Earth History 8E21 - Fossils & Geologic Time

Question 1

remains or traces of animals, plants and other organisms from the past; usually at least 10000 years old

Answer 1

Fossils

Question 2

fossil known to have lived in a particular geologic age that can be used to determine the date of the rock layer in which it was found

Answer 2

Index Fossil

Question 3

a fossil that must be studied microscopically

Answer 3

microfossil

Question 4

forms when sediments bury an organism and the sediments change into rock; the organism decays leaving a cavity in the shape of the organism

Answer 4

mold fossil

Question 5

forms when the mud or sand hardens to stone where a footprint, trail, or burrow of an organism was left behind

Answer 5

trace fossil

Question 6

forms when entire organisms or parts of organisms are prevented from decaying by being trapped in rock, ice, tar, or amber

Answer 6

preserved fossil

Question 7

forms when organisms or parts, like leaves, stems, flowers, fish, are pressed between layers of soft mud or clay that hardens squeezing almost all the decaying organism away leaving the carbon imprint in the rock

Answer 7

carbonized fossil

Question 8

forms when a mold is filled with sand or mud that hardens into the shape of the organism

Answer 8

cast fossil

Question 9

forms when minerals soak into the buried remains, replacing the remains, and changing them into rock

Answer 9

petrified fossil (permineralized fossil)

Question 10

measurement of the known rates of decay of radioactive materials that an object contains in order to determine the age of the object

Answer 10

Absolute (radioactive)Dating

Question 11

states that in undisturbed rock layers that newer layer will be deposited over older layers

Answer 11

Law of Superposition

Question 12

states rock layers that cut across other rock layers are younger than those they cut

Answer 12

Law of Crosscutting Relationships

Question 13

determining the age or order of things from the past or past events without knowing or calculating the actual age

Answer 13

Relative Age Dating

Question 14

rock formed by deposition of sand, clay and other pieces of rock that are compacted together under pressure

Answer 14

Sedimentary rock

Question 15

radioactive heavy metal that is an abundant source of nuclear energy (14 known isotopes, used in radioactive dating)

Answer 15

uranium

Question 16

fracture along which blocks of the Earth’s crust that can be caused by the shifting or dislodging of the Earth’s crust. Types include normal, strike slip, or reverse

Answer 16

Fault

Question 17

system of chronological measurement that relate to the history of events in Earth’s past, consisting of fossils and major events

Answer 17

Geologic Time Scale

Question 18

a core sample of ice removed from a sheet of ice. Properties of the ice and the crystallized components in the ice are used to reconstruct climatic record

Answer 18

Ice Core

Question 19

type of rock formed under or above ground when magma or lava cools

Answer 19

Igneous rocks

Question 20

rock created from the transformation of other types of rock through heat and pressure

Answer 20

Metamorphic rock

Question 21

the crust that makes up the continents

Answer 21

Continental Plate

Question 22

the change in a geographic area caused by earthquakes, volcanoes, mountains forming, and other natural phenomena.

Answer 22

Geographic Change

Question 23

the study of the rocks, processes, and history of Earth

Answer 23

Geology

Question 24

the part of Earth’s crust that underlies the oceans

Answer 24

Oceanic Plate

Question 25

the movement or study of the movement of Earth's crust (the movement of the tectonic plates is responsible for geologic and subsequent biologic change over time)

Answer 25

Plate Tectonics

Question 26

more dense tectonic plate dives under another, forms trench, causes volcanos, and earthquakes (Andes Mountains)

Answer 26

convergent plate boundary

Question 27

process in which sediment is laid down in new locations (via glaciers, water, wind, gravity)

Answer 27

deposition

Question 28

two plates moving away from each other, separating, spreading apart

Answer 28

divergent plate boundary

Question 29

the process of wearing or grinding something down

Answer 29

erosion

Question 30

the end of the last type of a specific individual or a group of species (the capability to reproduce and survive is lost)

Answer 30

extinction

Question 31

when the land is forced together at a convergent plate boundary

Answer 31

folding

Question 32

when two oceanic plates pull apart, magma rises and new crust is formed

Answer 32

sea-floor spreading

Question 33

material deposited by water, wind, or glaciers

Answer 33

sediment

Question 34

molten (liquid) rock that reaches the Earth's surface

Answer 34

lava

Question 35

a strike-slip fault that occurs typically between segments of a mid-ocean ridge or other tectonic-plate boundary and that is characterized by shallow high-magnitude earthquakes

Answer 35

transform fault

Question 36

serve as excellent index fossils, enabling geologists to date the age of the rocks in which they are found, and possibly the second-most famous fossil group after the dinosaurs

Answer 36

trilobites

Question 37

Earth's crust and rigid part of the upper mantle

Answer 37

lithosphere

Question 38

molten (liquid) rock beneath the Earth's surface

Answer 38

magma

Question 39

a divergent boundary in the ocean where new sea floor is being made

Answer 39

mid-ocean ridge

Question 40

a hypothetical continent including all the landmass of the earth

Answer 40

Pangaea

Question 41

a process that explains the basic relationships among igneous, metamorphic, and sedimentary rocks

Answer 41

rock cycle

Question 42

a fissure in the earth's crust through which gases erupt

Answer 42

volcano

Question 43

disintegration or alteration of rock in its natural or original position at or near the Earth’s surface through physical, chemical, and biological processes induced or modified by wind, water, and climate

Answer 43

weathering

Question 44

the layer of the Earth below the crust and above the core

Answer 44

mantle

Question 45

a bowl-shaped geological formation at the top of a volcano

Answer 45

crater

Question 46

a large crater caused by the violent explosion of a volcano

Answer 46

caldera

Question 47

a rocky object that orbits the sun and has an average size between a meteoroid and a planet

Answer 47

asteroid

Question 48

a stratum (layer) of rock (especially sedimentary rock)

Answer 48

bed (in geology)

Question 49

the theory that the universe originated sometime between 10 billion and 20 billion years ago from the cataclysmic explosion of a small volume of matter at extremely high density and temperature

Answer 49

Big Bang Theory

Question 50

a ravine formed by a river in an area with little rainfall

Answer 50

canyon

Question 51

a shift in the world's average weather and temperature

Answer 51

climate change

Question 52

one of the large landmasses of the earth

Answer 52

continent

Question 53

the gradual movement of very large land masses

Answer 53

continental drift

Question 54

the outer layer of the Earth

Answer 54

crust

Question 55

the organic phenomenon of rotting

Answer 55

decay

Question 56

vibration from underground movement along a fault plane

Answer 56

earthquake

Question 57

the longest unit of geological time

Answer 57

eon

Question 58

a unit of geological time that is divided into ages

Answer 58

epoch

Question 59

a major division of geological time

Answer 59

era

Question 60

the sudden occurrence of a violent discharge

Answer 60

eruption

Question 61

sequence of events involved in the development of a species

Answer 61

evolution

Question 62

the state of being no longer in existence

Answer 62

extinction

Question 63

the time required for something to fall to half its initial value (in particular, the time for half the atoms in a radioactive substance to disintegrate)

Answer 63

half-life

Question 64

a stony or metallic object from space that hits the earth

Answer 64

meteorite

Question 65

a series of hills or mountains

Answer 65

mountain chain

Question 66

the earth science that studies fossil organisms

Answer 66

paleontology

Question 67

a unit of geological time when a system of rocks formed

Answer 67

period

Question 68

the process of turning some plant material into stone

Answer 68

petrifaction

Question 69

a rigid layer of the Earth's crust

Answer 69

plate

Question 70

belonging to or existing before recorded times

Answer 70

prehistoric

Question 71

a long narrow natural elevation or striation

Answer 71

ridge