Map and Cross Section Interpretation

Question 1

Angular Unconformity

Answer 1

Unconformity between tow rocks dipping at different angles, older rocks below are often dipping more steeply than rocks above.

Question 2

Disconformity

Answer 2

type of paraconformity with rocks above and below parallel, but the unconformity surface is not parallel to bedding

Question 3

Eon

Answer 3

Four subdivision of time: Three eons- Hadea, Archean, and Proterozoic- cover almost half of time on earth. Fourth Eon- Phanerozoic- incorporates Paleozoi, Mesozoic, and Cenozoic eras.

Question 4

Epoch

Answer 4

Subdivision of Tertiary and Quaternary periods

Question 5

Era

Answer 5

Subdivisions of Phanaerozoi: Paleozoic, Mesozoic, and Cenozoic

Question 6

Ga

Answer 6

abbreviation of Giga-annum; one billion years

Question 7

Ka

Answer 7

abbreviation of Kilo-annum; one thousand years

Question 8

Key Beds

Answer 8

Well defined, easily identified strate that is distinctive enough to be useful in correlation mapping

Question 9

Ma

Answer 9

Mega annuam- one million years

Question 10

Non conformity

Answer 10

unconformity formed by older igneous rocks in contact with younger sediments, indicating a missing time after the ingneous intrusion

Question 11

Paraconformity

Answer 11

unconformity in which beds are parallel above and below the break.

Question 12

Period

Answer 12

Subdivision of the three eras; Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian in the Paleozoic, Triassic, Jurassic, and Cretaceous in the Mesozoic, and Tertiary and Quaternary in the Cenozoic.

Question 13

Rule of V’s

Answer 13

Outcrop pattern of a formation or fault as it crosses valley forms a V in map view, The V points in direction that the formation underlies the Valley.

Question 14

Township and Range

Answer 14

a 6 by 6 mile square, divided into 36 sections. Townships measured in rows N and S of Baseline, Ranges are measured columns East and West of Principal meridian.