Earth Exam Study Guide

Exam 1:,m Unit 1. Earth’s Formation: Define stellar nucleosynthesis and explain its significance: - Stellar nucleosynthesis is when fusion in stars creates larger atoms. - This process is significant because it allows new elements that were not created in the big bang to form. Earth and planets forming: - Planets form by getting a lot of dust and gas close enough to each other to create a gravitational field strong enough to start fusion, fusion creates energy which stems the creation of stars. - The surface of earth initially magma ocean and then began to cool + solidify. - When Earth formed, the layers were not well defined as everything was molten rock. However, the Earth cooled and heavy materials like iron sank to form the core, and lighter materials like silicates rose to form the crust. Unit 2. System Earth: Makeup of Earth: - Crust: oxygen (O), silicon (Si) and aluminum (Al). - Earth as a whole: iron (Fe), oxygen (O) and silicon (Si). - Layers of Earth (inside -> out): o Inner core: completely solid (smaller then outer core) o Outer core: liquid o Mantle (3 parts) (takes up most space)  Mesosphere lowest layer  Aesthenosphere 2 nd lowest layer  Both act as conduction ovens o Lithosphere is rigid + acts a conduction oven to the rest of the earth o Crust  Continental + Oceanic (continental is thicker) Magnetic fields of earth - Generated by the motion of molten iron in Earth's core, the magnetic field protects our planet from cosmic radiation and from the charged particles emitted by our Sun. Unit 3. Plate Tectonics: Seafloor Spreading: - Seafloor spreading is when divergent plate boundaries move away from each other in the ocean. Mantle flows to this point and cools forming new crust. There are 3 proofs of this: o Deep sea trenches o Fracture zones (narrow, vertical cracks in ocean surface) o Seamounts (volcanic islands) Divergent, Convergent and Transform: VOLCANOES EARTHQUAKES TOPOGRAPHY

DIVERGENT (going away) Volcanic activity Shallow earthquakes Oceanic spreading ridges, red sea rift, (ridges and rifts) CONVERGENT (coming together) one plate dives under another resulting in a line of volcanoes on the overriding plate, 80% of earthquakes take place on convergent boundaries Caribbean islands, Himalayan mountains, Appalachian Mountains, (large risings in ground or ocean) TRANSFORM (slide sideways) Little to no magma available at plate boundaries meaning that volcanoes do not typically form Most dangerous and largest earthquakes (San Andrea's fault is transform earthquake) Long ridges separated by narrow valleys (much of California is on a transform fault) - Connecticut was part of Africa but plate tectonics rifted it away and made the Atlantic Unit 4. Minerals: The major class of rock forming minerals are silicates (silicon and oxygen) Examples: Quartz, Feldspar, Mica, Clay minerals, Olivine, Garnet, Pyroxene, Amphibole, Beryl, Hemimorphite, Epidote WHY Minerals form o Atomic bonding + size constraints o Specific minerals form based on pressure temperature and composition o Atoms bond and fit together in minerals to minimize potential energy of the system o Nature trends toward minimizing energy and attaining equilibrium HOW minerals form o precipitation, dissolved in aqueous solution -> solid o solidification, magma or lava -> solid o diffusion, solid -> solid o De-sublimination, vapor - > solid o biomineralization there are classifications of rock forming minerals o Silicates, Carbonates, oxides, halides, sulfates, sulfides, native éléments Unit 5. Rocks: - 3 ways to melt a rock o Increase temp o Decrease pressure o Add volatiles (ex. Water) – COMPOSITION! (put in the melt chart) once you cross the solidus, melt forms

- - - Unit 6. Fossils + Life on Earth: When and where did the first life form? Life on Earth is about 3.7 billion years old. It formed at deep sea hydrothermal vents. Here, seawater meets magma to form microorganisms. Stromatolite and banded iron formation: - Banded iron formations form when iron is oxidized and forms rust. - Stromatolite are layers of bacteria trapped in layers of sediment - These are significant because they are proof of the first oxygen on Earth. Stromatolite are the first photosynthesizing things on Earth. Unit 7. Sediments: - Physical vs Chemical Weathering o Physical: breakdown of rocks and soil through mechanical effects o Chemical: breakdown via chemical reactions - Wind + Gravity + other agents can move clastic sediment o Sediments are deposited when the forces of gravity overcome those trying to move them o As energy of transportation decreases smaller material is deposited How do clasts (a kind of sediment) change? They get smaller, rounded, and well sorted as they move

Identify the depositional environment of common chemical and biochemical sedimentary rocks (rock salt, travertine, coal, chalk, limestone). - rock salt = large enclosed bodies of seawater and desert- - travertine = springs - coal = delta, swamp - chalk =deep marine - limestone = ocean, sometimes lake Unit 8. Time:  Angular unconformity - uplift and erosion -> limestone folded and eroded o Flat layers overly tilted layers  Disconformity – uplift and erosion -> deposition of new sediment o Flat layers overlie flat layers  Nonconformities – uplift and erosion exposed igneous metamorphic rock -> sediment deposited on topz - Contact metamorphism: magma intrudes and changes rock. Intruding magma is younger - Cross cutting relationships (intrusions) means that the intrusion is youngest thing there - Compressive stress = folding = converging plates Unit 9. Mass Extinction - Warming of the Earth's climate and associated changes to oceans caused end-Permian extinction - MASS EXTINCTIONS INVOLVE COMPOUNDING EFFECTS - End-Permian Mass Extinction o 1. Carbon Dioxide (volcanic emissions) o 2. Warming o 3. Ocean acidification o 4. Ocean anoxia o 5. Desertification o 6. Climate Change o 7. Habitat loss o 8. Acceleration of "normal" extinction mechanisms o = 96% of all species extinct - heightened volcanism associated with the Deccan Traps and the Chicxulub asteroid impact caused the end-Cretaceous extinction Unit 10. Climate - The Greenhouse effect o Radiation from sun travels to earth o Half reflected or absorbed by clouds and atmosphere o Rest reaches earth and absorbed by ocean and land o Earth releases heat (infrared light towards space) o Some of this heat passes directly thru atmosphere o Most is captured by ghg and heats atmosphere - Volcanism vs weathering

Exam 2: Unit 11 – Tectonic Landforms · Identify the locations of the largest mountain ranges on Earth. · Explain the tectonic processes that cause mountain ranges to form. · Explain why Earth’s tallest peak depends on how you measure it. · Locate the youngest and oldest mountains in the US and North America. · Recall the timing and causes of the mountains that formed the bedrock in Connecticut. · Recall the features of ductile deformation that develop when mountains form and where in the crust ductile deformation occurs. · Define a fold and identify the oldest and youngest layers of rock in a fold (anticline vs. syncline). Anticline: Looks like an arch. The bed dips away from the hinge. Oldest rock at hinge Syncline: Looks like a trough. The bed dips towards the hinge. Oldest rock away from hinge · Identify, sketch, and describe the different types of faults that occur in the crust and the tectonic environments in which each are common. - Strike: Horizontal line on an inclined surface - Dip: Inclination or slope of surface (measured from horizontal) - Dip Slip Fault: Fault moves along the dip direction. Normal moves down, reverse moves up - Strike Slip Fault: Move alongside one another like transform plates

· Explain the significance of the brittle-ductile transition zone in the crust and how the crust deforms brittlely and ductility when experiencing tectonic stresses. - At shallow depths, the crust is brittle and will break apart. There is a transition zone where the crust becomes ductile and solid but squishy. The deeper and more stress you have, the crust irreversibly changes from brittle to ductile. Cracks and fractures at shallow depths - Unit 12 – Mass Movements · Define the term mass movement. Downward movement of a solid, discontinuous or continuous mass under the influence of gravity · Define the term angle of repose and explain the relation of this concept to mass movement - Angle of repose: Max angle which a granular material can be piled before it falls and moves - Once we surpass this angle, we will have a mass movement - Most materials have an angle of repose <= 45 degrees · Identify at least four physical processes that can cause a mass movement. - Uplift (changing slope angle) - Removing matter from bottom or adding it to top - Changing water content (changing angle of response) - Shock/jolts such as earthquakes · Distinguish between three common types of mass movements: falls, flows, and slides. - Slides: Slide on top of basal slip surface that may be planed or curved - Falls: Free falls with downward vertical movement - Flows: · Define creep, slumps and explain whether they are examples of falls, flows, and slides. - Creeps: Top layers move down slope; large amount of ground material are moved. Very slow. - Slumps: Like a normal fault but slower and caused by gravity instead of extension - Both are examples of slides

Unit 14 – Oceans and Coasts · Describe the main bathymetric features of the deep ocean and be able to order them from shallowest to deepest. · Define a manganese nodule and how they relate to deep ocean sedimentations and natural resource exploration. Nodules on the sea floor are rich with manganese. The slowest sedimentation takes place where these nodules form. Take millions of years to grow and are not a renewable resource. · Relate seafloor sediment thickness to active and passive tectonic margins. Sediment piles up at passive margins, where there is no plate boundary/subduction therefore having thicker sediment. · Passive Vs Active Margins: - Passive: sediments build up, more deposition - Active: rockier shores, more erosion FOR NOTES SHEET (IS A MATCHING QUESTION) · Define thermohaline circulation and explain its role in regulating climate conditions across the globe. - Thermohaline circulation is the ocean conveyor belt of heat and salinity. These things influence the density of the water, as warmer and fresher water is less dense. A molecule of water can take about 1500 years to complete the cycle. - The oceans globally absorb heat and gases and carry heat from the equator to the poles. Locally, they moderate temperatures and influence patterns of precipitation.

- · Explain how the following factors have shaped New England’s coastline: tectonics, glaciers, wave action, erosion, deposition, and sea level change - Wave Action o Negligible water movement at depths below ½ wavelength o Wavelength increases, velocity decreases and height increases. - Sediment Deposition and Erosion o Waves crash at an angle to the coastline. o The sand washed up on shore is deposited at the same angle. - Tectonics, Glaciers, and Sea level change o Connecticut was under ice about 30,000 years ago. o The glacier made the shorelines more extended than they are now, and erosion will eventually make them retreat further than they are now. o 20,000 years ago, the glacier retreats and you can start to see the coast of the Long Island Sound o 5,000 years ago, the shore looked the same as it does today. o The bigger glaciers push down the crust and make bulges around it. Deglaciation causes uplift where the glacier was as the weight gets lifted off Unit 15 – Deserts · Explain the relationship between latitude and deserts in terms of global atmospheric circulation patterns. - Deserts form because evaporation > precipitation (except in polar deserts) - As latitude goes up or down with respect to equator, deserts go from tropical to polar - Most deserts around 30 degrees latitude · Explain why deserts form on the leeward side of mountain ranges. - Rain shadows. The rain does not pass over mountains and leaves the other side very dry · Explain why deserts can occur along coastlines. - Cold air descends, warms up, absorbs moisture - Coasts near cold ocean currents

· Identify the landforms/features shared between continental and alpine glaciers. - Both types of glaciers will change the topography by slow moving erosion · Recall the influence of Milankovitch cycles on continental glaciation. The climate cycle changes every couple thousands of years, making the Earth cooler. During a cool period, the glaciers did not completely melt in the summer. The white snow reflected light allowing more snow to form without melting, forming more glaciers. · Define/describe the following features formed from glacial erosion: U- shaped valleys, hanging valleys, cirques, horns, arêtes, and medial moraines, and roche moutonnées. - U-shaped valleys: U shaped valley carved by glaciation - Hanging valley: Hangs over a u-shaped valley - Cirques: Bowl shaped valley formed by a glacier - Horns: Pointy feature of glacier - Aretes: Thin, jagged crest that separates 2 adjacent glaciers - Medial moraines: Where 2 lateral moraines meet. Looks like a divided road - Roche Mountonnees: Asymmetrical bump. One side smoothed as glacier goes over it, other side plucked apart as glacier passes it. Steeper side is where downflow happened. · Define/describe the following features formed from glacial sediment deposition: till, terminal moraines, drumlins, kettles, eskers, kames. - Till: The sediment deposited by glaciers. Poorly sorted - Terminal Moraines: Sediment deposited at the furthest point of advance in a glacier - Drumlins: Asymmetrical hills formed by glaciation. Steeper side is where up flow happened. - Kettle ponds: Glaciers leave ice behind, and they get buried. The ice melts and forms small ponds - Eskers: Wormy ridges that trace the direction of mountain water stream flowing underneath glacier. Sediment will accumulate under these - Kames: Steep mound of sand and gravel formed by glaciation -

· Identify the glacial landforms that are present on the UConn Storrs campus and the neighboring segment of the Fenton River. · Provide examples of concerns that relate to glaciers, water resources, and modern climate change. - Flooding, less water, land erosion, warming streams, unstable ground Make categories of geologic features with key words: - Brittle vs Ductile - Erosion vs deposition - Close to source VS far from source - Active Vs Passive margins - Glacier things - Desert Vs Wetter o Wind shapes deserts - Sandy vs Rocky Shorelines Exam 3: Unit 17 – Energy & Mining · Define the terms porosity and permeability and explain their significance in terms of extracting oil and gas from the ground. - Porosity: Proportion of material made up of empty pore space that can fill with air or water - Permeability: Capacity of water to flow through earth materials. Grain size squared times porosity squared. - Wherever we extract the oil from the ground must be much less permeable than the layers beneath it. Oil will sit under gas, so now we can get an idea of where we they sit in the crust · Define the terms seal rock, reservoir rock, and source rock in terms of oil and gas resources. - · Explain how folds, faults, and unconformities can affect the formation of oil and gas reserves. - Helps people find the best spot to drill oil · Explain the process that form oil and gas and compare and contrast that with the process that forms coal. -

- Bottom water anoxia: Lack of dissolved oxygen which can cause fish to choke - Mississippi River: Starving deltas of sediment that allow them to sustain their size and grow · Explain the potential for major dam construction to cause political conflict and land subsidence. - Political conflict arises because damns that run through more than one country/state can control or limit the water flow of another - Subsidence is when land moves below sea level. An example is when a dam in Mass flooded 4 towns to be completed · Describe the various consequences associated with over-pumping and contamination/pollution of groundwater. · Recall how freshwater is used by humans on a U.S.-wide and global scale, and what the environmental impact is of human freshwater consumption. · Define the terms porosity and permeability. - Porosity: Proportion of material made up of empty pore space that can fill with air or water - Permeability: Capacity of water to flow through earth materials. Grain size squared times porosity squared. · Explain how these porosity and permeability might vary in different earth materials. - Aquifers have high porosity and permeability. These tell where glaciers were, because the sand and gravel left behind as till soaks up groundwater · Explain what the water table represents, and how its depth might vary in humid vs. arid regions. · Explain aquifers, both confined and unconfined/open, in terms of variable porosity and permeability of the local substrate. - A confined aquifer is trapped underneath a confining layer, whereas an unconfined one would be above · Explain what causes groundwater to flow. - The hydraulic head, which is the pressure underneath a column of groundwater · Describe the various consequences associated with over-pumping and contamination/pollution of groundwater. - Contamination - Over extraction: water quality deteriorates, wells dry up, - Too many wells can draw contaminants in their direction instead of the groundwater flow - Groundwater flowing through rock does not filter out bacteria. But through sand and gravel does a better job of filtering - Over pumping lowers the water table, rendering shorter wells useless

· Recall how freshwater is used by humans on a U.S.-wide and global scale, and what the environmental impact is of human freshwater consumption. Unit 19 – The Anthropocene · Define the Anthropocene. Unit of time where there is global evidence that Earth’s system processes, which will be recorded in rocks, are now altered by humans · Recall the period, era, and eon that the Anthropocene belongs to in the geologic time scale. Phanerozic eon, Cenozoic era, and after Holocene epoch · Explain why scientists say that the Anthropocene began in the year 1950. - WWII saw the emergence of nukes that put radiation in the environment - Industrialization and fossil fuel usage go up - The Great Acceleration · Define the Great Acceleration and describe the environmental changes experienced during the Great Acceleration. - In the 1950s the production and consumption of aluminum, concrete, plastics, and synthetic fibers increased drastically - Population growth increased need for food and fertilizer use · Recall the particular isotopes that scientists use to distinguish the Anthropocene from the Holocene. - Less fossils due to extinction - Deforestation and unconformities - River environments become lake environments - Acidification - Spike In radioactive isotopes and microplastics · Distinguish between the regional and global Anthropocene and provide examples of both. Regional: - Only happens in a specific region or ecosystem - Trinitite, which is a glassy residue formed in areas nukes are tested Global: - Affects entire Earth - Carbon 14 from nuke detonation

· Recall the factors that can affect the level of hazard associated with earthquakes. - Infrastructure - Weak vs strong sediment - Water content of soil - Quality of building construction - Citizen awareness and preparedness · Define the term liquefaction and describe the type of substrate that is likely to experience this process. - Loosely packed sediments lose their strength in response to shaking - Friction keeps the grains together, but when the earth shakes, we lose friction and that soil becomes liquid-like, and things sink in it · Define the term tsunami and recall the types of processes (not just earthquakes!) that can cause one to occur. - Initiated by massive water displacement. · Explain what happens to a tsunami as it approaches the coast from the deep ocean. - In the open ocean, they are fast with small wave heights and long wave lengths - As they get to land, they slow down, get larger, and shorten in wavelength - Affect the depositional environment of clastic sediments Unit 21 – Climate Hazards · Explain the relationship between climate hazards and radiative forcing in the climate system. - The avg amount of radiative forcing is increasing - More energetic climate system - Creates hurricanes, storms, flooding, wildfires, tornadoes · Explain the effect of human activity on radiative forcings in the climate system. - Positive forcings = warmer climates, negative forces = cooler climates - Carbon dioxide is the biggest factor in climate warming · Describe the effect of climate change on intensity, frequency, and locations of wildfires. - All of these factors will increase - Increased summer temps which lead to drought conditions and less cooling at night · Describe the effect of climate change on intensity, frequency, and locations of flooding. - All of these factors will increase

- Wetter grass has less flooding as it is more permeable. So increased temps mean drier grass and a higher chance of flooding · Describe the relationship between climate change and tropical storms. - Climate change makes storms form faster and move slower, which makes it hard for people to prepare for/ live through · Describe the effect of climate change AND human land use on the processes that can trigger landslides. - A little water will stabilize land. Increased temps means there will be either a lot or a little water, neither which will hold well · Explain the significance of the jet stream, how it influences weather, and how it is affected by climate change - Unit 22 – Futures · Define the terms cycle, trend, and model. - Cycle: - Trend: extrapolations of changes in past and present - Model: Quantifying the data. Think of it as telling the story · Explain how cycles and trends are used in models to predict what will happen to Earth in the future. · Explain and provide examples of why human activity is one of the largest sources of uncertainty in our predictions of the future. - There is a margin of error that has to be taken into account - The farther you try and predict the future, the more uncertainty there is as things you don’t expect could pop up · Recall the geologic processes we expect to affect the Earth 100, 1000, 10,000, 1 million, and 1 billion years from now - Orbital cycles (10,000 – 100,000 years) - Tectonic processes (1 million – 1 billion years) - Cooling of Earth’s core (91 billion years) - Sun’s life cycle (ends in 1 billion years)