Earth Science Lecture - Test 3 Review

Earth Science Lecture m,- Test 3 Review (Thursday, December 3rd @ 4:20 p.m.) Minerals Mineral: a naturally occurring inorganic element or compound having an. orderly internal structure and characteristic chemical composition, crystal form, and physical. properties." Minerals differ from rocks, which are naturally occurring solids composed of one or more minerals. naturally occurring - naturally occurring - solid - inorganic - crystalline - chemical compound Rock: A substance made up of one or more different minerals Atom: Smallest unit into which matter can be divided without the release of electrically charged particles. Ion: an electrically charged atom Nucleus: the central part of an atom, containing its protons and neutrons atomic number: the number of protons in an atom atomic weight: the number of protons and neutrons in an atom electron shell: the position where electrons orbit an atom around its nucleus Cation: a positively charged ion Anion: a negatively charged ion ionic bonding: electron exchange covalent bonding: a chemical bonding where atoms share electrons Proton: positively charged subatomic particle Neutron: neutral zero charge subatomic particle Electron: negatively charged subatomic particle Element: a substance made up of the same type of atoms Van der Waals forces: Weak residual electric forces and the weakest type of chemical bonds physical property: any features that can be used to identify a mineral (hardness,luster,cleavage,fracture,..etc) Crystal: A near perfect geometric shape created by the orderly arrangement of atoms in a mineral crystal shape: The angle with which atoms in a mineral crystal bonds mineral cleavage: the ability of a mineral to break along smooth planes of weak atomic bonds Fracture: the absence of cleavage Hardness: Scratch test, scale of rock or mineral hardness Luster: the way a mineral reflects light either metallic (a lot of metal) or nonmetallic ( Very little metal) Streak: the color of a mineral’s powder metallic luster: a mineral containing a lot of metal so looking either bright and shiny like metal or dull thike a metal rust or tarnish nonmetallic luster: a mineral containing little metal so looks dull or glassy Mohs Hardness Scale: the list of ten minerals arranged from softest to hardest in the order that they can scratch each other specific gravity: the weight of a mineral compared to the weight of an equal volume of water -the definition of a mineral (5 parts) ●​ Naturally occurring ●​ Solid ●​ Inorganic ●​ Crystalline ●​ Chemical compound -how the different types of chemical bonds form ●​ Covalent bonds by electron sharing ●​ Ionic bonds by electron exchange ●​ Van der Waals Forces are weak, residual electronic charges - the Mohs Hardness Scale ●​ Poj ithe list of ten minerals arranged from softest to hardest in the order that they can scratch each other - how crystal shape is controlled by chemical bonds ●​ Different shapes form by the angle at which ions/atoms bond together -how cleavage and fracture are controlled by chemical bonds ●​ Weak bonds ( ionic and Van der Waals) produce cleavage, ●​ strong bonds (Covalent) produce fracture -how hardness is controlled by chemical bonds ●​ Van der Waals forces make very soft minerals, Ionic bonds are stronger and make harder minerals covalent bonds make the strongest minerals ​ -how luster, streak and specific gravity are controlled by chemical composition ●​ Minerals with a lot of metal in them have a metallic luster, dark colored streak and high specific gravity; ●​ mineral with little metal in them have a nonmetallic luster, white streak and low specific gravity Igneous Rocks and the Rock Cycle Magma: molten rock below the earth's surface Lava: molten rock at the earth's surface Crystallization: formation of minerals from liquid magma or lava use make igneous rocks Mineralogy: the amount and type of minerals found in a rock silicate minerals: minerals that contain silicon and oxygen +/- metals nonsilicate minerals: minerals that may contain silicon or oxygen +/- metals Silicon-oxygen tetrahedron: the basic chemical unit for all silicate minerals, consisting of one silicon and 4 oxygen atoms ferromagnesian silicates: silicate minerals that contain iron, calcium, and/or magnesium non ferromagnesian silicates: silicate minerals that contain sodium, aluminum, and/or potassium Texture: any feature in a rock that can give a clue to its origin Bowen's Reaction Series: the minerals that crystallize from molten rock and the order in which they crystallize from high to low temperatures fractional crystallization: a form of magmatic differentiation where minerals crystallize from a cooling magma body as it ascends and the minerals settle to the bottom of the magma chamber to form different types of igneous rocks phaneritic texture: the coarse mineral texture formed by the slow cooling of magma porphyritic texture: the fine mineral texture formed by the fast cooling of lava Rhyolite: volcanic rock made up of light colored silicate minerals Granite: a light-colored, phaneritic igneous rock diorite: a medium-colored, phaneritic igneous rock Andesite: a medium-colored, porphyritic volcanic rock Gabbro: a dark-colored, phaneritic igneous rock Basalt: a dark-colored, porphyritic volcanic rock Assimilation: when magma melts surrounding country rock and becomes contaminated magma mixing: creating different igneous rocks by mixing together raising magma bodies magmatic differentiation: any technique that can create different igneous rocks from a single magma body Phenocrysts: the large, slow-cooled minerals found in a volcanic igneous rock Groundmass: the small, fast-coolest minerals found in a volcanic igneous rock Lahar: a volcanic mudflow Laze: volcanic acid haze Vog: Volcanic smog volcanic ash: fine bits of glass where lava is blown into the air during a volcanic eruption Volatiles: the gases that escape from a hot magma body ( mostly water vapor but many other gases as well)​ fiery cloud: superheated ash flowing out of a volcano along the ground Pyroclastics: hot volcanic mud flow shield cone: a volcano made of very hot basalt lava flows composite cone: a volcano made of alternating layers of lava flows and ash eruptions lava dome: hot magma near the surface that swells up the ground into a dangerous dome cinder cone: a volcanic cone made up loose pyroclastic\ material -know the three major rock groups and their definitions: ●​ Igneous rock forms from the crystallization of magma or lava ●​ Sedimentary rock forms from the lithification of sediment ●​ Metamorphic rock forms from the metamorphism of a previously existing rock -the processes that form each of the three main rock groups ●​ Crystallization: when minerals form from liquid magma or lava to make igneous rock ●​ Lithification: when sediment is compacted or cemented to form sedimentary rock ●​ Metamorphism: when a protolith is altered by heat, pressure, or volatiles to make a metamorphic - how N.L. Bowen devised his Reaction Series to explain the mineralogy of igneous rocks ●​ He melted different igneous rocks and allowed the melt to cool very slowly while observing which minerals formed and the order that they formed in. -know Bowen’s Reaction Series ●​ the minerals that crystallize from molten rock and the order in which they crystallize from high to low temperatures -texture of plutonic and volcanic igneous rocks as it relates to cooling history ●​ Phaneritic texture is a coarse-grained texture formed by slow -cooling of magma ●​ Porphyritic texture is a fine-grained texture formed by the fast cooling of lava -the 3 types of volcanoes and where they occur ●​ Shield volcanoes form in the oceans ●​ Composite volcanoes form on the edges of continents ●​ Cinder cones form in continental interiors - the hazards associated with volcanoes ●​ Extreme heat and fire from lava, Lahars, fiery clouds, laze, pyroclastics destroying mechanical devices, plugging sewers and destroying lung tissues because it is fine glass. Sedimentary Rocks Sediment: weathered pieces or rock or hard parts of life taltal sediment: weathered pieces or rock non-detrital sediment: sediment made from the hard parts of dead plants or animal remains Weathering: all of the physical or chemical processes that can break down rock into sediment physical weathering: any form of weather that applies a physical force to rocks to break them down chemical weathering: the break down of rock into sediment by combining it with natural surface chemicals frost wedging: physical weathering where water in cracks in rock freezes, expands and breaks up the rock Exfoliation: the expansion and break up of rock by removing rock that was on top of it (called overburden ​ Abrasion: physical weathering where water or wind bangs sediment together to break it down plant root pressure: physical weathering where plant roots grow into cracks in rock seeking water and expand to break up the rock Oxidation: chemical weathering involving a chemical reaction of minerals with oxygen to form rust Acidation: natural carbonic acid in surface water that breaks down and dissolves minerals in a rock Hydration: the chemical combination of water to minerals to break them down into clay Lithification: any process that can convert loose sediment into sedimentary rock Dehydration: the drying up of fine sediments such as clay to lithify it into a rock Compaction: a form of lithification of fine-grained sediment, such as clay Cementation: a form of lithification of coarse-grained sediment by filling the sediments pores (openings) with other minerals Quartz: the most chemically stable silicate mineral at the earth's surface Clay: the weathering product of most silicate minerals Calcite: fossil limestone Carbon: the major material that makes up the sedimentary rock coal, formed by the compaction of dead plant material (compacted dead plant) Sandstone: a sedimentary rock made by the cementing of quartz sand Shale: Rock made of compacted clay Limestone: a sedimentary rock made by the cementing of calcite sea shells coal: a sedimentary rock made by the compaction of carbon from dead plants - how Bowen’s Reaction series relates to a mineral’s chemical stability ●​ The higher the temperature the more unstable a mineral is and the more likely it will decompose to clay - how the different types of physical weathering break down rocks ●​ Most forms of physical weathering use water in some form to apply a force to the rocks in order to break them down. - how the different types of chemical weathering break down rocks ●​ Most forms of physical weathering use water in some form to apply a force to the rocks in order to break them down - the types of detrital and non-detrital sedimentary rocks ●​ detrital - sandstone and shale ●​ non-detrital - coal and limestone - the processes that can lithify a sedimentary rock ●​ for fine grained sediment - compaction and dehydration ●​ for coarse grained sediment - cementation - the compositions of detrital and non-detrital sedimentary rocks ●​ Detrital, sandstone - quartz, shale - clay. ●​ Non-detrital, limestone - calcite, coal - carbon Metamorphic Rocks metamorphic rock: any previously existing rock (protolith) that has been altered by heat, pressure and/or volatiles geothermal gradient: the deeper you go into the earth, the hotter it gets lithostatic pressure: the pressure of the weight of overlying rock as you go deeper into the earth Metamorphism: the process of converting any protolith into a metamorphic rock by heat, pressure and/or volatiles regional metamorphism: A lot of pressure gives the rock a texture contact metamorphism: metamorphism formed by heat and volatiles, forms rocks with a nonfoliated texture Schist: a regional metamorphic rock formed from a shale protolith Gneiss: a regional metamorphic rock formed from a granite protolith Quartzite: a contact metamorphic rock formed from a sandstone protolith Marble: a contact metamorphic rock formed from a limestone protolith Protolith: Whatever a metamorphic rock was before it was metamorphosed. Recrystallization: a metamorphic process that occurs under temperature and pressure where atoms of a mineral are reorganized by diffusion and/or dislocation glide. Mineral rotation: what pressure does to minerals as you go deeper into the earth foliated texture: Where the minerals have been crushed and lined up due to pressure of regional metamorphism. nonfoliated texture: contact metamorphism index minerals: minerals whose presence in a rock give you an idea of the temperatures and pressures they form under during regional metamorphism - the processes that metamorphose a rock: ●​ heat, pressure and/or volatiles - where does regional and contact metamorphism occur? ●​ regional - anywhere below about 3 miles in the earth and in old mountain ranges ●​ ●​ contact - adjacent to hot magma bodies - the protoliths for the different types of metamorphic rocks ●​ Limestone protolith makes Marble ●​ Sandstone protolith makes Quartzite ●​ Shale protolith makes Slate. -how contact metamorphism alters the protolith ●​ Recrystallization. Makes minerals grow larger and rock harder and stronger. (no pressure involved) -how regional metamorphism alters the protolith ●​ Both recrystallization and rotation and alignment of minerals. (pressure) ●​ It causes minerals to grow in size( recrystallization) and also causes them to rotate and align to form a foliated texture History of the Earth Differentiation: the melting and separation of the Earth into a core, mantle and crust Eon: the largest subdivision of geologic time Theia: the Mars-sized impactor the hit the Earth and created our moon Hadean Eon: When earth finished accretion. Surface is mostly magma. Earth was spinning faster. ​ Archean Eon: the second major subdivision of geologic time from 4.0 Ga (billion years) to 2.5 Ga ago Proterozoic Eon: the third major subdivision of geologic time from 2.5 Ga (billion years) to roughly 0.54 Ga ago Phanerozoic Eon: the fourth and final major subdivision of geologic time from roughly 0.54 Ga ago to the present Era: a subdivision of the larger Eons of time Paleozoic Era: the Era of 'old life', the first subdivision of the Phanerozoic Eon Mesozoic Era: The Mesozoic Era is known as the Age of the Reptiles Cenozoic Era: The Cenozoic Era (the youngest one) is known as the Age of the Mammals Fossils: any direct or indirect evidence of past life Stromatolites: one of the earliests fossils, a form of blue-green photosynthetic algae Metazoans: organisms whose individual cells have specialized to form organs such as heart,eyes, stomach,skin,lungs,.... etc. Invertebrates: animals with no backbone Vertebrates: animals with a backbone Amphibians: Animals that spend part of their life cycle in water and part on land (ex. Frog) Reptiles: Hard egg with shell (amniotic egg) No life cycle in water. They live on land. amniotic egg: A hard egg with a shell Dinosaurs: Large predatory reptile. Are extinct. Mesozoic age. Mammals: Don’t lay eggs. Cenozoic age. Most recent age. Rodinia: the first supercontinent formed in the Proterozoic Eon Pangea: the last great supercontinent formed in the Paleozoic Era Age of the Invertebrates: dominate predators in Early Paleozoic Era Age of Fish: dominate predators in Middle Paleozoic Era Age of Amphibians: dominate predators in Late Paleozoic Era Age of the Reptiles:dominate predators in the Mesozoic Era Chicxulube: the meteorite crater in the Yucatan Peninsula believed to cause the extinction of the dinosaurs Age of the Mammals: dominate predators in the Mesozoic Era Holocene Epoch: recent time, the time period we live in - the current theory for how our Moon formed ​ Theia - the Mars-sized impactor the hit the Earth during the Archean Eon and blew out the material that created our moon -the current theory for how our Moon formed - during the early Hadean Eon when the Earth was still accreting a Mars-sized body named Theia collided with the Earth and blew out material that later accreted and became our Moon - know the major geologic events that occurred within the 4 Eons 1.​ within Hadean Eon - Earth finished accretion and the formation of the Moon 2.​ within Archean Eon - the formation of continental shields 3.​ within the Proterozoic Eon - evolution of complex soft-bodied life 4.​ within Phanerozoic Eon - evolution of complex hard-bodied life - the geologic events that mark the boundaries between the 4 Eons 1.​ beginning of the Phanerozoic - first hard-shelled animals 2.​ beginning of Proterozoic - once thought to be earliest fossils, not true now 3.​ beginning of the Archean - formation of atmosphere, oceans and first rock 4.​ beginning of Hadean - accretion of the Earth - how the Eras of the Phanerozoic eon are named. ●​ Cenozoic - young life (mostly still living today) ●​ Mesozoic - middle life (some animals extinct, some not) ●​ Paleozoic - old life (most animals extinct)