EARTH SCIENCE FINAL EXAM STUDY GUIDE JUNE 2014 - KEY

Minerals, Rocks, Geologic Time and Fossils

  1. Explain how each rock type forms:
  2. Sedimentary – weathering, erosion, compaction, cementation
  3. Metamorphic – intense heat and pressure
  4. Igneous – lava or magma cools and hardens
  1. Define:
  2. Weathering–breaks rock down into smaller pieces
  3. Bio-clastic – sedimentary rock made of pieces of organic material, such as fossil shells
  4. Foliated –having layers or bands of minerals
  5. Non-foliated –having a blocky crystal structure
  6. Intrusive –forms in the ground and cools slowly
  7. Extrusive –forms above ground and cools quickly
  1. Can any rock turn into any other type of rock? Explain.

Yes – the cycle does not need to go in any particular order

  1. List 2 examples of each rock type (igneous, metamorphic, sedimentary).

Igneous – obsidian, granite

Metamorphic – gneiss, marble

Sedimentary – coal, limestone, slate

  1. Would you expect an intrusive or extrusive igneous rock to have a larger grain size? Explain.

Intrusive – these rocks cool slower (the slower a rock cools, the larger the crystal grains will grow)

  1. Explain where on Earth you might find each rock type (igneous, metamorphic, sedimentary).

Igneous – deep in the ground, near a volcano

Metamorphic – VERY deep in the ground

Sedimentary – on the surface

  1. Describe the 3 types of metamorphism.

Regional – large regions/area of rock affected

Contact – rock came into contact with molten rock

Hydrothermal – rock changed because it came into contact with extremely hot water

  1. When looking at layers of rock, where is the oldest? Where is the youngest? Explain.

Oldest is at the bottom (youngest at the top) because the oldest layer has continued to get buried over time

  1. What is an index fossil? How are they useful?

An organisms that lived for a short time and has become extinct – it allows scientists to match rocks of the same age in different areas of the world

  1. In which type of rock are fossils found? Why?

Sedimentary – fossils can get buried and become a part of this rock; the processes that make igneous or metamorphic rocks would destroy any fossils

  1. How do you perform the test for mineral hardness?

Scratching the mineral with an object such as a nail or glass plate

  1. What is luster?

The way in which a mineral reflects light; luster can be described as dull, glassy, metallic, etc.

  1. Why should you look at a mineral’s streak instead of its color?

Streak is the color of a mineral in its powdered form. A mineral sample may have a different color due to weathering. Also, many different types of minerals have the same color, while some minerals are found to have a variety of colors. Streak is a truer test.

Mineral / Color / Luster / Streak / Hardness / Density (g/mL) / Chemical Composition
Biotite mica / Black / Glassy / White / Soft / 2.8 / K(Kg,Fe)3(AlSi3O10)(OH2)
Diamond / Varies / Glassy / Colorless / Hard / 3.5 / C
Galena / Gray / Metallic / Gray-black / Soft / 7.5 / PbS
Graphite / Black / Dull / Black / Soft / 2.3 / C
Kaolinite / White / Earthy / White / Soft / 2.6 / Al4(Si4O10)(OH)8
Magnetite / Black / Metallic / Black / Hard / 5.2 / Fe3O4
Olivine / Green / Glassy / White / Hard / 3.4 / (Mg,Fe)2SiO4
Pyrite / Brass yellow / Metallic / Greenish-black / Hard / 5.0 / FeS2
Quartz / Varies / Glassy / Colorless / Hard / 2.7 / SiO2
  1. Analyzing the table, which mineral has a density between 2-3 g/mL, soft hardness, and a color different from its streak?

Biotite mica

  1. How do fossils support the theory of plate tectonics (include at least two specific pieces of evidence)?

The same fossils found on Africa and South America show that they were once connected.

Fossils indicate that climates have changed over time (tropical fossils found in cold climates

  1. What is radiometric analysis and how can it help scientists?

Analyzes the amount of radioactive isotope in a rock. It can tell scientists the amount of time that has passed since that rock formed.

  1. Date the following formation from oldest to youngest (A-D including the fault!)

B & C, A, fault, D

  1. Write a scientific explanation that answers the following question: What is the youngest formation in this cross section (A-D including the fault)?

D

Use CER when writing response

Water, Oceans, and Climate

  1. Define each water cycle term:
  2. Condensation – process of changing water vapor to liquid
  3. Precipitation – water falling back to Earth (example: rain, snow)
  4. Evaporation – process of changing liquid water to gas
  5. Transpiration – special type of evaporation in plants
  6. Groundwater – water accumulated between rock and soil particles
  1. Where can you find liquid water in the atmosphere?

Clouds, fog

  1. List the areas of water storage on Earth. Which holds most of the water?

Lakes, rivers, oceans, groundwater, glaciers, atmosphere, plants, etc.

Oceans hold the most water

  1. When, in the water cycle, does water have a chance to enter the ground?

After precipitation occurs; it is called infiltration

  1. Define porosity.

The percentage of the total volume of a rock or sediment that consists of open spaces

  1. Define permeability.

The ability of a rock or sediment to let fluids pass through its open spaces, or pores

  1. How are porosity and permeability related?

As the porosity increases, the permeability also increases

  1. When, in the water cycle, does water collect as water vapor?

When it collects as clouds

  1. Define each water pollution term:
  2. Thermal pollution – dumping hot water into a water supply
  3. Biodegradable pollution – human or animal waste
  4. Chemical pollution – household or industrial chemicals dumped into the water
  5. Radioactive pollution – radioactive waste from mining
  6. Sediment pollution – soil and rock particles in the water which make it cloudy
  7. Nutrient pollution – fertilizers or other nutrients from farms or gardens washed into the water
  1. What is an aquifer?

Layers of rock that contain groundwater

  1. Does groundwater move? Explain.

Yes, it moves slower than a stream would flow

  1. Explain how glaciers formed the Great Lakes basin.

Glacial erosion carved out the lake basins; then glacial deposition filled in the basins with sediment and melt-water

  1. Explain how fecal coliform can be used as a water quality indicator.

Fecal coliform bacteria will not make you sick, but they indicate that other dangerous bacteria are present. A fecal coliform count >200 is considered unsafe.

  1. Explain what a high turbidity level means, in terms of temperature, dissolved oxygen content, and overall appearance.

High turbidity →high temperature, low dissolved oxygen, cloudy appearance

  1. From the data below, create a bar graph. Be sure to include a title and labels for your graph.

Sources of Pollution / Percentage
Industry / Manufacturing / 25%
Domestic / Household / 30%
Farming / Agriculture / 40%
Other / 5%
  1. What source produces the most pollution?

Farming/Agriculture

  1. What is the total percentage from the top 2 sources of pollution?

70% (Farming/Agriculture 40% + Domestic Household 30%)

  1. Which area (equator or poles) absorbs the most energy from the sun? Why?

The equator because the sunlight is most direct at the equator and least direct at the poles

  1. What causes the Coriolis Effect?

The rotation of the Earth

  1. Explain how ocean currents are deflected in the Northern and Southern Hemispheres because of the Coriolis Effect.

In the Northern hemisphere currents are deflected to the right or clockwise. In the Southern hemisphere, currents are deflected to the left or counterclockwise.

  1. Explain the difference between a maritime and continental climate.

Maritime is near a large body of water; continental is more inland. In the winter, maritime climates tend to be slightly warmer than continental. In the summer, maritime climates tend to be slightly cooler than continental.

  1. What is density?

A material’s mass per unit volume

  1. How does temperature impact density?

As temperature increases, density decreases.

  1. How does salinity impact density?

As salinity increases, density increases.

Weather, Severe Weather, and Climate Change

  1. Define:
  2. Air mass – a large body of air that has properties similar to the part of the Earth’s surface over which it develops
  3. Weather front – a boundary between two air masses of different temperature or moisture
  4. Dew point – measure of the moisture in the air; it is the temp the air must cool to in order to reach saturation
  5. Air pressure – the pressure that an air mass exerts on the Earth
  1. What are the components of weather?

Temperature, dew point, air pressure, wind direction, wind speed, humidity, cloud cover, precipitation, etc.

  1. Answer using the station model:
  1. Cloud cover – clear
  2. Wind direction – NW
  3. Wind speed – 15 knots
  4. Temperature: - 43°F
  5. Dew point – 18°F
  6. Air pressure – 150 = 1015.0mb
  1. Answer using the station model:
  1. Cloud cover – clear
  2. Wind direction – SE
  3. Wind speed – 10 knots
  4. Temperature: - 43°F
  5. Dew point – 33°F
  6. Air pressure – 001 = 1000.1mb
  1. Create a station model using the following information:
  1. Temperature 54°F
  2. Dew Point 41°F
  3. Wind Speed 15 knots
  4. Wind Direction E
  5. Air Pressure 1013.2
  6. Cloud Cover 25%
  1. Explain how each weather type forms:
  1. Hurricane – form when they gather heat and energy through contact with warm ocean waters; water evaporates and the moisture produces a storm
  2. Tornado – form when a thunderstorm meets horizontal winds which cause it to rotate
  3. Thunderstorm – Moisture: cloud formation & rain; Unstable air: relatively warm air rises rapidly; Lifting: from sea breezes and mountain interaction
  1. List 3 dangers of a thunderstorm.

Lightning, high winds, hail

  1. What are safety precautions that you should take during each type of severe weather :
  1. Hurricane – evacuate if needed, protect windows and glass with plywood, turn off utilities, have a supply kit
  2. Tornado – seek shelter immediately when a tornado warning is issued (underground or in an inside room, hallway, or closet), listen to the radio or watch TV for updates
  3. Thunderstorm – go inside and stay away from windows, doors, and porches; stay away from trees and out of boats; avoid plumbing fixtures and contact with electrical fixtures; stay off the phone
  1. What is the greatest threat to humans during a hurricane?

Storm surge

  1. What often forms from a thunderstorm super cell?

Tornadoes

  1. What scale is used to measure tornadoes? Hurricanes?

Tornadoes – Enhanced Fujita Scale

Hurricanes – Saffir-Simpson Scale

  1. If a hurricane has a pressure of 972mb and winds of 164km/hr, what category is the hurricane?

Category 2

  1. What would we call the storm if it is weaker than a category 1 hurricane?

Tropical storm

  1. What is climate?

The long-term (30 year) average of weather in an area

  1. What is global warming?

The increase of the Earth’s average surface temperature

  1. Are greenhouse gases a good or bad thing? Explain.

Both – we need them so the planet doesn’t freeze, but too much is causing global warming

  1. What are the main greenhouse gases?

Carbon dioxide, water vapor, methane, nitrous oxide, halocarbons, ozone

  1. How have carbon dioxide levels changed over the last century?

They have increased

  1. What is the main reason for this change?

Burning of fossil fuels