Final Exam - Earth Systems - Second Semester
Terms in this set (184)
What is fossil?
Remains of an ancient organism or its activity
What kinds of rocks are fossils found in?
What help determine the absolute and relative ages of rocks?
What provides clues to past geologic events, climates, and evolution of living things?
What are an indicator of an area's ancient environmental conditions and climates?
Why do fossils not form in igneous rocks?
Igneous rocks are too hot.
Why do fossils not form in metamorphic rocks?
Metamorphic rocks require too much heat and pressure to have fossils.
Name some kinds of Trace Fossils.
Trace fossils include Tracks, Trails, Footprints, Burrows, and Borings
True or False: Most multicellular life appeared less than 500 million years ago.
TRUE! Most multicellular life appeared less than 500 million years ago.
What are the best indicators of an area's ancient conditions and climate?
TYPE and DISTRIBUTION of FOSSILS are the BEST indicators of an area's ancient conditions and climate.
What is the Law of Superposition?
In an undisturbed rock column, the oldest rocks will be on the bottom and the youngest ones on top.
True or False: Fossils provide important geologic information by revealing only the absolute age of rocks.
FALSE! Fossils provide important geologic information by revealing BOTH the absolute and relative ages of rocks.
What are the beginnings and endings of Geologic eras defined by?
Beginnings and ends of Geologic eras are defined by major changes in life forms based on fossil evidence.
Would we expect to find similar or different fossils grouped in rocks from the same time period in history?
Rocks grouped within each time period contain SIMILAR fossils.
Name the three eras in the Phanerozoic eon from oldest to youngest.
Paleozoic, Mesozoic, Cenozoic
Name some characteristic of the Precambrian Era.
Earth was forming and cooling, heavy bombardment of planet by asteroids, continents were forming, first life - single celled organisms, first ocean, some small multi-cellular organisms
Name some characteristic of the Paleozoic era.
Age of fishes, first marine life, first fishes, first amphibians, first land plants, first reptiles, first forests.
Name some characteristic of the Mesozoic era.
Age of Reptiles, dinosaurs rise and fall, first birds, first small mammals, first flowering plants
Name some characteristic of the Cenozoic era.
Age of Mammals, first placental mammals, first large mammals, first humans
Using the chart at the END of your Index Fossil notes (#4), answer this: You have rock that you know dates from the Ordovician period. Name one fossil you would expect to find in it?
Bathyurus OR Tetragraptus
What is an Index Fossil?
a fossil that scientists use to date rocks; they are found widely scattered in rocks over a large region existed for a short geologic time.
True or False? A fossil must be ABUNDANT, UNCOMMON, DISTINCTIVE, and LIMITED in order to be considered an index fossil.
FALSE! An index fossil must be:
Abundant - distributed over a wide area.
Common - large numbers within a rock layer.
Distinctive - easy to recognize.
Limited - from a short, specific geologic time span.
Can an index fossil be used to date sedimentary rocks in two different places on Earth?
Index fossils can be used to date rock layers found in widely separated areas. They also can help determine the age of sedimentary rock.
Name some Index Fossils that we learned.
Trilobite, Ammonite, and others listed in the chart
What can fossils tell us about their environment?
Marine (Ocean): If the fossil is similar to a current ocean organism, it probably lived in the ocean. Thick shelled organisms lived in shallow water and thin-shelled organisms lived in deep water.
Fossils of ocean/marine organisms have been found in the Rocky Mountains. How is this explained in Earth Science?
The Rocky Mountains were not always mountains and were once much lower and the land was part of an ocean.
What is a Mass Extinction Event?
A catastrophe for the world's living organisms, a rapid event (shorter than 10,000 to 100,000 years), and a significant part of all life on Earth became extinct.
Which mass extinction event was the biggest, when was it, and what is the percentage of organisms that died?
The THIRD mass extinction event - the "Great Dying" - was at the end of the Permian Period (end of the Paleozoic Era). Almost 96% of all organisms were killed
What are the two theories concerning the cause of the fifth mass extinction event - the event that killed the dinosaurs?
The METEORITE theory (meteorite hit near Mexico) and the VOLCANO theory (increased volcanic activity on Earth).
What happens to the biodiversity of life after a mass extinction event?
Surviving species take over vacant habitats and resources. New species develop and fill in vacant habitats. As a result biodiversity increases.
TRUE or FALSE? The fossil record shows us that fossil species can disappear and then reappear many years later.
FALSE! Fossil species appear and disappear throughout time but they cannot disappear and reappear many years later.
What causes the change in organisms over time?
Changes in Earth's environment over time results in changes in organisms.
TRUE or FALSE? Fossil evidence shows life becomes less complex over time.
FALSE! Fossil evidence shows life becomes MORE complex over time.
Who first proposed Natural Selection?
What is Natural Selection?
Natural Selection describes the process by which organisms that are best suited to the environment are most likely to live and pass on their genes (traits). It is a Gradual process. Organisms with less suitable traits fail to survive and/or pass on their genes.
TRUE or FALSE? Life responds to environmental changes.
TRUE! Environmental change is any change in an environment to which an organism must adapt. Can be gradual, ex: mountains form and can be quick, ex: floods volcanoes. Environmental change forces the organism to adapt.
What does the fossil record show us about the development of organisms over time?
The fossil record shows a succession of incremental development from one species to another.
Where does most of the evidence for evolution come from?
The Fossil Record: Much of the evidence for the evolution of life-forms on Earth has been obtained by examining fossils preserved in rock layers.
What is the Principle of Original Horizontality?
sediments are originally deposited horizontally under the effect of gravity
What is the Principle of Superposition?
a principle holding that the youngest layer on top and the oldest on the bottom
What is the Law of Cross-Cutting Relationships?
Whatever is crossing over a set of rocks is younger than that set of rocks.
What is the Principle of Lateral Continuity?
Sedimentary rocks are laterally continuous over large areas.
Describe an unconformity.
An unconformity is an erosional surface between two rock units or layers.
What is a Fault?
A fault is the breaking of rock - earthquakes occur along fault lines. This is an example of a cross-cutting relationship.
Describe an angular unconformity - be able to recognize a diagram like on Review #9.
Angular unconformities must have rocks below the unconformity line that are tilted.
Describe a disconformity - be able to recognize a diagram like on Review #9.
Disconformity is an unconformity that has erosion between two layers of sediment. There might even be a layer missing
Describe a paraconformity - be able to recognize a diagram like on Review #9.
Paraconformity is an unconformity that has little or no evidence of erosion because the layers are parallel and some are missing.
Describe a nonconformity - be able to recognize a diagram like on Review #9.
Nonconformity is an unconformity where igneous or metamorphic rock is exposed and weathered, then sedimentary rock builds above it.
In an undisturbed rock column the layers on the bottom will be the oldest and the youngest rocks will be on the top. What is this called?
The Law of superposition
Layers of sediment are originally deposited horizontally under the action of gravity. What is this called?
The Principle of Original Horizontality
Sedimentary rocks are laterally continuous over large areas. What is this called?
The Law of Lateral continuity
A principle holding that an igneous intrusion or fault must be younger than the rocks it intrudes or cuts across. What is this called?
The Law of Cross Cutting Relationships
An example of a structure that cross-cuts a geologic column.
Structural relationships may be faults or fractures cutting through an older rock.
An example of a structure that cross-cuts a geologic column.
Intrusional relationships occur when an igneous magma is intruded into pre-existing rocks.
An example of a structure that cross-cuts a geologic column.
Stratigraphic relationships may be an erosional surface (or unconformity) cuts across older rock layers, geological structures, or other geological features.
The geological processes that took place in the past are generally similar to those that occur now.
What does Conglomerate sedimentary rock tell you about the original environment?
Conglomerate sedimentary rock is composed of rounded gravel, pebbles, cobbles, or boulders along with smaller rock pieces and shows an extremely high energy of transport like a fast moving river or a glacier.
What does Sandstone tell you about the original environment?
Sandstone is composed of sand and indicates moderate energy of transport. form a beach or a desert.
What does Shale tell you about the original environment?
Shale is composed of clay sized particles and indicates a low energy of transport like a calm marine/ocean or muddy environment.
What does Limestone tell you about the original environment?
Limestone is a sedimentary rock rich in calcite made for the shells of marine animals. Limestone forms in quiet shallow ocean water beyond the beach (sandstone) and beyond the near shore (shale) environments.
What does Extrusive Igneous rock tell you about the original environment?
Extrusive Igneous Rock refers to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out (extrudes) onto the surface as lava and may also be found intruding into older rock formations.
When interpreting a rock column, what type of rock would you need to see to assume that there was once a marine or ocean environment?
Sandstone - beach;
Shale - shallow sea;
Limestone - ocean
When interpreting a rock column, what type of rock(s) would have no fossils at all
Igneous and metamorphic rocks would have no fossils at all -
If a fault cuts through some layers of rock and the top layer on one side is thicker than the same rock layer on the other side, why is this?
The thinner layer has been exposed to more erosion than the other side.
What kind of energy is associated with conglomerate rock?
High energy either from a fast moving river or a glacier.
What kind of energy is associated with shale rock?
Low energy is associated with shale as it indicates a shallow sea or muddy environment.
What kind of energy is associated with sandstone rock?
Mid energy is associated with sandstone rock from slower moving water, beach, or windy desert.
What kind of energy is associated with limestone rock?
Low energy is associated with limestone rock as it indicates an ocean or marine environment.
How is a dome formed?
Rock is uplifted and then partially eroded. Older rock in the middle.
How is a basin formed?
Rock is uplifted away from a point and forms a basin. Younger rock is in the middle.
If you see a wavy line on a geologic cross section, what does it mean?
It means that there is an unconformity there.
Look at diagram on review #10 and be able to put the rocks in the correct order.
Oldest: A, B and N, C, D and M, E and L, F and K, J, I, G, H is youngest.
Look at diagram on the left side of review #11 and be able to indicate the age of the intrusion.
The intrusion is the youngest since it cuts through every layer of rock.
Look at diagram on the right side of review #11 and be able to indicate the relative age of the unconformity and tell what kind of unconformity it is.
The unconformity is older than layer B but younger than layer C. It is an angular unconformity.
What type of fossils might you find in the Paleozoic era age rock?
early fish, trilobites
What type of fossils might you find in the Mesozoic era age rock?
Dinosaurs, early birds, reptiles, early small mammals, ammonites
What type of fossils might you find in the Cenozoic era age rock?
large mammals, early man
If you find trilobite and fish fossils in the same rock layer, what might you think was the environment that the sediment that made the rock was formed in?
Ocean or marine environment.
If you find a dinosaur bone, or mammal fossil, what might you think was the environment that the sediment that made the rock was formed in?
Land or swampy environment
What was the predominant life forms of the Paleozoic era?
What was the predominant life forms of the Mesozoic era?
Reptiles, particularly dinosaurs
What was the predominant life form of the Cenozoic era?
Age of mammals
If you were looking for evidence of caves, what type of rock would you look for?
Caves are formed only in sedimentary rocks.
If you see metamorphic rock on the surface of the earth, what does that tell you about that rock?
Metamorphic rock is formed deep within the Earth's crust and must have been uplifted to get to the surface.
What is the lowest layer of the atmosphere where weather occurs?
As elevation ___________, air pressure decreases.
increases (As altitude increases)
What is the source of energy for the atmosphere?
As sunlight comes into the Earth's atmosphere, what three things can happen to it?
It can be reflected back to space (30%), absorbed by the atmosphere (20%) and it can be absorbed by the surface - land or ocean (50%).
What is INSOLATION?
The amount of solar radiation reaching a given place on the Earth.
Which part of the Earth gets the most direct insolation?
The equator has the highest angle of insolation (90 degrees).
Which part of the Earth gets the least direct insolation?
The poles have the lowest angle of insolation (30 degrees)
What determines the amount of solar insolation received?
The latitude on the Earth determines the amount of solar insolation received.
Does the amount of sunlight coming from the sun change?
No, the amount of sunlight does not change. It just feels less hot at the Earth's poles because it is spread out over more of a distance.
Which area on Earth gets the most direct sunlight?
The equator gets the most direct sunlight.
Which area of Earth gets the most indirect sunlight?
The Earth's poles get the most indirect sunlight.
Warm air ______, cool air sinks.
As air rises, it cools and _______
Describe the air temperature, spinning, and weather of an area of low pressure.
Air temperature is warm; It spins counterclockwise; The weather is wet.
What type of air pressure creates clouds, Low or High?
Low Pressure creates clouds.
Describe the air temperature, spinning, and weather of an area of high pressure.
Air temperature is cooler; It spins clockwise; The weather is clear and dry.
Air moves from _____ pressure to _____ pressure.
Air moves from HIGH pressure to LOW pressure.
What is wind?
Wind is air movement due to changes in air pressure.
What causes the main direction of wind currents?
Convection currents due to the uneven heating of the Earth's surface.
On Earth, ____ air rises at the equator and ____ air sinks at the poles.
On Earth, WARM air rises at the equator and COLD air sinks at the poles.
What is the CORIOLIS EFFECT?
The Coriolis Effect is where winds are deflected or turned on the Earth's surface because the Earth spins on its axis.
Name the wind belt that occurs between 0 and 30 degrees north and south of the equator.
The Trade Winds (Northeast and Southeast)
Name the wind belt that occurs between 30 and 60 degrees north and south of the equator.
Name the wind belt that occurs between 60 and 90 degrees north and south of the equator.
The Polar Easterlies
The area where the air rises at the equator and there are no winds is called the ____.
The area where the air sinks at 30 degrees latitude and there are no winds is called the ____.
What is the jet stream?
A wind that flows at great speeds in the stratosphere.
What is an AIR MASS?
A large volume of air with similar temperatures and dew points throughout.
There are two ways that air masses are described. What are they?
They are described by temperature and moisture.
What are the two ways words used to describe the moisture of an air mass?
Continental (dry) and Maritime (moist)
What are the three ways words used to describe the temperature of an air mass?
Tropical (warm), Polar (cold), and Arctic (very cold)
How would you name an air mass that is dry and warm?
Continental Tropical, cT
How would you name an air mass that is cold and wet?
Maritime Polar, mP
What do we call the boundary where air masses collide?
What is a COLD front?
Forms where cold air moves towards warm air. Creates rain storms.
What is a WARM front?
Forms where warm air moves towards cold air.
In the summer, air over the ____ is warmer than the air over the ____ during the day.
In the summer, air over the LAND is warmer than air over the WATER during the day.
In the summer, ____ pressure forms over the land during the day.
In the summer, LOW pressure forms over the land during the day.
What kind of breeze is formed during the day at the beach.
A SEA BREEZE is formed because air is pulled from the high pressure over the water to the low pressure over the land.
Ocean currents help regulate Earth's climate by storing and transporting ____.
Ocean currents help regulate Earth's climate by storing and transporting HEAT.
Ocean currents are controlled by what three factors.
1. Air currents - prevailing winds ; 2. Earth's rotation - Coriolis; 3. Location of continents - land masses act as barriers
What is an ISOBAR?
A line drawn on a weather map or chart linking all points of equal or constant pressure.
Air moves clockwise and out from ____ pressure.
Air moves clockwise and out from HIGH pressure.
Air moved counterclockwise and into ____ pressure.
Air moved counterclockwise and into LOW pressure.
If the isobars are close together on the weather map, the area is experiencing ____ winds.
If the isobars are close together on the weather map, the area is experiencing STRONG winds.
If the isobars are not very close together on the weather map, the area is experiencing ____ winds.
If the isobars are not very close together on the weather map, the area is experiencing WEAKER or CALMER winds.
How can you determine how winds are flowing in an area on a weather map?
You can determine how winds a flowing in an area by looking at the high and low pressure areas.
What is orographic lift (rainshadow effect)?
Orographic lift (rainshadow effect) is when an air mass is forced from a low elevation to a higher elevation as it moves over rising terrain.
What happens on the WINDWARD side of a mountain?
Air rises, cools, and forms clouds
What happens on the LEEWARD side of a mountain?
Air sinks, warms, and clears.
What is the tilt of the Earth?
The tilt of the Earth is 23.5 degrees
Are the seasons the same at the same time in the Northern and Southern hemisphere?
No. When it is winter in the Northern Hemisphere, it is summer in the Southern hemisphere.
What causes the seasons of Earth?
The Earth's tilt causes the seasons because the sun is higher in the sky during summer and lower in the sky during winter.
As you get further away from the equator, the days become ____ in the summer.
As you get further away from the equator, the days become LONGER in the summer.
What are ocean currents controlled by?
Ocean currents are controlled by air currents, the Earth's rotation (Coriolis Effect), and the location of continents.
Why does Ireland have a warmer climate than Newfoundland even though they are both at the same latitude?
Ireland has the Gulf Stream carrying warm water going by it and thus warm air towards it. The Labrador Current which is a cold water current goes by Newfoundland.
What is El Nino?
El Nino is a climate cycle in the Pacific Ocean where the Eastern Pacific Ocean (west coast of the United States) warms more than usual. It causes wet winters in the Southeastern United States.
What is La Nina?
La Nina is a climate cycle in the Pacific Ocean where the Western Pacific Ocean ( eastern shores of Asia) warms more than usual. It causes a greater hurricane activity in the Atlantic Ocean.
What are the three climate areas of the Earth?
Tropical, Mid Latitudes/Temperate, and Polar
What is the average precipitation and temperature for a desert climate?
A desert climate has average yearly rainfall of less than 25cm and a large range in temperatures from hot days to cold nights.
What is the average precipitation and temperature for a tundra climate?
A tundra climate has average yearly rainfall of about 25cm and average temperatures below 4 degrees Celsius.
What is the average precipitation and temperature for a rain forest climate?
A rain forest climate has average yearly rainfall of about 200cm and a narrow range in temperatures that are always warm.
What is a Monsoon?
A monsoon is a seasonal change in the prevailing winds in the region of South and Southeast Asia, blowing from the southwest between May and September and bringing rain (the wet monsoon ), or from the northeast between October and April (the dry monsoon).
Higher elevations have _____ temperatures and lower elevations have _____ temperatures.
Higher elevations have LOW temperatures and lower elevations have HIGH temperatures.
How does latitude affect climate?
Latitude affects climate because the further away you get from the equator (more Northern or Southern latitude), the colder the climate on average. Higher latitudes receive less solar energy.
Name some natural causes of climate change.
1. Continental Drift - Change impact of ocean and atmosphere currents;
2. Volcanoes - Ash reflects sunlight back to space - leads to COOLING (reduced temperatures);
3. Sunspot Activity - 11 Year Sunspot Cycle; Low activity = colder temperatures.
What does Anthropogenic mean?
Anthropogenic means human caused.
What is the Greenhouse Effect?
The Greenhouse Effect is a natural phenomena where gases (molecules) in the Earth's atmosphere are warmed by the sun and retain that heat.
What does burning fossil fuels release?
Carbon Dioxide is released by the burning of fossil fuels.
Which two gases are most closely linked to global warming?
Carbon dioxide and methane are most closely linked to global warming.
Increased carbon dioxide leads to _____ average temperatures.
Increased carbon dioxide leads to INCREASED average temperatures.
Increasing the average temperatures on Earth can lead to ____
Increasing the average temperatures on Earth can lead to droughts with environments becoming more arid and subject to greater wind erosion.
Air flows from ___ pressure to ___ pressure.
Air flows from HIGH pressure to LOW pressure.
What is a thunderstorm?
A thunderstorm is when warm, humid air has been uplifted, becomes unstable, and falls as rain.
What three conditions are necessary for a Thunderstorm to occur?
Three conditions necessary for a Thunderstorm to occur:
1. Uplifting mechanism (low pressure area);
What is a tornado?
A Tornado is a violent rotating column of air extending from a thundercloud to the ground.
Why are tornados more common in the United States, especially in the middle of the country?
Warm, moist air from the Gulf of Mexico collides with cool, dry air from Canada.
What is a hurricane?
A hurricane is a high energy storm that forms over water that is at least 80 degrees Fahrenheit.
What causes the MOST deaths from a hurricane?
Storm surge causes the most deaths from a hurricane.
Name some manmade causes of climate change.
1. Increase in carbon dioxide due to the burning of fossil fuels;
2. Increase in methane due to agriculture and fossil fuel use;
3. Increase in nitrous oxide concentration due to agriculture.
What percentage of scientists agree that humans are involved in climate change?
97% of scientists agree that humans are involved in climate change. NONE are denying Global Climate Change. Only 3% (3 out of 100) Scientists disagree that humans are involved in climate change
Why are mining companies required to reclaim the area where they have mined?
Without reclamation, habitats are permanently destroyed and erosion increases.
What does renewable mean?
Renewable means that the resources is not depleted when used.
Name the renewable energy resources we learned.
Solar power, hydropower, wind power, biomass, geothermal power, water power (tides and waves) are the renewable resources we learned about.
What does nonrenewable mean?
Nonrenewable means that the resource cannot be replaced naturally at the same pace it is being used.
Name the nonrenewable energy resources we learned.
Coal, Petroleum, Natural Gas, and Nuclear Power are the nonrenewable energy resources we learned about.
Name the three fossil fuels.
Coal, Petroleum (crude oil), and natural gas.
Which fossil fuels burns the cleanest?
Natural gas burns the cleanest.
What is photochemical smog?
Photochemical smog is made from a reaction of nitrogen oxides and volatile organic compounds (VOCs) in the presence of ultraviolet radiation (sunlight) that occurs in the troposphere; Produced in series of chemical reactions and it is responsible for brownish haze in afternoons of sunny days.
What is acid rain?
There are higher than normal amounts of nitric and sulfuric acids in the atmosphere. These form wet deposition: acid rain, fog, and snow; Natural carbon dioxide in atmosphere is reason for rain's natural acidity of 5.6. Acid rain can have a pH as low as 4.3.
What is groundwater?
Groundwater is water that is stored beneath surface - more like water in a sponge than a "river".
What kind of consequences will an increase in population have on our drinking water supply?
1. It will increase demand for water;
2. It will increase pollution of the water;
3. It will increase the waste of the water.
What is groundwater depletion?
Groundwater depletion is long-term water-level declines caused by sustained pumping.
What is saltwater intrusion?
Saltwater intrusion occurs where water table near the coast drops. Saltwater is drawn toward the freshwater zones in the aquifer when too much freshwater is pumped out. Saltwater intrusion decreases freshwater storage in the aquifers.
What is water pollution?
Water pollution is the contamination of bodies of water. It can come from discharges of untreated sewage and industrial wastes.
Where do most of the pollutants in water come from?
Most of the pollutants in water come from activities of humans on land.
Why is polluted groundwater difficult to clean?
Polluted groundwater is difficult to clean because the recycling process of groundwater can take hundreds or thousands of years.
What chemical is used to disinfect water to kill bacteria?
Chlorine is the chemical is used to disinfect water to kill bacteria.
Wastewater Treatment plants use the same processes to clean water as what?
Wastewater Treatment plants use the same processes to clean water as natural aquatic systems only they do it faster.
Why do we treat water (effluent) before putting it back in the ocean or river?
Waste water is cleaned so it can be safe to return it to the environment.