Module 2

Question 1

**relative dating

Answer 1

Dating methods that arrange material evidence in a linear sequence, each object in the sequence being identified as older or younger than another object.

Question 2

**absolute/numerical dating

Answer 2

Dating methods based on laboratory techniques that assign age in years to material evidence.

Question 3

stratum

Answer 3

Layer; in geological terms, a layer of rock and soil.

Question 4

law of (stratographic) superposition

Answer 4

A principle of geological interpretation stating that layers lower down in a sequence of strata must be older than the layers above them and, therefore, that objects embedded in lower layers must be older than objects embedded in upper layers.

Question 5

law of crosscutting relationships

Answer 5

A principle of geological interpretation stating that where old rocks are crosscut by other geological features, the intruding features must be younger than the layers of rock they cut across.

Question 6

biostratigraphic dating

Answer 6

A relative dating method that relies on patterns of fossil distribution in different rock layers.

Question 7

seriation

Answer 7

A relative dating method based on the assumption that artifacts that look alike must have been made at the same time.

Question 8

**assemblage

Answer 8

Artifacts and structures from a particular time and place in an archaeological site.

Question 9

**isotopic dating

Answer 9

Dating methods based on scientific knowledge about the rate at which various radioactive isotopes of naturally occurring elements transform themselves into other elements by losing subatomic particles.

Question 10

**nonisotopic dating

Answer 10

Dating methods that assign age in years to material evidence but not by using rates of nuclear decay.

Question 11

**dendrochronology

Answer 11

Dendrochronology yields numerical dates for trees and objects made of wood. Crosscut section of a mature tree exposes a series of concentric rings, which normally accumulate annually over the tree’s life.

Question 12

**Radiocarbon dating

Answer 12

Absolute dating method
once something dies, stops taking in nonradioactive carbon, and the radioactive carbon decays at a known rate, so can use this to determine how old yo

Question 13

**Potassium_Argon Dating

Answer 13

Can use to tell when molten lava cools and crystallizes, as potassium 40 stays and then decays into argon.

Question 14

**Typology

Answer 14

Classifying fossils or artifacts into a series of types on the basis of their similarities and differences

Question 15

Fission Track Dating

Answer 15

Based on decay of radioactive material in rock, looks at tracks of uranium 238 as it splits in rock, atoms leave tracks. More time passes, more splits happen.

Question 16

Uranium-Series Dating

Answer 16

Uses Uranium and Thorium to date soil deposits that formed in ancient lake or sea beds.

Question 17

Electronic Spin Resonance (ESR) Dating

Answer 17

Based on fact that tooth enamel in a living organism is free of uranium but begins to absorb uranium after burial. Detects rate at which uranium accumulated in tooth after burial.

Question 18

Molecular clock

Answer 18

Based on assumption that genetic mutations accumulate in DNA at a constant rate, most accurately measured in mtDNA (mitochondrial DNA). Deduces time between species since they shared a common ancestor.

Question 19

Ocean and Ice Cores

Answer 19

Source of information on past climates. Ocean waters and dead Foraminefera (they sink down to bottom of ocean floor when dead) contain O16 and O18. Bla bla bla.