geology chapter 1 part 2.pdf

GENERAL GEOLOGY CHAPTER 1 FLORENCE T. SAMONTE  Branches of Geology FLORENCE T. SAMONTE  Branches of Geology (Disciplines) CHRONOLOGY TECTONICS NATURA...

GENERAL GEOLOGY CHAPTER 1 FLORENCE T. SAMONTE  Branches of Geology FLORENCE T. SAMONTE  Branches of Geology (Disciplines) CHRONOLOGY TECTONICS NATURAL RESOURCES SEDIMENTS/ROCKS Stratigraphy Tectonics Petrology Sedimentology Paleontology Volcanology Mineralogy Surficial Geology Micropaleontology Seismology Gemology Glaciology Paleomagnetism Neotectonics Crystallography Geophysics Geomorphology Tectonophysics Soil Science Bedrock Geology Paleoseismology Seismotectonics Pedology Lithology Magnetostratigraphy Edaphology TOPOGRAPHY ASTROGEOLOGY Geochronology Agronomy/Agrology Orography Astrogeology Hydrogeology FLORENCE T. SAMONTE Topography Areology Pomology Hypsometry Selenography Exogeology READ!!! https://earthhow.com/branches-of-geology/  Earth Structure and Composition FLORENCE T. SAMONTE  LAYERS OF THE ATMOSPHERE https://www.sciencefacts.net/layers-of-atmosphere.html LAYERS OF THE EARTH FLORENCE T. SAMONTE https://www.sciencefacts.net/wp-content/uploads/2020/06/Layers-of-The-Earth.jpg  LAYERS OF THE ATMOSPHERE https://www.sciencefacts.net/layers-of-atmosphere.html THE ATMOSPHERE The atmosphere of the earth is the layer of gases (commonly called air) that surrounds the earth and creates an inhabitable environment, maintains temperature, causes weather, and protects its inhabitants from solar radiation. LAYERS OF THE ATMOSPHERE ▪ Troposphere ▪ Stratosphere FLORENCE T. SAMONTE ▪ Mesophere ▪ Thermosphere ▪ Exosphere  LAYERS OF THE ATMOSPHERE https://www.sciencefacts.net/layers-of-atmosphere.html TROPOSPHERE EXTENT 5 – 10 mi (8 – 15 km) above the surface TEMPERATURE 62°F (17°C) around the lowest point to -60°F (-51°C) near the top COMPOSITION Atmospheric water vapor Dust FLORENCE T. SAMONTE All the weather we experience Earth’s jet streams  LAYERS OF THE ATMOSPHERE https://www.sciencefacts.net/layers-of-atmosphere.html STRATOSPHERE EXTENT 31 mi (50 km) above the surface TEMPERATURE -60°F (-51°C) near the tropopause to 5°F (-15°C) near the next layer COMPOSITION Ozone layer FLORENCE T. SAMONTE  LAYERS OF THE ATMOSPHERE https://www.sciencefacts.net/layers-of-atmosphere.html MESOPHERE EXTENT 85 mi (140 km) above the surface TEMPERATURE 5°F (-15°C) to -148°F (-100°C) as one ascends up the layer CONTENTS meteoroids burn up here FLORENCE T. SAMONTE  LAYERS OF THE ATMOSPHERE https://www.sciencefacts.net/layers-of-atmosphere.html THERMOSPHERE EXTENT 372 mi (600 km) above the surface TEMPERATURE 930°F (500°C) to 3,600°F (2,000°C) near the upper thermosphere CONTENTS Aurora Borealis (North Pole) and Aurora Australis (South Pole) FLORENCE T. SAMONTE  LAYERS OF THE ATMOSPHERE https://www.sciencefacts.net/layers-of-atmosphere.html EXOSPHERE EXTENT 620 mi (1000 km) above the surface TEMPERATURE 1800°F (980°C) COMPOSITION Helium Hydrogen FLORENCE T. SAMONTE  LITHOSPHERE CONDITION LAYERS OF THE EARTH Coolest and most rigid part of the Earth COMPOSITION/LAYERS All solid materials composing the Earth The most well-known feature associated with the Earth’s lithosphere is tectonic activity which describes the interaction of the huge slabs of lithosphere FLORENCE T. SAMONTE called tectonic plates. https://education.nationalgeographic.org/resource/lithosphere/ https://www.sciencefacts.net/wp-content/uploads/2020/06/Layers-of-The-Earth.jpg  CRUST CONDITION LAYERS OF THE EARTH Temperature varies with depth COMPOSITION/LAYERS Oceanic crust and continental crust Oceanic plates lie under oceans. They're denser compared to continental crust, meaning they have more mass per unit volume. Continental crust is located under land masses and is less FLORENCE T. SAMONTE dense than oceanic plates. https://study.com/academy/lesson/how-density-buoyancy-affect-plate- tectonics.html#:~:text=Oceanic%20plates%20lie%20under%20oceans,less%20dense%20than%20oceanic%20plat es. https://www.sciencefacts.net/wp-content/uploads/2020/06/Layers-of-The-Earth.jpg https://www.sciencefacts.net/wp-content/uploads/2020/06/Layers-of-The-Earth.jpg FLORENCE T. SAMONTE https://earthhow.com/7-major-tectonic-plates/  PACIFIC PLATE EURASIAN PLATE FLORENCE T. SAMONTE  NORTH AMERICAN PLATE SOUTH AMERICAN PLATE FLORENCE T. SAMONTE  AFRICAN PLATE ANTARCTIC PLATE INDO-AUSTRALIA PLATE FLORENCE T. SAMONTE  MANTLE CONDITION LAYERS OF THE EARTH Temperature varies from 1000°C (1832°F) near its boundary with the crust, to 3700°C (6692°F) near its boundary with the core LAYERS Upper mantle Asthenosphere Lower mantle Geological processes such as FLORENCE T. SAMONTE volcanism, seismic activity and formation of mountains (orogeny*) originate in the mantle. https://www.sciencefacts.net/wp-content/uploads/2020/06/Layers-of-The-Earth.jpg https://www.sciencefacts.net/wp-content/uploads/2020/06/Layers-of-The-Earth.jpg  https://www.youtube.com/watch?v=69Hkolfugw4 https://www.youtube.com/watch?v=HSeO_tHNn-I https://www.youtube.com/watch?v=PDrMH7RwupQ FLORENCE T. SAMONTE  CORE CONDITION LAYERS OF THE EARTH Temperature in the outer core is between 4,000° and 5,700°C Temperature in the inner core is about 5,500°C LAYERS Outer core Inner core FLORENCE T. SAMONTE https://www.sciencefacts.net/wp-content/uploads/2020/06/Layers-of-The-Earth.jpg https://www.sciencefacts.net/wp-content/uploads/2020/06/Layers-of-The-Earth.jpg  CORE CONDITION The churning metal of the outer Temperature in the outer core is core creates and sustains Earth’s between 4,000° and 5,700°C magnetic field. Temperature in the inner core is about The inner core grows as bits of the 5,500°C liquid outer core solidify or LAYERS crystallize. Outer core Geoscientists cannot study the core directly. Inner core All information about the core has come from sophisticated reading of seismic data, FLORENCE T. SAMONTE analysis of meteorites, lab experiments with temperature and pressure, and computer modeling.  Continental Drift and Plate Tectonics FLORENCE T. SAMONTE FLORENCE T. SAMONTE https://www.youtube.com/watch?v=OGdPqpzYD4o&ab_channel=ArcGIS  Theory 1: Continental Drift In 1912, a German meteorologist, Alfred Wegener, suggested that 200-300 million years ago, in the Paleozoic and Mesozoic eras, there was a single supercontinent, which he called Pangea (which means “all Earth”). FLORENCE T. SAMONTE https://www.scienceforthepublic.org/they-didnt-believe-it/continental-drift FLORENCE T. SAMONTE https://letstalkgeography.com/continental-drift-theory/#google_vignette 225 MYA Permian Period 65 MYA Cretaceous Period ▪ The continents fit together 200 MYA Triassic Period Evidences of Continental Drift Theory 150 MYA Jurassic Period Present Days https://geo.libretexts.org/Bookshelves/Geology/Fundamentals_of_Geology_(Schulte)/05%3A_Plate_Tectonics/5.05%3A_Continental_Drift  Evidences of Continental Drift Theory ▪ Identical rocks, of the same type and age, are found on both https://geo.libretexts.org/Bookshelves/Geology/Fundamentals_of_Geology_(Schulte)/05%3A_Plate_Tectonics/5.05%3A_Continental_Drift sides of the Atlantic Ocean. FLORENCE T. SAMONTE https://www.kvaroyarctic.com/interesting-facts-about-the-atlantic-ocean  Evidences of Continental Drift Theory ▪ Mountain ranges with the same rock types, structures, and ages are now on opposite sides of the Atlantic Ocean. FLORENCE T. SAMONTE https://www.reddit.com/r/interestingasfuck/comments/10ku6cu/the_scottish_highlands_the_app https://www.kvaroyarctic.com/interesting-facts-about-the-atlantic-ocean alachians_and_the/#lightbox FLORENCE T. SAMONTE https://education.nationalgeographic.org/resource/continental-drift/ Evidences of Continental Drift Theory continents that are now widely separated animals are found in rocks of the same age but are on ▪ Ancient fossils of the same species of extinct plants and https://geo.libretexts.org/Bookshelves/Geology/Fundamentals_of_Geology_(Schulte)/05%3A_Plate_Tectonics/5.05%3A_Continental_Drift  Evidences of Continental Drift Theory ▪ Grooves and rock deposits left by ancient glaciers are found today on different continents very close to the equator. Grooves in limestone, carved 35,000 years ago by the Wisconsin glacier, in Ohio. https://www.sciencephoto.com/media/444089/view/glacial-grooves-in-limestone FLORENCE T. SAMONTE  Evidences of Continental Drift Theory ▪ Coral reefs and coal-forming swamps are found in tropical and subtropical environments, but ancient coal seams and coral reefs are found in locations where it is much too cold today. FLORENCE T. SAMONTE Coal formation begins in swampy areas in warm tropical climates. The tropical swamp forests developed in the Carboniferous period of Earth’s history. The Carboniferous Period lasted from about 359.2 to 299 million years ago* during the late Paleozoic Era. https://ucmp.berkeley.edu/carboniferous/carboniferous.php  Theory 2: Plate Tectonics In the 1960s, scientific advances confirmed the theory of “plate tectonics,” –the source of the energy and mechanics of plate movement on the Earth’s crust. ▪ Continental drift over millions of years was caused by plate tectonics. ▪ Plate tectonics also explained how the movement of the plates create volcanoes and earthquakes, and how the collision between continents gave rise to huge mountain ranges. ▪ At present, geologists can calculate when and where plate FLORENCE T. SAMONTE movements occurred over millions of years. Some famous contributors: Harry Hess, Fred Vine and Drummond Matthews  Theory 2: Plate Tectonics The continents rest on massive slabs of rock called tectonic plates which are always moving and interacting in a process called plate tectonics. The continents are still moving today. Some of the most dynamic sites of tectonic activity are seafloor spreading zones and giant rift valleys. FLORENCE T. SAMONTE FLORENCE T. SAMONTE https://earthhow.com/7-major-tectonic-plates/  A divergent boundary occurs when two tectonic plates move away from each other. Along these boundaries, earthquakes are common and magma (molten rock) rises from the Earth’s mantle to the surface, solidifying to create new oceanic crust. FLORENCE T. SAMONTE https://oceanexplorer.noaa.gov/facts/plate-boundaries.html  When two plates come together, it is known as a convergent boundary. The impact of the colliding plates can cause the edges of one or both plates to buckle up into mountain ranges or one of the plates may bend down into a deep seafloor trench. FLORENCE T. SAMONTE https://oceanexplorer.noaa.gov/facts/plate-boundaries.html  At convergent plate boundaries where an oceanic plate meets a continental plate, oceanic crust is forced down into the Earth’s mantle and begins to melt. The melted rock rises into and through the overlying plate as magma, often forming a chain of volcanoes parallel to the plate boundary. FLORENCE T. SAMONTE https://oceanexplorer.noaa.gov/facts/plate-boundaries.html  Convergence of oceanic plates is when two oceanic plates collide. The more dense of the two will be forced underneath the other into the Earth's mantle; this is called subduction. FLORENCE T. SAMONTE https://oceanexplorer.noaa.gov/facts/plate-boundaries.html  Two plates sliding past each other forms a transform plate boundary. FLORENCE T. SAMONTE https://www.youtube.com/watch?v=tIuk2blBzHs FLORENCE T. SAMONTE https://www.age-of-the-sage.org/tectonic_plates/boundaries_boundary_types.htm FLORENCE T. SAMONTE Magma  https://opentextbc.ca/geology/chapter/3-2-magma-and-magma-formation/ FLORENCE T. SAMONTE Mantle convection refers to the process of rising hot mantle material and sinking colder material. In geology, a hotspot is an area of the Earth’s mantle from which hot plumes rise upward, forming volcanoes on the overlying crust.  Magma Magma is a molten and semi-molten rock mixture found under the surface of Earth. This mixture is usually made up of four parts: a) a hot liquid base, called the melt; b) minerals crystallized by the melt; c) solid rocks incorporated into the melt from the surrounding confines; and d) dissolved gases water (vapor, carbon dioxide, and sulfur gases, with lesser amounts of hydrogen, hydrochloric acid, and hydrofluoric acid) Magma is extremely hot—between 700° and 1,300° Celsius (1,292° and 2,372° Fahrenheit). This heat makes magma a very fluid and dynamic substance, able FLORENCE T. SAMONTE to create new landforms and engage physical and chemical transformations in a variety of different environments. https://education.nationalgeographic.org/resource/magma-role-rock-cycle/ FLORENCE T. SAMONTE Ways Magma Form  How Magma Forms Differences in temperature, pressure, and structural formations in the mantle and crust cause magma to form in different ways. a) Decompression Melting b) Transfer of Heat c) Flux Melting FLORENCE T. SAMONTE https://education.nationalgeographic.org/resource/magma-role-rock-cycle/  Decompression melting - the upward movement of Earth's mostly solid mantle. - the reduction in overlying pressure that enables the mantle to melt and form magma. FLORENCE T. SAMONTE http://www.fccj.us/vocabulary/Tarbuck/Chapter9/09_26.html FLORENCE T. SAMONTE https://steemit.com/geology/@keephy/a-brief-explanation-why-the-pacific-northwest-of-america-has-volcanoes  Magma Escape Routes Magma leaves the confines of the upper mantle and crust in two major ways: ▪ as an intrusion (pluton) – Ex.: dikes and xenoliths ▪ as an extrusion – Ex.: lava and volcanic rock FLORENCE T. SAMONTE https://education.nationalgeographic.org/resource/magma-role-rock-cycle/  Magmatic Dikes Magmatic Dikes Baranof Cross-Island Trail, Alaska Makhtest Ramon, Isreal https://www.reddit.com/r/geology/comments/mp1fgk/a_magmatic_dyke_in_makhtest_ramon_isreal/ FLORENCE T. SAMONTE https://education.nationalgeographic.org/resource/dike/ A magmatic dike is simply a large slab of magmatic material that has intruded into another rock body.  Xenolith Rock Ontario, Canada A xenolith is a piece of rock trapped in another type of rock. https://arkansasgeological.wordpress.com/2015/10/15/geopic-of-the-week-xenolith/ Xenolith Rock Little Rock Arkansas http://4.bp.blogspot.com/- RxeQHjX_rGg/Tcv1Beec_DI/AAAAAAAAA8U/ScydTWfKDHE/s1600/Schott_Xenolith_1.jpg FLORENCE T. SAMONTE Xenolith Rock Sierra Nevada California https://en.wikipedia.org/wiki/Xenolith#/media/File:XenolithSierra.JPG  Lava Flow Reykjanes Peninsula, Iceland Lava eruptions can be “fire fountains” of liquid rock or thick, slow-moving rivers of molten material. FLORENCE T. SAMONTE https://www.wanderlust.co.uk/content/spectacular-volcanoes-that-are-active-right-now/  Tephra (Volcanic Ash) Kyodo Japan Magma can also extrude into Earth’s atmosphere as part of a violent volcanic explosion. FLORENCE T. SAMONTE Pumice Rock https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019JB018902 https://www.thoughtco.com/pumice-rock-4588534  Magma Chamber The location beneath the vent of a volcano where molten rock (magma) is stored prior to eruption. Also known as a magma storage zone or magma reservoir. https://volcanoes.usgs.gov/vsc/glossary/magma_chamber.html FLORENCE T. SAMONTE FLORENCE T. SAMONTE https://www.biorender.com/template/volcano-anatomy  Magma Chamber If a magma chamber encounters an enormous amount of pressure, however, it may fracture the rock around it. The cracks, called fissures or vents, are tell-tale signs of a volcano. Many volcanoes sit over magma chambers. As a volcano’s magma chamber experiences greater pressure, often due to more magma seeping into the chamber, the volcano may undergo an eruption. An eruption reduces the pressure inside the magma chamber. As long as more magma pools into a volcano’s magma chamber, there is the possibility of an eruption and the volcano will remain active. FLORENCE T. SAMONTE https://education.nationalgeographic.org/resource/magma-role-rock-cycle/  Fissures (Icelandic Volcano) Iceland FLORENCE T. SAMONTE https://www.forbes.com/sites/davidbressan/2021/04/05/new-fissure-with-lava-fountains-opens-near-icelandic-volcano/  Fissures (or Fumaroles) US FLORENCE T. SAMONTE https://www.nps.gov/articles/000/fumaroles.htm  Magma Chamber Large eruptions can nearly empty the magma chamber. The layers of magma may be documented by the type of eruption material the volcano emits. Gases, ash, and light-colored rock are emitted first, from the least-dense, top layer of the magma chamber. Dark, dense volcanic rock from the lower part of the magma chamber may be released later. In violent eruptions, the volume of magma shrinks so much that the entire magma chamber collapses and forms a caldera. Craters are formed by the outward explosion of rocks and other materials from a volcano. Calderas are formed by the inward collapse of a volcano. FLORENCE T. SAMONTE https://education.nationalgeographic.org/resource/magma-role-rock-cycle/ FLORENCE T. SAMONTE FLORENCE T. SAMONTE https://www.youtube.com/watch?v=gQRt2NCmEw8&ab_channel=MacmillanLearning  Laguna de Quiltoa Ecuador FLORENCE T. SAMONTE https://education.nationalgeographic.org/resource/calderas/  Apolaki Caldera Philippines FLORENCE T. SAMONTE The Apolaki Caldera is a volcanic caldera with a diameter of 150 kilometers (93 mi), making it the world's largest caldera. It is located within the Benham Rise(Philippine Rise) and was discovered in 2019 by Jenny Ann Barretto, a Filipino marine geophysicist and her team. https://plnmedia.com/filipina-geophysicist-discovers-worlds-largest-caldera-in-benham-rise/  Types of Magma ▪ Mafic Magma Mafic magma has relatively low silica content, roughly 50%, and higher contents in iron and magnesium. This type of magma has a low gas content and low viscosity, or resistance to flow. Mafic magma also has high mean temperatures, between 1000o and 2000o Celsius (1832° and 3632° Fahrenheit), which contributes to its lower viscosity. Low viscosity means that mafic magma is the most fluid of magma types. It erupts non-explosively and moves very quickly when it reaches Earth’s surface as lava. This lava cools into basalt, a rock that is heavy and dark in color due to its higher iron and magnesium levels. Basalt is one of the most common rocks in FLORENCE T. SAMONTE Earth’s crust as well as the volcanic islands created by hot spots. The Hawaiian Islands are a direct result of mafic magma eruptions. Steady and relatively calm “lava fountains” continue to change and expand the “Big Island” of Hawaii. https://education.nationalgeographic.org/resource/magma-role-rock-cycle/  Types of Magma ▪ Intermediate Magma Intermediate magma has higher silica content (roughly 60%) than mafic magma. This results in a higher gas content and viscosity. Its mean temperature ranges from 800° to 1000° Celsius (1472° to 1832° Fahrenheit). As a result of its higher viscosity and gas content, intermediate magma builds up pressure below the Earth’s surface before it can be released as lava. This more gaseous and sticky lava tends to explode violently and cools as andesite rock. Intermediate magma most commonly transforms into andesite due to the transfer of heat at convergent plate boundaries. Andesitic rocks are often found at continental volcanic arcs, such as the Andes FLORENCE T. SAMONTE Mountains in South America, after which they are named. https://education.nationalgeographic.org/resource/magma-role-rock-cycle/  Types of Magma ▪ Felsic Magma Felsic magma has the highest silica content of all magma types, between 65-70%. As a result, felsic magma also has the highest gas content and viscosity, and lowest mean temperatures, between 650° and 800° Celsius (1202° and 1472° Fahrenheit). Thick, viscous felsic magma can trap gas bubbles in a volcano’s magma chamber. These trapped bubbles can cause explosive and destructive eruptions. These eruptions eject lava violently into the air, which cools into dacite and rhyolite rock. Much like intermediate magma, felsic magma may be most commonly found at convergent plate boundaries where transfer of heat FLORENCE T. SAMONTE and flux melting create large stratovolcanoes. https://education.nationalgeographic.org/resource/magma-role-rock-cycle/  Silica content Mean Temperature Type of Magma Viscosity Level % C Mafic  50 1000 – 2000 Low Intermediate 50 - 60 800 - 1000 High Felsic 65 – 70 650 - 800 Higher Types of Magma FLORENCE T. SAMONTE https://opentextbc.ca/geology/chapter/3-3-crystallization-of-magma/  Rhyolithic Columnar Formation (Felsic) Sai Kung, Hong Kong, China FLORENCE T. SAMONTE https://openpress.usask.ca/physicalgeology/chapter/7-3-classification-of-igneous-rocks-2/  Andes Mountains (Intermediate) South America FLORENCE T. SAMONTE https://en.wikipedia.org/wiki/Andes#/media/File:Cordillera_de_los_Andes.jpg  Andesite (Intermediate) Colima Volcano, Mexico FLORENCE T. SAMONTE https://www.volcanodiscovery.com/ru/photo-of-the-day/2015-oct-2.html FLORENCE T. SAMONTE https://openpress.usask.ca/physicalgeology/chapter/7-3-classification-of-igneous-rocks-2/ California, US Basaltic Columns (Mafic)