Geology Test 1
List the major types of natural hazards and the associated risks.
Natural Hazards- prepare society for inevitable natural disasters such as earthquakes, hurricanes, floods, and volcanic eruptions. NOT RANDOM ACTS Hurricanes- "Storm Surge" can flood costal areas and is caused y low pressures, high winds, and rains Floods- water flows into a region faster than it can flow out. Deposit sediments containing minerals and organic nutirents on the flood plains making them fertile lands. Earthquake - Breaking of rocks along geologic faults. destructive to built enviornement, ripping apart urban infrastructure and causing buildings to collapse.Landslides and fires, tsunamis. Volcanic eruption- provide society with mineral resources, fertile soil, and thermal energy. lava is a threat to community. eruption of ash clouds can damage planes. Landslides- caused by rainfall, earthquakes, hurricanes, and other natural hazards. Bolides- explosions
List the basic non-silicate mineral groups and their basic composition
carbonate- calcite/dolomite sulfate- gypsum sulfide- pyrite/galena oxides-hematite
List three common greenhouse gasses and describe the characteristics of a greenhouse gas.
absorbs and emits radiant energy within the thermal infrared range carbon dioxide, water, ozone (all 3 atoms)
Define the Earth System and the four components of the Earth System
all parts of our planet and all their interactions taken together. if one part changes so does every other part. Geosphere- rocks hydrosphere- water biosphere-plants, life atmosphere- air
Define the three main ways that minerals form.
critical temp/ concentration- low temperature and hot temperature Crystal nucleation- from a solution, a liquid, or a vapour crystal growth- growth along the sides, corners, and ridges conteoled by surface charges ideal crystals form by growth in unrestricted space. in restricted space crystals begin to lose their ideal crystal form -Through crystallization of melted materials -Through crystallization of minerals dissolved in water -Through crystallization of minerals when solutions evaporate
Explain how sea-floor spreading leads to the formation of new crust and to predictable variations in: 1) the topography of the sea floor; 2) the age of the crust; and to the magnetic signal of the ocean crust.
crust is being created and the earth is getting bigger. 1.New seafloor is created along the rift at the crest of mid ocean ridge as the plates move apart 2. magnetized in the direction of earths magnetic field at the time. Half magnetized material moves to each side. the magnets work as a magnetic tape recorder that encodes the history of the opening of the oceans shown by magnetic chrons
Identify the different topographic and geologic features in a side view (cross-section) of a plate boundary
divergent- plates move apart and a rift is created convergent- plats come together and a trench, mountains, or volcano is created transform- mid ocean ridges
Explain the significance of the silicon-oxygen tetrahedron and contrast the differences in arrangement of the tetrahedron among the different groups of silicate minerals including how the different arrangements change the silica content of the silicate groups.
it often bonds to cations to form electrically neutral minerals; it can share oxygen ions with other silicon-oxygen tetrahedra; may be isolated or may be linked to other silicate tetrahedra in rings, single chains, double chains, sheets, or frameworks
Explain why there is more dissolved oxygen at the surface of the oceans near the poles compared. to the surface of the oceans near the equator.
more oxygen is dissolved in cold waters than in warm waters
List the primary sequence of processes that lead to the formation of a crystal.
most minerals grow in fluid. growth along corners, ridges, and faces mainly controlled by surface charges, ideal crystal forms are produced by growth in an unrestricted space. in restricted space crystals begin to lose their ideal crystal form starts with the formation of microscopic single crystals
Define the characteristics of an economic mineral and describe the four general processes of how minerals are concentrated as ore minerals (vein, disseminated, igneous and sedimentary).
must be easily extractible and economically viable vein-hypothermal solutions move through featured rock and often deposit ore minerals. resulting in tabular (sheet like) deposits of precipitated minerals in the fractures and joints are called veins. Source of metallic ores. disseminated- mineral deposits that are scattered through volumes of rock much larger than veins. igenous- segrations of ore minerals near the bottoms of intrusions, these deposits form when minerals crystalize from molten magma, settle and accumulate on the floor of a magma chamber sedimentary- most valuable mineral sources, source of copper, iron and other minerals. rifting of the continental crust led to development of a deep trough where sediments and ore minerals were deposited in a very still and narrow sea
Explain what a mineral is and how it differs from a rock.
naturally occuring, inorganic, solid, specific internal atomic structure, slightly varying chemical compositiion, crystaline rocks are made up of two or more minerals
List the three most common gasses in the atmosphere.
nitrogen, oxygen, carbon dioxide, argon, water vapor
Using the principle of isostasy, predict the vertical motion of the Earth's crust caused by changes in the thickness of the crust and/or density of the crust.
ocean crust- thinner and denser continental crust- thicker and less dense earthquakes can happen at shallow or deep, thick crust unde most mountains
Contrast the differences in wavelengths between sunlight and Earth's radiant energy.
the shorter amount of radiation, the hotter, the longer amount of radiation, the cooler
Describe the relationship between the temperature and the wavelength of radiant energy.
the shorter the wavelength the hotter the temperature, the longer the wavelength the cooler the temperature
Explain why the ocean is layered and define the thermocline.
thermocline: the line or area of the ocean where the temperature changes dramatically
List the steps of the classical scientific method and explain limitations of the classically presented scientific method.
0. Question 1. Observation 2. hyphothesis 3. prediction 4. expiriement 5. interpret/ evaluate Limitations- Hypothesis may be testifiable or falsifiable, observations must be physical and repeatable and may have patterns that allow for comparison. Theory must survive numerous falsificaiton test
Explain the grading system and how students are assessed in this course.
1) Exams —30% There are THREE scheduled exams—the lowest exam score will be dropped. 2) In-Class Exercises—15% 3) On-line Quizzes—15% 4) Digital Projects—15% 5) LAB—25%
List the expectations that the instructor has for the course and list the course objectives
1) understanding of Earth processes and their interactions in shaping Earth's features, natural resources, and history. 2) To comprehend the vastness of geologic time and how scientists infer this history. 3) To understand that natural resources and natural "disasters" are controlled by "natural" geologic processes and are unequally distributed over Earth. 4) To apply scientific thinking to cases to appraise how life has made significant changes to the Earth at all scales. 5) To collaboratively analyze Earth Science data, graphs or articles and to critically evaluate these in order to make informed economic, political and ethical decisions.
List the primary characteristics of scientific reasoning
1. Repeatable 2. Observable 3. Natural 4. Predictable 5. testable 6. tentative Science is- accumulate knowledge with branches based on expiriment, observation, you can disprove, change, and its the natural world Science is not- based on proof, belief, decided by debate or law, search for truth, fair
Give an example of the inter-relationship between each of four components of the Earth System
Carbon Cycle: biosphere- carbon dioxide is used by plants for photsynthesis Atmosphere- respiration release carbon dixoide back into the enviornment geosphere- co2 is used in rocks as carbonate hydrosphere-by the ocenas these rocks are Volcanic eruption: Atmosphere- gasses are released Geosphere- molten lava forms rocks biosphere- eruption kills plants/ organisms hydrosphere- where volcanos are formed
List and identify the main geologic layers in Earth
Crust-iron poor rock (silicitate) Mantle- iron rich rocks (siliciate) Core- pure iron and nickle, outer part is liquid
Define density and explain how density of rocks can vary.
Density- how heavey somehing is The density of rocks can vary based of where they were formed on the earth and what they are composed of (iron, nickel, etc)
Compare and contrast the main plate boundaries in terms of — topography (e.g. presence of ridges, trenches, mountains and island chains) — earthquakes (location and depth of the earthquake)
Divergent- mid ocean ridges, ridges from hotter than normal rock, colder gets more dense, continential plates seperate and it leads to a continental rift. volcanos are concentrated along rift. earthquakes occur at the ridges and they are shallow because of the new crust, form valleys and mountains convergent- continential, ocean, contient & ocean crush squeezed to become thick, continenal has no subduction, plate that goes under is shallow to deep. Volcanic chain, c vs. c has no volcanos because neither continents want to budge, crust doesnt melt. earthquakes are close to the surface but as friction happens it goes to deeper depths lots of scattered earthquakes 1. continents are old, mostly from old collisions, middle is the oldest because they cant get submerged underneath and melted 2.transform boundaries= plates slide past eachother, volcanos 3. ridge push and slab pull drives plate motion, whole mantle convection
List the six most abundant elements in the Earth's crust and the six most abundant elements in the Earth as a whole.
Earths crust- oxygen, silicon, alumminum, iron, calcium, sodium Whole earth- iron, oxygen, silicon, magnesium, nickel, sulfur
Define and contrast theory, law, hypothesis
Hypothesis- a tentative explanation based on observational data and expiriments Theory- a coherent set of hypotheses that explain some aspect of nature. Survived repeated challanges (must be testable) explanation of a phenomenon law- is the description of an observed phenomenon, statement based on repeated expirimental observations
Name and identify the different compositional and physical layers of the Earth
Mantle & core- heavey because iron and nickle, a dense core surrounded by a shell of silicate rich rock. mantle has an upper and lower seperated by transistion zone. sesmic waves indicate that earths outer core is liquid whereas its mantle is solid. The crust- composed of low density silicate which are rich in aluminum and postassium. the continental crust is less dense than either the oceanic crust or the mantle and so rides higher on the mantle the inner core- inner core can transmit both shear waves and compressional waves. the inner core is a solid metallic sphere suspened within the liquid outer core inner core- irons and nickle outer core is oxygen, sulfur, iron, and nickel mantle- oxygen, calcium, magnessium, silicon, aluminum and iron crust- oxygen, calcium, magnesium, silicon, aluminum, iron, and other
Classify and define different natural resources.
Natural Resources- Manage our natural resources in a way that continue to provide society with adequate energy, water and raw materials Reserve- are supplies that have already been discovered that can be exploited economically and legally at any time. vs. Resource- the entire amount of a given material. Including the amount for future use. Renewable- constantly producing new biomass, (water, wind, solar, lumber/trees) Non-renewable- geologic process produce much slower than we are using it up. Fossil Fuels (Coals, oil, natural gas)
Explain how scientific models allow for testing of ideas
a precise representation of how a natural process operates or how a natural system behaves. often formulated as a computer program that stimulates the behavior of a natural system. like a good hypothesis or theory, good model makes predictions that agree with observations
Define the principle of isostasy.
archimede principle- the weight of a fluid displaced is equal to the weight of the object displacing the fluid. the weight of a crustal block displaces an equal weight of mantle
Define the controls on the Earth's seasons
as earth revolves around the sun, the earth is on its tilt, when its winter the northern hemisphere gets more direct sunlight and vice versa
Determine the charge of an ion for atoms with atomic numbers between 1 and 20.
atomic numer is the # of protons+nuetrons, most likely not an even number but round it to the closet whole number (ask sage)
Define an ion and an isotope
ion- an atom or group of atoms that has an electrical charge , either positive or negative because of the loss or gain of one or more electrons isotope- one of two or more forms of atoms of the same element that have different numbers of neutrons and therefore different atomic masses
Explain the method that Eratosthenes used to calculate the diameter of the Earth more than 2000 year ago.
on summer solstice a well syene was filled with light indicating that the sun was directly overhead, where a pole in alexandria cast a shadow. Hefound that from the length of the shadow the two towns were 1/50 of the earths circumfrence about 7 degrees of 360. the measure between the two towns was 800km he calculate that earth was a sphere with a radius of about 6370 and the circumfrence was close to its value today of 40000km.
Define the characteristics of the different forms of seismic waves caused by earthquakes and how the speed of these waves can vary.
p waves- travel through solid rock at 6km/s, compressional vwaves because they travel through solid, liquid or gaseous materials. Push/pull waves s waves- half velocity of p waves. Shear waves that displace the material at right angels to their path of travel. Cannot travel through liquids or gas surface waves- confined to earths surface and outer layers. Velocity is slightly less than s waces. Rolling motion in the ground
Identify where the sun's radiation is maximum during different seasons.
radiation is most in December, then march, furthest in July, and then September
Using examples, describe or explain how the atomic structure and chemical composition of a mineral determines the physical properties of a mineral.
relate to some aspect of chemical composition or atomic structure minerals and rocks depend upon the process in the rockcycle, every mineral is a crystal. hardness, clevage, fracture, luster, color, density, crystal habit
Plot zones of high and low pressure on a map and explain why they form.
rising air= low pressure, sinking air=high pressure
Explain the factors that make up the Earth's greenhouse effect.
suns energy arrives as mostly radiation in visible wavelengths. Suns energy is then absorbed by earth. Earths radiant energy is release but as infrared wavelengths. Green house gasses absorb energy emitted by earth and radiate energy In all directions, come lost to space but half is reabsopred by earth doesn't have to do with sun when energy "hits" a molecule it will be "excited" but only if the energy is the right wavelength, energy is released in the form of head
Define the main parts of the "equation" of Earth's energy balance.
suns energy reaching earth - energy reflected = energy absorbed by the earth
Describe and plot the variation of ocean temperature and depth in the ocean.
surface waters are warm and well-mixed, deep waters are cold and dense
Define tectonic plate and define the relative plate movements for the three primary plate boundaries
tectonic plate- the lithosphere is broken into large plates that move around Divergent- plates move apart and create new lithsophere convergent-plates move togehter, oceanic lithosphere is recycled back into the matle, continental plates and deformed TRansform- plates slide horizatally past eachother