I Introduction to the Earth Geology 1/85 ОСНОВНЫЕ

I Introduction to the Earth Geology 1/85

ОСНОВНЫЕ ЗАДАЧИ ГЛАВЫ Уметь назвать и описать строение и главные компоненты планеты Земля Охарактеризовать роль тектонических процессов в формировании осадочных бассейнов Изучить главные различия между магматическими, метаморфическими и осадочными породами Рассмотреть главные периоды геологического времени и связать основные геологические события Земли в масштабе геохронологической шкалы Научиться определять и описывать типы горных пород 2/85

КЛЮЧЕВЫЕ МОМЕНТЫ Понимать и описывать круговорот углерода в природе Знать основные отличия между магматическими, метаморфическими и осадочными породами Знать шкалу Мооса по твердости Классификация осадочных пород Глобальная тектоническая деятельность, связанная с плитами Представлять главные периоды геологического времени и основные события с ними связанные Понимать разницу между согласным и несогласным залеганием пород Описывать стратиграфическую последовательность напластований Закон Вальтера Знать генезис основных типов пород 3/85

Day 1 Earth structure Rocks & Minerals Plate tectonics and Sedimentary Basins Principles of Stratigraphy 4/85

endogenous processes exogenous processes Nature and composition of the Earth 5/85

James Hutton (1726-1797) James Hutton was a Scottish geologist, physician and doctor. He originated the theory of uniformitarianism —a fundamental principle of geology—which explains the features of the Earth's crust by means of natural processes over geologic time. 6/85

(Law of uniform change) «Взгляни на Природу во всех ее проявлениях. Изменение – это великий закон Природы.» Роберт Бернс «... Нет ни следов начала, ни признаков конца.....» Джеймс Геттон chemical process biological process physical process 7/85

Formation and evolution of the Solar System By: Dr. John Smetanka Posted Mon., February 11, 2013 8/85

Inner Core Outer Core Lower Mantle 82 % V Transition zone (Crust / Lithosphere) constitution of earth Size of Earth: Radius = 6370 km Diameter = 12,740 km 6370 км 2900 км 30 км 9/85

constitution of earth 10/85

Most Common Elements Oxygen Silicon Aluminum Iron Calcium Magnesium Sodium Potassium Percentage by Weight 11/85

Geological time age of the Earth 4,500,000,000 years How do we know that? - relative age; - absolute age (half-life radioactive of elements ) 12/85

Geological Time ancients rocks - 3,8 billion years meteorite - 4,55 billion years moon rocks - 4,7 billion years solar system - 5 billion years 13/85

Relative Time ● Steno`s Principles (Law of Superposition) ● Facies substitution ● Law of Faunal and Floral Succession ● Principle of included fragments 14/85

Absolute time is sometimes also called "numerical time". It dates durations of events in terms of seconds, years, millions of years, etc. Absolute Time Various techniques are applied to determine absolute time. Radiometric dating: Through the discovery of radioactivity the rate of decay (breakdown of radioactive elements) can be used to date minerals and rocks. Magnetostratigraphy: This is the use of magnetized rocks to determine the history of events in record of changes in earth's magnetic field during the past geologic ages. 15/85

Atoms of uranium, radium and several other radioactive materials are unstable and disintegrate spontaneously and consistently forming atoms of different elements and emitting radiation, a form of energy in the process. The original atom is referred to as the parent and the following decay products are referred to as the daughter. . Radiometric Dating Major radioactive elements used for radiometric dating. Absolute Time 16/85

С-14 — изотоп углерода, в ядре которого находится 6 протонов и 8 нейтронов. Этот изотоп немного тяжелее нормального углерода (С-12, в ядре которого 6 нейтронов) и участвует в тех же химических реакциях, что и С-12. С-14 образуется высоко в атмосфере при столкновении космических лучей с ядрами азота. Когда он достигает поверхности, его поглощают растения, а затем — животные, поедающие эти растения. Таким образом С-14 попадает в ткани растений и животных. В живых организмах содержатся миллионы атомов углерода, и примерно каждый миллионный — это атом С-14. С-14 нестабилен, период его полураспада — 5700 лет. Пока организм жив, любой распавшийся атом С-14 замещается таким же атомом С-14 из окружающей среды. После смерти живого существа круговорот С завершается и начинается неотвратимый распад изотопа. Метод радиометрического датирования (середина ХХ в. Чикагский у-т ) был впервые применен на практике, в качестве изотопа использовался углерод-14. 17/85

The Carbon Cycle 18/85

The Carbon Cycle 19/85

Minerals and rocks 20/85

Difference between minerals and rocks A rock is aggregate of grains or crystals of one or more minerals or a body of undifferentiated mineral matter (obsidian) or organic matter (coal) Mineral is a naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal form and physical properties 21/85

● Atoms ● Structural components ● Mineral ● Textural components ● Rock ● Outcrop 22/85

Different minerals Quartz SiO2 Calcite CaCO3 Dolomite CaMg(CO3)2 Halite NaCl Feldspar NaAlSi3O8 Pyrite FeS2 Kaolinite Al2Si2O5(OH)4 Chlorite (Mg,Fe,Al)6(Si,AL)4O10(OH)8 Illite K1-1.5Al4(Si7-6,5Al1-1.5 O20)9OH)4 Smectite (0.5Ca,Na)0.7(Al,Mg,Fe)4[Si,Al8O20](OH)4 nH2O Mica KAl2(AlSi3O10)(OH,F)2 23/85

Clay minerals Illite Smectite Kaolinite Chlorite 24/85

Important Clay Minerals Chlorite 25/85

Kaolinite 26/85

Chlorite 27/85

Permeability decreases porosity decreases Illite 28/85

Smectit 29/85

Scanning Electron Microscope Study Jim Buckman Heriot-Watt Institute of Petroleum Engineering 30/85

Kaolinite Quartz overgrowth 31/85

Etched Feldspar 32/85

Etched Feldspar 33/85

Coal 34/85

The distribution of dolomite crystals within the pore space 35/85

silicate - 25 % oxide and hydroxide - 12 % sulphide - 13 % phosphates arsenas - 18 % vanadate 36/85

Recognizing/Identifying Minerals Physical / Chemical Properties Naked eye Colour, crystal shape, Mohs’ scale of hardness Thin section Scanning Electron Microscope (SEM) X-Ray diffraction (Taste) - a type of chemical analysis! 37/85

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Характерные типы кристаллов Кубическая (галит, галенит) Тетрагональная (циркон) Гексагональная (кварц) Моноклинная (ортоклаз) Триклинная (плагиоклаз) Ромбическая (оливин) 39/85

SEDIMENTARY IGNEOUS METAMORPHIC Molten materials in deep crust and upper mantle Crystallization (Solidification of melt) Weathering and erosion of rocks exposed at surface Sedimentation, burial and lithification Rocks under high temperatures and pressures in deep crust Recrystallization due to heat, pressure, or chemically active fluids Classification of Rocks 40/85

Rock Cycle Uplift, Weathering Deposition, burial Heat (and deformation) Heating Moves in molten state Transport Lithification Intermediate products Key process 41/85

Igneous rocks are formed from the solidification of molten rock material. Igneous rocks Magma is a molten and semi-molten rock mixture found under the surface of the Earth. Magma is extremely hot—between 700° and 1,300° Celsius (1,292° and 2,372° Fahrenheit). 42/85

Igneous rocks solidify (crystallize) from molten material (magma) 43/85

Lava rock – small crystals and gas holes (volcanic) Deep intrusions – large crystals (slower cooling) eg. Granite (plutonic) Up to 10 km Below surface 44/85

Intrusive igneous rocks cool slowly, because there is less temperature difference between them and the surrounding rocks at depth, and they therefore have coarser crystals that are easy to see. Example: diorite, gabbro, granite Intrusive igneous rocks Pegmatite is a light-colored, extremely coarse-grained intrusive igneous rock. Diorite is a coarse-grained, intrusive igneous rock that contains a mixture of feldspar, pyroxene, hornblende and sometimes quartz. 45/85

Packing of grains Granite is a coarse-grained, light colored, intrusive igneous rock that contains mainly quartz and feldspar minerals. 46/85

Gabbro is a coarse-grained, dark colored, intrusive igneous rock that contains feldspar, augite and sometimes olivine. The specimen shown above is about two inches (five centimeters) across. 47/85

Type of intrusive rocks 48/85

EXTRUSIVE IGNEOUS ROCKS Extrusive igneous rocks cool relatively fast as they are extruded, and so have fine crystal sizes, often too fine to see individual crystals with the naked eye. Extrusive rocks often contain gas bubbles and include lavas (e.g. basalt, andesite, rhyolite) and tuffs (ash deposits). basalt tuffs 49/85

EXAMPLE OF EXTRUSIVE IGNEOUS ROCKS Rhyolite porphyry or porphyritic rhyolite. Andesite porphyry or porphyritic andesite (porphyritic-aphanitic). 50/85

Vesicular basalt EXAMPLE OF EXTRUSIVE IGNEOUS ROCKS 51/85

Sedimentary rocks are formed by the accumulation of particles, followed by burial, compaction and cementation of those particles. Sedimentary rocks 52/85

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Type of sedimentary rocks Chemical rocks Organic rocks Clastic rocks 54/85

Sedimentation - a natural process, which depends on the dynamic and climatic factors hypergenesis (the stage of preparing the substances) sedimentogenesis (stage sedimentation) diagenesis katagenesis metagenesis 55/85

Schematic representation 56/85

Description of sedimentary rocks Colour Texture Structure Porosity and permeability Sedimentary environment 57/85

KEY FEATURES OF ROCKS ТЕКСТУРА (Structure) Grain size Grain sorting Packing Sediment fabric Grain morphology Grain surface texture The structure of the rock , reflecting the spatial and relative position of the components and shape of rock formed by them form different scale CТРУКТУРА (Texture) 58/85

● Grain size 59/85

● Grain size 60/85

Классификация грубообломочных осадков и осадочных пород 61/85

Breccias Mega-Breccia, Death Valley, CA Clast-supported, point-to-point contact 62/85

Breccias – Angular clasts Mud-supported Cement-supported 63/85

Type of sedimentary rocks Breccia 64/85

Conglomerates 65/85

Conglomerates 66/85

Gravelstone 67/85

Very Coarse Sandstone 68/85

Sandstone 69/85

Grain chart 70/85

Siltstone 71/85

Clay 72/85

Argillite 73/85

●Grain sorting 74/85

● Sediment fabric Точечные контакты Прямолинейные контакты Выпукло-вогнутые и сутуровидные контакты 75/85

Packing Кубическая упаковка Ромбоэдрическая Упаковка размерами двух зерен 76/85

● Roundness Standards for visual determination of the degree of roundness of Powers (1953 ) (Пауэрсу (1953)) 77/85

Physical components of the structure of sandstone and carbonate rocks 78/85

Metamorphic rocks are formed by recrystallization of older rocks ( igneous, sedimentary or metamorphic) either by direct heating (thermal metamorphism) or by heating accompanied by pressure and deformation (regional metamorphism. Metamorphic rocks 79/85

temperature pressure hydrothermal solution Basic agents recrystallized change of mineral composition change of structure and texture 80/85

regional metamorphism contact metamorphism The temperature and pressure increase; The unilateral stress occurs; Recrystallization of rocks The change takes place at the contact of intrusive bodies, operating temperature ( thermal metamorphism ) or metasomatism (action fluid ) 81/85

crystalline schist 82/85

object of study? 83/85

Core samples 84/85

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Thin Sections Well-rounded , weakly cemented sandstone Poorly sorted sandstone with pores filled with cement clay Scale: 87/85

Estimating Porosity and Permeability 88/85

Outcrop samples 89/85

Outcrop samples 90/85

Outcrop samples 91/85