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60 Cards in this Set

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  • Back
What kind of time is the geologic time scale measured in?
millions of years
How is the geologic time scale broken up into specific time chunks?
by eons, era, periods, and epochs based on evidence of rocks and/or fossils
How was the geologic time scale developed and why does it keep changing?
geologists are continuing to refine it by conducting fieldwork on rocks throughout the world
How and why does the law of superposition relate to the geologic time scale?
oldest is down first, just like the oldest is on the bottom of the time scale
What direction is the correct way to read the scale?
Oldest to youngest--bottom to top
What types of events typically define the breaks in the geologic time scale?
mass extinctions, developing events, natural disasters
What is MEE?
Mass Extinction Event
What is BY?
billions of years
What is MY?
millions of years
List the geologic time scale eons.
Precambrian, Phanerozoic
List the geologic time scale eras.
Paleozoic, Meszoic, Cenozoic
List the geologic time scale periods.
Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Tertiary, Quaternary
What eon makes up 88% of all time?
How old is the Earth?
4.6 billion years old
What is geology?
the study of earth and its life, especially recorded in rocks
The core makes up how much percent of the earth?
What is the inner core primarily made of?
iron and nickel
How hot is the inner core?
10,000+ degrees F
How deep inside the earth is the inner core?
3,200-3,960 miles below the earth's surface
Is the inner core a liquid, gas, or solid?
What is the outer core primarily made of?
iron, nickel, sulphur, oxygen
How hot is the outer core?
7200-9032 degrees F
How deep inside the earth is the outer core?
1800-3200 miles
Is the outer core a solid, liquid, or gas?
What is the Gutenberg Discontuity and where is it located?
It separates the core from the mantle and it is located between the mantle and the core.
The mantle makes up how much percent of the earth?
Where is the mantle located?
between the crust and core
How thick is the mantle?
1700 miles thick
Is the top of the mantle hotter or cooler than the base?
cooler-the closer to earth, the cooler it is
What geologic feature floats on the mantle?
What is the athenosphere?
it is the flowing part of the mantle that behaves like jello where convection takes place
What parts of the mantle make up the athenosphere?
the lower upper mantle
What is the lithosphere?
rigid part of the mantle
Where is the lithosphere located?
the upper upper mantle and crust
What is the Moho Discontinuity and where is it located?
it is the boundary between the crust and mantle and it is located between the two
How much percent of the earth does the crust take up?
The oceanic crust is how much percent of the earth's crust?
How thick is the oceanic crust?
8 miles thick
Is oceanic crust more or less dense than continental crust?
more dense
Is oceanic crust younger or older than continental crust?
The continental crust takes up how much percent of the earth's crust?
How thick is the continental crust?
100 miles
Is the continental crust more or less dense than the oceanic crust?
less dense--it floats on the mantle.
Define a rock.
a consolidated aggregate of mineral grains, particles of other rocks, or organic material
Define a mineral.
naturally occurring, inorganic solids that make up rocks
What is an igneous rock made from?
Where do igneous rocks form?
inside or outside the earth
What is an intrusive rock?
also known as a plutonic rock: it is formed inside the earth and crystallizes from cooling magma
What is magma?
molten rock beneath the earth's surface
What is an extrusive rock?
also known as a volcanic rock: it is formed outside the earth from cooling lava
How is a metamorphic rock formed?
from heat and pressure. it is either an altered or changed form of another rock, but does not melt
Where do metamorphic rocks form?
inside the earth
What distinguishing feature does a foliated metamorphic rock have?
What do non-foliated metamorphic rocks look like?
they don't have layers and are just a block
Where do sedimentary rocks form?
on top of the earth, sometimes buried a little
What is lithification?
hardening of rocks with the cementation after being buried
what is a detrital sedimentary rock?
it is composed of solid particles that were once part of other rocks
what is a chemical sedimentary rock?
it is derived from accumulation of biological or inorganic chemical precipitants
Who is James Hutton?
he discovered/invented the rock cycle
What is the basic theme of the rock cycle?
all rocks have been recycled throughout time and will continue doing so