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ANSWER SHEET A. Using the cross-section through Earth below, list the lettered r

ID: 115998 • Letter: A

Question

ANSWER SHEET A. Using the cross-section through Earth below, list the lettered rock units in order from oldest (bottom) to youngest (top). Start with the oldest. Youngest 1 Oldest-F- ROCK TYPES shale sandstone conglomerate diorite (gray outside contact indicates baked zone) basalt (orange outside contact indicates baked zone) granite siltstone The lawof_crosscutti- The Law ofCr after unit was deposited, but before unitwas deposited. rells you that Fault 1 moved What type of unconformity is between units E and R- Basalt V is younger than diorite D by the Law of The Law of and uf indicate that L is younger than D What type of unconformity is between units Mand inguley dis contor wmi What type of unconformity is between units L and B? DisconFermik ntar What type of unconformity is between units Wand R? Figure 5.6 Geologic History 55

Explanation / Answer

Considering the relative age, the rock units arranged from youngest to oldest are :

1.Layer W

2.Unconformity

3.Layer R

4.Layer V

5.Unconformity

6.Diorite D

7.Layer B

8.Layer S

9.Layer M

10. Unconformity

11.Fault

12.Tilting

13.Layer K

14.Layer E

15. Unconformity

16. Layer F

The law of cross-cutting tells yo that the Fault 1 moed after Unit K was deposited and before Unit M was deposited.

Unconformity between E and F - Disconformity (erosional plane parallel to the bedding planes of upper and lower surfaces).

Basalt V is younger than Diorite D by the relation of cross-cutting.

The law of Superposition and Cross cutting relationship indicate that L is younger than D.

Unconformity between K and M - Angular unconformity (contact that separates a younger, gentle dipping rock unit from the overlying rocks that are tilted)

Unconformity between L and B - Disconformity

Unconformity between W and R - Angular unconformity

B.

Trilobites - Cambrian(521 million yrs ago) till Upper Permian (252 million yrs ago)

Fish- Devonian (417 to 354 million yrs ago)