GEO EXAM MEOW

On a topographic map, the closer the contour lines the ___ the slope

STEAPER

A scale of 1:1000 on a topo map indicates that 1 inch on the map represents how many length on the ground _______________ ? 

1000 inches

If the contour interval on a topo map is 10 meters, and one contour line is labeled 50 m the adjacent contour line would represent ?_  m in elevation 

60 or 40 (depding if we r going up or dowwn)

When you observe contour lines with hachures on a topographic map, this indicates that ___ ?

a depression in the land

an area where the elevation is going down

sink hole crater basin

How are streams indicated on a topographic map? ( HINT : The “V” rule )  

Contour lines form V-shapes that point upstream, indicating the direction the stream flow downhill.

On a topo map, how would you determine if a feature was a hill? 

Closed contour lines with elevation increasing toward the center. creating a circle

How would a depression or volcanic caldera be identified on a topo map?

closed contour lines with little tick marks (hachures) pointing toward the center.

The elevation between contour lines on a topo map is called the _____ ? 

contour interval

A set of circles inside circles (with hatchures) on a topo map indicate a ___________ ? 

a depression.

equation to calculate the gradient 

Gradient=Horizontal distance / Change in elevation

A contour interval is the  ____ ? 

how much higher or lower one line is from the next line on a map

What is the term that describes a specific location’s height above sea level?  

elevation

What does a contour represent on a map? 

line that connects points of the same elevation.

a volume of rock of a given type and age range

geologic unit 

size and shape of Earth’s surface features 

Topography 

line connecting points of equal elevation on a map  

contour lines

difference between the highest and lowest elevations  

relief

On a topographic map, contour lines that form a circle (without hachures) indicate a(n) ____

hill

What is relative dating?

Which things are older or younger without knowing exactly how old they are

What does the geologic time scale represent? 

shows the history of Earth divided into different time periods based on major events in the planet’s past.

What do scientists think the first life form was?

single-celled organism

What is a fossil? 

preserved remains or traces of a plant or animal

What parts of organisms are most likely to become fossilized?

• Bones

• Teeth

• Shells

Why do scientists study fossils? 

learn about the history of life on Earth.

Fossils can show how the earth's __________has changed over time.

environment

How can the relative age of fossils and rock layers be determined? 

• Lower layers are older.

• Higher layers are younger.

law of superpositon

undisturbed rock layers, the bottom layers are older and the top layers are younger

What is a natural fuel that was formed from the remains of once living organisms: 

fossil fuels

If a dike protrudes through several layers of rock, what can we conclude?

dike is younger than all the rock layers it cuts through.

dike

wall-like sheet of rock that forms when magma pushes up through cracks in existing rock layers and then hardens.

What is an unconformity? 

gap in the geologic record where rock layers are missing.

What is the meaning of 'law of superposition' in reference to a layered sequence of sedimentary rocks? 

bottom layers are the oldest

top layers are the youngest.

Each layer was deposited on top of the layer before it, like stacking books.

What is meant by the principal of original horizontality? 

sediment layers are originally deposited in flat, horizontal sheetsS

If theres a sandstone that is in contact with graphite, and contains fragments of graphite, what can you infer about which is older 

The graphite is older; the sandstone formed later and contains pieces of it.

unconformity.

gap in the rock record where older rock layers were eroded or removed before new layers were deposited on top.

What is an angular unconformity? 

older rock layers have been tilted or folded, then eroded, and later newer, flat layers of rock were deposited on top.

Which principle frequently uses dikes and faults for establishing sequences of events? 

Principle of Cross-Cutting Relationships.

Principle of Cross-Cutting Relationships.

that any feature (like a dike or fault) that cuts across other rock layers must be younger than the layers it cuts through.

What is the “Principle of Faunal Succession?” 

fossil organisms succeed one another in a definite and recognizable order through geologic time.

What is the Principle of Original Horizontality?  

sedimentary rock layers are originally deposited in flat, horizontal layers.

Which principle involves the use of fossils to correlate rocks?

Principle of Faunal Succession.

What does the term 'half-life' refer to? 

efers to the amount of time it takes for half of a radioactive substance to decay into a different, more stable material.

shear.

type of stress that causes rocks to slide past one another in opposite directions, kind of like rubbing your hands together side-by-side.

side-to-side motion

compression. 

type of stress that pushes rocks together.

This can cause folding or mountain building

tension. 

type of stress that pulls rocks apart.

It stretches the crust, making it thinner causes

• Cracks

• Normal faults

• Rift valleys

dip

The angle at which the rock layer tilts downward from the horizontal.

strike

The direction of the line formed where a rock layer intersects a horizontal surface (like the ground)

Does Folding occur when rocks behave A. as brittle solids or B. plastic fluids? 

B. plastic fluids

anticlines

• A fold that arches upward like an “A”

• Oldest rock layers are at the center

• Limbs slope away from the center

synclines 

• A fold that bends downward like a “U”

• Youngest rock layers are at the center

• Limbs slope toward the center

Folds whose limbs are horizontal are known as: 

recumbent folds.

dome. 

A dome is a type of upward, circular or elliptical fold in rock layers.

• The oldest rocks are at the center, and layers dip outward in all directions.

• It looks like an inverted bowl.

Basin  

A basin is a type of downward, circular or elliptical fold in rock layers.

• The youngest rocks are at the center, and layers dip inward from all directions.

• It looks like a bowl-shaped depression.

In a syncline, where are the youngest rock layer found? 

center of the fold.

In a plunging anticline, how does the fold axis plunge? 

into the ground at an angle instead of being horizontal.

Is a structural basin is a special case of: a syncline OR an anticline ? 

is a special case of a syncline.

A fault is observed where the hanging wall is displaced downward relative to the footwall. Is this is a normal fault or a reverse fault?  

normal fault.

The San Andreas Fault is an example of what type of fault? 

strike-slip fault.

Strike-slip faults can also be called ______ faults? 

transform faults.

Do Faults result from ductile deformation of rocks OR brittle deformation of rocks? 

brittle deformation of rocks.

  From what process do fractures result from?

brittle deformation

slow strain rates. 

gradual application of stress to rocks over a long period of time.

ductile deformation of rocks. 

occurs when rocks bend, stretch, or flow instead of breaking.

How do Transform faults occur (use a diagram) 

occur at plate boundaries where two tectonic plates slide past each other horizontally.

In a syncline to what direction do rock layers dip? (TOWARDS CENTER or AWAY FROM CENTER) 

 

dip towards the center of the fold.

At convergent plate boundaries where oceanic and continental crust meet what happens? 

denser oceanic crust is forced (subducted) beneath the lighter continental crust.melts the oceanic crust, forming magma, create volcanoes also causes earthquakes

Volcanic island arcs are associated with __________ plate boundaries 

convergent plate boundaries

Which of the mountains formed as a result of collision between two continents? 

 

fold mountains. Himalayas,

What increases with distance from a mid-ocean ridge? 

Age of the oceanic crust and thickness of the oceanic lithosphere

Partial melting and the production of magma takes place at ____?____ . plate boundary 

 

convergent plate boundaries.

The Hawaiian Islands formed at a _________ .  

hotspot.

The North American plate is bounded by _________ plate boundaries

all 3 

• Divergent boundary

• Convergent boundary

• Transform boundary

Which tectonic plate is being subducted beneath western South America? 

 

Nazca Plate

The formula to calculate total distance

Distance=Rate×Time

Volcanic island arcs are associated with _________ plate boundary 

 

convergent plate boundaries

What is the topographic feature at A called ? 

anticline

What is the name of the Mesozoic supercontinent that consisted of all of the present continents? 

Pangaea

When did the supercontinent Pangaea begin to break apart? 

early Mesozoic Era, around 200 million years ago

New oceanic lithosphere forms at __________ 

mid-ocean ridges

Approximately how many tectonic plates are there? (Major) 

7 major tectonic plates: African, Antarctic, Eurasian, Indo-Australian, North American, Pacific, and South American.

Approximately how many tectonic plates are there? ( Minor) 

(about 12–15 commonly recognized), such as the Nazca, Cocos, Caribbean, Philippine, Arabian, and Scotia Plates.