INTRODUCTION L- 1 Techniques L- 1 Magnetic properties L- 2 THE CUBIC OXIDE MINERALS L- 4 Monoxides (Space group Fm3m) L- 5 Spinel group L- 7 Magnetite (Fes04> L-12 UlvSspinel (FegTiOg) L-15 Magnetite-ulv'ôspinel solid solutions L-15 Maghemite (y-Fe20s) L-18 Magnetite-maghemite solid solutions L-22 THE RHOMBOHEDRATitanomaghemitesL OXIDE S L-3L-214 Hematite L-34 Magnetic structure of hematite L-36 Curiej Nêel, and Morin temperatures of hematite L-37 Ilmenite L-38 Crystal structure of ilmenite L-38 Magnetic structure of ilmenite L-40 Crystal and magnetic structure of hematite-ilmenite solid solutions L-41 ORTHORHOMBIC OXIDES—THE PSEUDOBROOKITE GROUP L-44 The structure of pseudobrookite (Fe2Ti05) L-45 The Fe2Ti05-FeTi205 series L-45 STRUCTURES OF RUTILE, ANATASE, AND BROOKITE L-47 REFERENCES L-52 Chapter 2. EXPERIMENTAL STUDIES of OXIDE MINERALS Donald H. Lindsley INTRODUCTION L-61 Control of experimental conditions L-61 Oxygen fugacity L-62 Container problems L-64 Experiments at very high pressures or high temperatures L-64 Minerals and phases considered L-65 FE-TI-0 SYSTEM Fe-0 join L_66 Wustite L~67 Fe20s in magnetite L-67 L~67 Fe0-Ti02 join L_68 Fe2Û3-Ti02 join u (iv) Fe0-Fe203-Ti02(-Ti203) join L-69 1300°C isotherm L-69 Ti-Maghemite L-75 Reduction of Fe-Ti oxides L-75 FE-0-MG0-TI02 SYSTEM L-79 Fe0-Fe203-Mg0 join L-80 Fe0-Mg0-Ti02(-Ti203) join L-80 Fe0-Fe203-Mg0-Ti02 join L-81 FE0-FE203-AL203 SYSTEM L-81 CR203-BEARING SYSTEMS L-82 Fe0-Fe203-Cr203 system L-82 MgAl20^-Mg2Ti0^-MgCr20^ system L-83 FeCr204-Fe304-FeAl20^ system L-84 REFERENCES L-84 Chapter 3. OXIDE MINERALS in METAMORPHIC ROCKS Douglas Rumble, III INTRODUCTION R- 1 MINERALOGY R- 1 Spinel solid solutions R- 1 Hematite-ilmenite solid solutions R- 3 Pseudobrookite solid solutions R- 6 Rutile and polymorphs R- 6 OXIDE MINERALS IN RELATION TO METAMORPHIC MINERAL ZONES R- 7 Metamorphic zones of low to intermediate pressure R- 9 ChXorite and biotite zones R- 9 Garnet and staurolite zones R- 9 Sillimanite zone R-10 Sillimanite-potash feldspar zone R-10 Chromian spinel composition in relation to metamorphic zones . R-10 High-temperature contact metamorphism R-ll High-pressure metamorphism R-ll PHASE PETROLOGY R-ll Element partitioning R-ll Oxide mineral equilibria R-12 Oxide-silicate mineral equilibria R-15 Deduction of conditions of metamorphism R-16 OXIDATION-REDUCTION PROCESSES IN METAMORPHISM R-19 REFERENCES R-20 Chapter 4. OXIDATION of OPAQUE MINERAL OXIDES in BASALTS Stephen E. Haggerty INTRODUCTION Hg- 1 OXIDATION PARAGENESIS Hg- 3 Primary oxide mineralogy Hg- 3 Oxidation of ulvbspinel-magnetite solid solutions Hg- 4 Trellis type Hg- 4 Composite types Hg- 8 (v) Sanduich type Hg-16 Oxidation of titanomagnetite-ilmenite intergrowths Hg-16 C4 stage Hg-17 C5 stage Hg-20 C6 stage Hg-21 C7 stage Hg-24 Oxidation of discrete primary ilmenite Hg-28 Ilmenite oxidation classification Hg-28 PHASE CHEMISTRY OF OXIDATION ASSEMBLAGES Hg-37 Introduction Hg-37 Titanomagnetite-ilmenite assemblages Hg-46 Ferrian ilmenite and ferrian rutile Hg-49 Titanohematite, rutile, and magnetite Hg-50 Pseudobrookite, titanohematite, magnetite and Al-magnesioferrite Hg-52 OXIDE SYSTEMATICS AND PHASE COMPATIBILITY RELATIONSHIPS Hg-55 Introduction Hg-55 Ilmenite systematics Hg-61 Titanomagnetite systematics Hg-61 Applications Hg-69 ASSOCIATED MINERAL OXIDATION Hg-74 Introduction Hg-74 Chromian spinel oxidation Hg-74 Olivine oxidation Hg-75 OXIDE DISTRIBUTIONS IN BASALT PROFILES Hg-78 Introduction Hg-78 Mean oxidation numbers Hg-79 Oxide distributions Hg-82 Mechanism of oxidation Hg-94 IMPLICATIONS FOR ROCK MAGNETISM AND OXIDE PETROGENESIS Hg-95 Introduction Hg-95 Oxidation Hg-96 Single cooling units Hg-98 SUMMARY AND CONCLUSIONS Hg-98 Chapter 5. OXIDE MINERALS in LUNAR ROCKS Ahmed El Goresy INTRODUCTION EG- 1 MINERALOGY EG- 1 Chromite-ulv8spinel series EG- 1 Ilmenite-geikielite series EG- 3 Armalcolite-anosovite series EG- 4 Rutile EG- 4 OXIDE RELATIONS IN DIFFERENT ROCK TYPES RECOVERED FROM THE MOON . EG- 4 Opaque oxides in Ti02~poor basalts EG- 4 Spinels EG- 5 Cationic relationships and substitutions EG-14 Cr-Al substitutional trends EG-14 V-Cr and V-Al substitutional trends EG-17 (vi) Fe-Mg substitutional trends EG-19 Ti-(V+Cr+Al) substitutions EG-19 Opaque oxides in Ti02-rich basalts EG-24 Armaloolite relationships EG-24 Origin of ilmenite rims around armaloolite in olivine porphyritio basalts EG-25 Chemistry of armaloolite EG-30 Chromian ulv'dspinel EG-34 Ilmenite EG-35 Rutile EG-3 6 Opaque oxides in anorthositic rocks and highland breccias .... EG-36 Spinels EG-3 7 Ilmenite EG-37 Rutile EG-37 SUBSOLIDUS REACTIONS EG-38 Subsolidus reduction reactions in the lunar rocks EG-39 Nature of reducing agent in Apollo 17 basalts EG-42 REFERENCES EG-43 Chapter 6. OPAQUE OXIDE MINERALS in METEORITES Ahmed El Goresy INTRODUCTION EG-47 MINERALOGY EG-49 Spinel group minerals EG-49 Ilmenite-geikielite-pyrophanite series EG—56 Rutile EG-5 7 OXIDE ASSEMBLAGES IN VARIOUS METEORITE GROUPS EG-57 Chondrites EG-57 Spinels EG-5 9 Ilmenite EG-6 2 Achondrites EG-64 Ilmenite EG-6 5 Stony irons EG-65 Iron meteorites EG-67 REFERENCES EG-71 Chapter 7. The MANGANESE OXIDES - A BIBLIOGRAPHIC COMMENTARY J. Stephen Huebner INTRODUCTION SH- 1 Crystal structures and chemistry SH- 1 Tetravalent oxides SH- 1 Trivalent oxides SH- 2 "Spinel-type" oxides SH- 3 WUstite-type oxide SH- 4 Geologic occurrences SH- 4 Thermochemistry and phase relations SH- 6 Petrology of manganese oxides SH- 8 REFERENCES SH-11 (vii) Chapter 8. OPAQUE MINERAL OXIDES in TERRESTRIAL IGNEOUS ROCKS Stephen E. Haggerty GENERAL INTRODUCTION Hg-101 SYSTEMATIC MINERALOGY Hg-101 Nomenclature Hg-101 Spinel series Hg-101 Ilmenite series Hg-104 Pseudobrookite series Hg-104 TiOg polymorphs Hg-104 Exsolution Hg-104 Subsolidus reactions Hg-108 Oxide assemblages and textures Hg-108 Two-dimensional mineral morphology Hg-108 Chromian spinelss Hg-109 Ilmenite-hematitess Hg-118 Reactions involving ilmenite-hematitess Hg-119 UlvOspinel-magnetitess Hg-123 Titanomagnetite-pleonaste^s Hg-128 Magnetite-chronrite-hercymtess Hg-129 Reactions involving magnetite-ulvSspinelss Hg-129 Oxides derived from silicates Hg-135 PRIMARY OXIDE DISTRIBUTIONS Hg-140 Introduction Hg-140 Chromian spinel distributions Hg-142 Pseudobrookite distributions Hg-150 Ilmenite distributions Hg-152 Magnetite-ulvSspinel distributions Hg-158 Oxidites Hg-158 T AND fo2 VARIATIONS IN IGNEOUS ROCKS Hg-160 Introduction Hg-160 Extrusive suites Hg-160 Intrusive suites Hg-160 Magmatic ore deposits Hg-167 Data summary Hg-167 Experimental determinations of T and fQ2 Hg-169 Silica activity Hg-169 TABLES OF MINERALOGICAL, PETROLOGICAL, AND CHEMICAL PROPERTIES OF OPAQUE MINERAL OXIDES IN IGNEOUS ROCKS Hg-176 REFERENCES Hg-277 (viii) .
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