McKenzie Mikesell
Geology 102
Geological Time

17.1
A) The oldest rocks are at the bottom of the bunch. (Dirty Laundry effect).
B) It would be the same because they build up over time and the layers at the bottom are older.

17.2
A) The incline beds in figure 17.2 are younger.
B) Because the beds on top are older than the beds on the bottom and have not flipped over.

C) Younger
D) Younger
E) Younger, You cannot deform a structure that is not there yet.
F) Lava flow has smaller mineral crystals- extrusive
Sill Display-Intrusive- Display larger crystals.

17.3
A) Xenolith is a clast of preexisting rock contained within an igneous rock.
B) Its older, clasts are usually older than the rock in which it is included. 17.4
DIAGRAM
A) Drawing
B) Right side up because ripple marks point up towards the younger material
D) 4 is the youngest

17.5 17.9
C – G – A – I – K – F – D – J – H – B
Layers E, A, F and I were once horizontal layers that were deformed with tilt. 17.10.
E – A – F – I – C – K – G – D – H – J formed sequentially then underwent angular conformity and experienced some erosion.
17.11.
A – F – B – E – H – K – J – I – D – G – C

17.12
D – J – F – G – C – B – E – I – H – A

17.6
A) Chonetes ,cleiothyridina, neospirifer, petrocrania, schizophoria

2)Leptanea Atrypa, chonetes, petrocrania, platystrophia, schizophoria

3)Petroerania platystrophia, strophomena

B1)youngest
B2) significant gap that spans the Devonian and Mississippian periods, about 98 million years.
C1)The tilt occurred earlier because Mississippian period because I compared the geological records to the chart in 17.10
C2) The neospirifer fossils
C3) Triassic period

17.7
A) yes, they were the same in both place until they began to change in year 5 and were no continuous. Year E.
B) Western has 2 similar deposits as Eastern. As eastern continues the same deposits as eastern continues the same deposit westerns skips. Then it repeats until year 8.

17.8
A1) 713 million years old
A2) 48.8 million years old
A3) 5,730 years
A4) 1.3 billion years old

B
I)E ~ 89.1 million years old; A ~ 0.28 billion years old (280 million)
; F ~ 0.33 billion years old (330 million)

II) F is younger than the preexisting layers, and is 330 million years old.
III)folded after the formation of J
IV) The unconformity between layer I and the preexisting layers appears to be well eroded.
V) 200-250 million years old