Popigai Impact Structure and its Diamond-Bearing Rocks

INTRODUCTION<br> <p>CHAPTER 1. MAIN GEOLOGICAL FEATURES OF IMPACT CRATER AND ITS ENVIRONMENT</p> <p>1.1. Crystalline basement</p> <p>1.2. Platform cover</p> <p>1.3. Topography of the hollow and its surroundings</p> <p>1.4. Gravity and magnetic fields</p> <p>1.5. Morphology and inner geological structure </p> <p>1.6. Subdivision of impact lithological units and impact rocks</p> 1.7. Crater age<p></p> <p>CHAPTER 2. CONCENTRIC STRUCTURAL ZONES AND ITS IMPACT BRECCIA AND IMPACTITES </p> <p>2.1. Outer zone of sin-impact deformations and outer slope of the ring trough</p> <p>2.1.1. Area of the Sogdoku Upland</p> <p>2.1.2. Area of the middle course of the Chordy-Daldyn River</p> <p>2.1.3. Area of the up-stream of the Tongulakh River</p> <p>2.1.4. Area of the up-stream of the&nbsp; Arylakh-Yurjage River</p> &lt; <p>2.2. Ring trough and ring uplift (peak ring)</p> <p>2.2.1. Area of the up-stream and middle courses of the Balagan-Yurjage River</p> <p>2.2.2. Area of the Majachica Upland</p> <p>2.3. Central depression. Area of the lower course of Daldyn River</p> <p>2.4. Post-impact&nbsp;&nbsp; deformations</p> <p>CHAPTER 3.&nbsp; SHOCK-METAMORPHOSED CRYSTALLINE ROCKS, IMPACT BRECCIAS&nbsp; AND IMPACTITES</p> 3.1. Crystalline target rocks and their shock metamorphic features<p></p> <p>3.1.1. Brief characteristic of gneisses and plagiogneisses</p> <p>3.1.2. Mineralogical criterions&nbsp;&nbsp; of the shock metamorphic parameters</p> <p>3.1.3. Weakly and moderately shock-metamorphosed rocks</p> <p>3.1.4. Intensely&nbsp; shock-metamorphosed&nbsp; rocks</p> <p>3.1.5. Very intensely&nbsp; shock-metamorphosed&nbsp; rocks</p> <p>3.2. Impact lithic breccias </p> <p>3.2.1. Autochtonous and paraautochtonous lithic breccia</p> <p>3.2.3. Allochtonous lithic breccia</p> <p>3.2.3.1. Mega- and mesobreccia</p> <p>3.2.3.2. Microbreccia (coptoclastite)</p> <p>3.3. Tagamites</p> <p>3.3.1. Composition, texture and principles of subdivision</p> <p>3.3.2. Low-temperature tagamites (LT)</p> <p>3.3.3. High-temperature tagamites (HT)</p> <p>3.4. Suevites</p> <p>3.4.1. Composition, texture, and principles of subdivision</p> <p>3.4.2. Suevites, enriched by epiclasts</p> <p>3.4.3. Suevites, enriched by vitroclasts</p> <p>3.4.4. Impact glasses from suevites and coptoclastites</p> <p>3.5. Hydrothermal alterations of impact breccias and impactites</p> <p>CHAPTER 4. PETROCHEMISTRY AND GEOCHEMISTRY&nbsp; OF IMPACTITES AND TARGET ROCKS</p> <p>4.1. Petrochemistry and geochemistry</p> <p>4.2. Isotopic composition</p> <p>4.3. Geochemical evidence of impactor’s matter</p> <p>CHAPTER 5. IMPACT DIAMONDS FROM SHOCKED CRYSTALLINE ROCKS AND IMPACTITES</p> <p>5.1. Morphology of diamond paramorphs </p> <p>5.2. Phase composition and microtexture</p> <p>5.3. Physical properties</p> <p>5.4. Isotopic composition</p> <p>CHAPTER 6. GENERAL PATTERNS&nbsp; OF IMPACT DIAMOND DISTRIBUTION &nbsp;</p> <p>6.1. General characteristics on sampling</p> <p>6.2. Distribution of impact diamonds&nbsp; over the impact structure</p> <p>6.3. Impact diamond content and composition of host rocks</p> <p>6.4. Distribution of impact diamonds in sheet-like tagamite bodies</p> <p>6.5. Impact diamonds in placers</p> <p>6.6. Deposits of impact diamonds and their resources</p> <p>CHAPTER 7. ORIGIN OF DIAMOND-BEARING&nbsp; IMPACTITES</p> <p>7.1. Reconstruction of the impact event</p> 7.2. Main features of evolution of impact melt-forming and rock-forming petrological systems<p></p> <p>7.2.1. Initial petrological systems</p> <p>7.2.2. Transitional petrological systems</p> <p>7.2.3. Final petrological systems</p> <p>CONCLUSION</p> <p>REFERENCES</p>