Test 2 Terms

Question 1

Absolute dates

Answer 1

exact date of rocks, can be done by isotopic dating

Question 2

Angular unconformity

Answer 2

Folded sedimentary rocks that are overlain by younger, more flat-lying strata
during deposition, folding and tilting occurred

Question 3

Correlation

Answer 3

process of establishing the equivalence of rocks of similar age in different areas

Question 4

Disconformity

Answer 4

gap in the rock record represents a period where erosion rather than deposition occurred

Question 5

Fossil

Answer 5

remains or traces of organisms preserved from the geologic past

Question 6

Half-life

Answer 6

The time required for one-half of the atoms of a radioactive substance to decay

Question 7

Index fossil

Answer 7

a fossil that is associated with a particular span of geologic time

Question 8

Isotope

Answer 8

Variaties of the same element that have different mass numbers: their nuclei contain the same number of protons but different numbers of neutrons

Question 9

Nonconformity

Answer 9

younger sedimentary strata overlie older metamorphic or intrusive igneous rocks

Question 10

Paleontology

Answer 10

study of fossils

Question 11

Principle of Cross-Cutting Relationships

Answer 11

geologic features cut across rocks must form after the rocks they cut through

Question 12

Principle of Fossil Succession

Answer 12

A principle by which fossil organisms succeed one another in a definite and determinable order, and any time period can be recognized by its fossil content

Question 13

Principle of inclusions

Answer 13

fragments of one rock unit that have been enclosed within another

Question 14

Principle of lateral continuity

Answer 14

sedimentary beds originate as continuous layers that extend in all directions until they eventually grade into a different type of sediment or until they thin out at the edge

Question 15

Principle of superposition

Answer 15

most basic principle of relative dating: that in an under formed sequence of sedimentary rocks, each bed is older than the one above and younger than the one below

Question 16

Radiometric dating

Answer 16

the procedure of calculating the absolute ages of rocks and minerals that contain certain radioactive isotopes

Question 17

relative dates

Answer 17

determining the chronological order or events by placing rocks and structures in their proper sequence or order

Question 18

types of fossilization

Answer 18

Permineralization, molds and casts, carbonization and impressions, amber

Question 19

Unconformity

Answer 19

a surface that represents a break in the rock record, caused by erosion and nondeposition

Question 20

Basin

Answer 20

circular down folded structure

Question 21

Brittle

Answer 21

Breaks

Question 22

Compression

Answer 22

Differential stress that shortens a rock body

Question 23

Deformation

Answer 23

General term for the processes of folding, faulting, shearing, compression, or extension of rocks as the result of various natural forces

Question 24

Dome

Answer 24

roughly circular upfolded structure

Question 25

Ductile

Answer 25

type of solid-state flow that produces a change in the size and shape of a rock body without fracturing. Occurs at depths where temperatures and confining pressures are high

Question 26

Elastic

Answer 26

sudden release of stored strain in rocks that result in movement along a fault

Question 27

Fault

Answer 27

break in the rock mass along which movement has occurred

Question 28

Fold

Answer 28

A bent layer or series of layers that were originally horizontal and subsequenetly deformed

Question 29

Shear

Answer 29

Stress that causes two adjacent parts of a body to slide past one another

Question 30

Stress

Answer 30

The force per unit area acting on any surface within a solid

Question 31

Tension

Answer 31

The type of stress that tends to pull a body apart

Question 32

Types of Faults

Answer 32

dip-slip strike-slip Oblique-slip

Question 33

Types of folds

Answer 33

Anticlines and synclines Monoclines Domes and Basins

Question 34

Earthquake

Answer 34

Vibration of Earth Produced by the rapid release of energy

Question 35

Epicenter

Answer 35

The location on Earth's surface that lies directly above the focus of an earthquake

Question 36

Hypocenter

Answer 36

focus of an earthquake

Question 37

Lithification

Answer 37

the process, generally involving cementation or compaction of converting sediments to solid rock

Question 38

Magnitude

Answer 38

an estimate of the total amount of energy released during an earth-quake, based on seismic records

Question 39

reflection

Answer 39

the redirection of some waves back to the surface when seismic waves hit a boundary between different Earth materials

Question 40

seismic waves

Answer 40

rapidly moving ocean wave generated by earthquake activity that is capable of inflicting heavy damage in coastal regions

Question 41

Asthenosphere

Answer 41

A subdivision of the mantle situated below the lithosphere | zone of weak material below 100 kilometers

Question 42

Conduction

Answer 42

The transfer of heat through matter by molecular activity

Question 43

Convection

Answer 43

The transfer of heat by the mass movement or circulation of a substance