CEE 1030 1st EditionExam # 1 Study GuideMid-term Study Guide- Earth Science Lecture 1Terms: - Geology- scientific study of planet earth - Physical geology- examines the materials composing earth and seeks to understand the many processes that operate beneath and on its surface. Earth’s resources. - Historical geology- seeks an understanding of the origin of earth and its development through time including future predictions - Relative dating- place rocks in the proper order without knowing their age in years - Absolute dating- use radioactive decay of certain elements to date some rock types - Igneous rocks- cooling and solidification of magma - Sedimentary rocks- derived from weathering of preexisting rocks are accumulate in layers at earth’s surface- The rock cycle- paths and processes by which rock types change at the earth’ssurface and interior - Solid earth- rock- Atmosphere- air- Hydrosphere- water- Biosphere- life Three types of plate boundaries: transform fault, divergent, convergent  Three basic rock types: igneous rocks, sedimentary rocks, metamorphic rocks The earth as a system: solid earth, atmosphere, hydrosphere, biosphere Lecture 2Terms: - Mineral- ordered internal structure (crystalline), characteristic chemical composition, inorganic, naturally occurring, distinct physical properties - Rocks- any solid mass of mineral or mineral- like matter that occurs naturally- Elements- basic building blocks of minerals, most minerals are a combinationof two or more elements - Atoms- smallest unit of an element- Nucleus- contains most of the mass of the atom- Protons- positive charge- Neutrons- no charge, neutral - Electrons- negative charge- Atomic number- number of protons - Mass number- number of protons and neutrons- Electronic structure of atoms- determines how atoms of elements bond together and with other elements - Ionic solid- electrostatic attraction between positive cations and negative anions - Iconic bonding- atoms gain or lose outermost (valence) electrons to form ions, how minerals have sodium and chloride - Covalent bonds- atoms sharing electrons - Polymorphs- minerals with the same composition but different crystalline structures  all the same mineral, different structure  physical properties- color, crystal form, luster, hardness, streak color, cleavageor fracture secondary physical properties- reaction to hydrochloric acid, double refraction, magnetism, taste, fluorescence, smell, elasticity  the silicates- most important mineral group, most rock- forming minerals Lecture 3 Terms: - igneous rocks- form by cooling and solidification of magma - magma- formed by rocks melting at the earth’s surface- extrusive or volcanic rocks- rocks formed from lava at the earth’s surface - intrusive or plutonic rocks- formed from magma at depth - texture- used to describe the overall appearance of a rock based on the size, shape, and arrangement of interlocking minerals  magma consists of three components: liquid, solids, gases igneous rocks classified/ name based on: texture, types of minerals, chemical composition  igneous textures: aphanitic, phaneritic, porphyritic, pegmatitic, pyroclastic, glassy, pumice,  three ways that melt is generated in different places: increase temperature (thermal), decrease pressure (decompression), add water (fluid induced)  magma types in order of decreasing viscosity: rhyolite, andesite, basaltic Lecture 4Terms: - non- explosive eruptions- lava flows mainly basaltic and intermediate compositions- explosive eruptions- pyroclastic deposits mainly intermediate to rhyolitic compositions - basaltic lava flows- very fluid behavior can flow at rate typically 10-200 meters/ hour, travel distances of several 100km - rhyolitic lava flows- very sticky - pahoehoe- ropy texture - Aa- rough, jagged blocky texture, very rocky - Shield volcanoes- large, broad, circular shape with gentle dipping slopes (3 to5 degrees) built by successive fluid lava flows from a central vent - Cinder cones- also known as scoria cones, built from ejected gas-rich lava fragments, have steep angles - Intermediate- rhyolitic volcanoes: composite cones or stratovolcanoes, interbedded lava flows and pyroclastic debris, potentially most dangerous volcano type, complex histories - Pyroclastic material- rapid expansion of gas bubbles results in the obliteration and fragmentation of magma and rock - Lahars- volcanic mud flows  Nature of volcanic eruptions: these factors control viscosity of a magma, this measures a material’s resistance to flow, temperature hotter magmas are less viscous (more runny) Lecture 5 Terms: - Weathering- breakdown of rocks at the earth’s surface - Erosion- physical removal of material by mobile agents - Mechanical weathering- (disintegration) breaking rocks into smaller pieces without changing their chemical composition - Chemical weathering0 (decomposition) chemical reactions between rock minerals and air + water - Frost wedging- exerts immense pressure, occurs as the result of 9% expansion of water when it is converted to ice - Root wedging- rocks on tree roots, tree will still grow but begin lean/ slowly fall- Salt wedging- evaporation of water rich in dissolved species will lead to growth of crystals in cracks- exerts force - Thermal expansion- large daily temperature changes cause thermal strain- Unloading- uplift and erosion reduces pressure - Dissolution- promoted by acidic water- Hydrolysis- reaction of mineral with water. Hydrogen ion attacks and replaces other ions - Oxidation- exposure to atmospheric oxygen - Placer deposits- resistant economic minerals- Surface area- same volume of rock, but smaller particles have greater total surface area - Rock type- rocks containing calcite (marble and limestone) readily dissolve inweakly acid solutions- Spheroidal weathering- gradual rounding of edges and corners of angular fragments - Regolith- layer of weathering products at the earth’s surface: rock and mineral fragments - Soil- combination of mineral and organic matter plus water and air. The portion of regolith that can support the growth of plants - Humus- decayed remains of animal and plant life (organic matter) essential part of soil  Two types of weathering process: mechanical and chemical  Mechanical weathering: frost wedging, root wedging, salt wedging, thermal expansion, unloading  Chemical weathering: dissolution, hydrolysis, oxidation  Physical effects of chemical