Isotope Geology and Geochronology

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I have an assignment on Isotope Geology and Geochronology that requires expertise in geology, chemistry, and Excel to complete. The questions are in the Excel document attached below. Could you please answer only questions 1 and 2? Also, provide all explanations and formulas used in a separate document. Please refrain from using any AI generations to complete the assignment.Thank you

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SWR 2A
SWR 2B
SWR 64B
SWR 18
SWR 9B
SWR 14B
SWR 17B
SWR 24
SWR 32 A
SWR 57
SWR 5b
SWR 80
176Hf/177Hf 87Sr/86Sr
143Nd/144Nd
0.282217
0.714511
0.511830
0.282531 0.71097813
0.512198
0.282835 0.77070293
0.512306
0.282277 0.70681884
0.511733
0.282552
0.710209
0.512213
0.282461
0.7134564
0.511848
0.282329 0.70456105
0.281935 0.80188666
0.511441
0.282430 0.71287381
0.511830
0.282525
0.7111574
0.512070
0.282671 0.71026969
0.512303
0.282537
0.710364
0.512215
GIVEN
CHUR 143/144
0.51263
CHUR 147/144
0.1962
Lambda Sm 147
6.54E-12
TIME
1.1E+08
CHUR 176/177
0.2828
CHUR 176Lu/177Hf
0.0332
Lambda 176Lu
1.87E-11
BE 87Sr/86 Sr
0.705
BE 87Rb/86Sr
0.09
Lambda 87Rb
1.42E-11
176Hf/177Hf in
granitoids from Swangkre- Rongmill traps in North India.
Calculate the initial Hf-Nd-Sr isotope composition, and epsil
Years. Concentrations are given to the right. Put your anser
Use the following:
isotope abundance of 85Rb = 0.2785, atomic weight of Rb =
isotope abundance of 86Sr = 0.9767 and atomic weight of S
isotope abundance of144Nd= 0.23798, atomic weight of Nd
isotope abundance of147Sm = 0.1499 and atomic weight of
isotope abundance of 176Lu= 0.02599, atomic weight of Lu
isotope abundance of 177Hf = 0.1860 and atomic weight of
87Sr/86Sr in 143Nd/144Nd in
EHf
ESr
ENd
l traps in North India.
e composition, and epsilon values of these samples, assuming an age of 110 Million
the right. Put your ansers on the specifiec columns
85, atomic weight of Rb = 85.468
7 and atomic weight of Sr = 87.0454
798, atomic weight of Nd = 144.24
99 and atomic weight of Sm = 150.36
599, atomic weight of Lu = 174.947
60 and atomic weight of Hf = 178.49
Elements ;>
Rb
Sr
123.4
22.98
450.0
3.0
13.3
56.8
1.1
239.6
12.3
20.8
36.7
9.7
Y
511.4
245.26
276.5
420.0
331.6
496.0
795.9
63.9
218.5
261.6
281.7
227.8
Zr
34.2
30.88
28.1
14.5
33.3
24.4
9.7
11.0
22.2
28.1
38.1
17.5
Nb
381.3
136.56
103.0
71.6
134.5
107.1
56.3
181.9
79.3
116.3
171.2
78.2
Cd
20.8
8.26
6.8
3.4
6.3
4.9
1.4
8.1
4.8
6.8
9.9
4.8
Sn
0.1
0.07
0.1
0.0
0.1
0.0
0.0
0.0
0.0
0.1
0.1
0.0
2.6
0.60
0.9
0.3
0.4
2.7
0.5
7.2
1.6
0.4
0.8
0.3
Cs
Ba
2.1
0.25
9.4
0.1
0.2
6.1
0.2
8.0
0.2
0.3
0.4
0.2
La
1,599.5
355.63
440.0
109.5
395.7
373.1
106.8
186.7
157.9
269.6
408.3
314.5
Ce
45.3
17.37
15.3
22.0
17.3
24.1
6.9
35.0
14.3
16.3
20.1
9.7
Pr
105.2
37.56
34.5
47.2
37.0
55.1
15.8
71.7
31.9
33.8
44.8
21.7
Nd
12.6
4.74
4.7
5.5
4.6
7.1
2.5
7.9
4.2
4.3
5.9
2.7
Sm
48.4
19.22
20.3
20.9
19.3
28.8
11.5
29.5
17.8
17.4
25.4
11.2
9.1
4.89
4.8
4.1
4.9
6.0
2.6
5.2
4.1
4.5
6.3
2.9
Eu
Gd
1.9
1.60
1.7
1.0
1.7
1.6
0.8
0.8
1.4
1.5
2.1
1.0
Tb
7.4
5.47
5.0
3.3
5.8
5.3
2.1
3.9
4.0
5.0
6.8
3.2
Dy
1.1
0.86
0.8
0.5
0.9
0.8
0.3
0.5
0.6
0.8
1.1
0.5
Ho
6.1
5.50
5.0
2.6
5.8
4.3
1.6
2.4
3.9
5.1
6.7
3.3
Er
1.2
1.11
1.0
0.5
1.2
0.9
0.3
0.4
0.8
1.0
1.3
0.7
Tm
3.3
3.12
2.8
1.4
3.3
2.4
0.9
1.0
2.3
2.8
3.8
1.8
0.5
0.43
0.4
0.2
0.4
0.4
0.1
0.1
0.3
0.4
0.5
0.3
Yb
Lu
2.9
2.69
2.5
1.4
2.8
2.4
1.0
1.0
2.1
2.4
3.3
1.5
Hf
0.4
0.39
0.4
0.2
0.4
0.4
0.2
0.2
0.3
0.3
0.5
0.2
Ta
9.2
3.46
2.6
1.9
3.4
2.7
1.6
4.8
2.0
3.0
4.3
2.0
Pb
1.6
0.82
0.5
0.7
0.4
1.0
2.8
1.1
1.0
0.5
0.8
0.7
Th
33.8
7.38
26.7
13.2
6.4
27.0
5.4
12.6
5.0
8.1
6.8
4.0
U
24.7
3.14
1.6
9.9
3.0
5.3
3.7
14.2
2.1
3.4
1.5
1.7
2.7
0.31
0.3
1.9
0.4
1.5
1.9
0.9
0.6
0.3
0.3
0.2
Li
Sc
28.8
7.22
28.8
5.0
9.7
12.0
0.7
31.0
7.0
4.7
11.1
3.1
Ti
21.4
18.76
23.9
12.5
19.6
22.8
3.9
10.7
38.3
18.9
22.9
11.7
V
7,377.0
7,216.78
10,837.0
1,123.7
6,512.7
4,577.3
1,019.9
1,511.7
8,297.1
6,602.3
10,167.0
4,377.2
Cr
140.6
138.03
259.5
26.2
131.4
133.3
83.3
18.9
50.7
123.9
121.6
86.6
Co
325.7
31.91
37.9
10.3
40.1
7.8
7.2
9.2
1.2
54.2
28.3
24.1
Ni
71.8
54.37
61.8
142.3
61.7
70.5
231.4
75.7
98.2
55.1
54.0
46.2
173.9
11.69
81.5
7.0
13.6
7.0
3.6
4.2
1.2
11.8
15.1
7.7
Cu
Zn
40.2
8.37
0.2
0.5
9.3
2.5
0.1
7.0
5.4
9.8
11.3
5.7
Ga
95.3
111.14
150.1
50.5
117.6
64.6
9.2
44.7
113.0
104.8
127.1
69.0
18.4
19.95
19.1
13.7
21.4
18.3
19.1
13.2
17.9
20.6
22.3
12.9
143Nd/144Nd
176Hf/177Hf Lu/Hf
kaps36-cpx
0.513064
Pa27-cpx
0.513180
0.283319
SLC326-4
0.513066
0.28463
slc328
0.513036
0.283207
0.513035
0.283472
0.513034
0.283329
slc341-cpx
slc466-cpx *Os from Neptune
0.283116
Sm/Nd
0.3167
0.3060
0.3116
0.4379
0.5587
0.2871
0.0812
0.3139
0.2055
0.2630
0.1617
0.2465
0.3340
0.2212
0.1039
0.2780
0.4866
0.2576
0.2283
0.2437
slc470cpx
0.513019
0.284409
SLC 319
SLC 320
SLC 405
0.513049
0.513051
0.513045
0.283326
0.286009
0.283528
420 cpx
0.512985
0.28353
0.1432
0.2091
402 cpx
0.513082
0.283584
0.1826
0.2598
115048-2
0.513009
0.284049
0.3176
0.2661
115048-1
0.51303
0.283497
0.1874
0.2683
114989-37
0.513035
0.283198
0.0478
0.2467
114989-3
114745-2
114745-3
0.513077
0.283504
0.283207
0.28296
0.3097
0.2897
0.2882
0.2953
0.513090
0.513085
The present day depleted mantle
176Hf/177Hf = 0.2832
143Nd/144Nd= 0.5132.
GIVEN
CHUR 143Nd/144Nd t
0.512638
CHUR 147Sm/144Nd
0.1962
Lambda Sm 147
CHUR 143Nd/144Nd 3Ga
6.54E-12
0.50875054
DM 143Nd/144Nd t
0.5132
DM 147Sm/144Nd
DM 143Nd/144Nd o
0.22456416
0.50875054
CHUR 176/177
0.2828
CHUR 176Lu/177Hf
0.0332
Lambda 176Lu
1.87E-11
0.1224
0.0720
Sm-Nd and Lu-Hf isotope systematics of peridotites fr
A) Calculate the Sm/Nd and Lu/Hf model ages assumi
B) Calculate the Sm/Nd and Lu/Hf model ages assumi
from Chondritic Earth 3Ga ago.
C) What do you make of the Sm
D). For the graduate students: Are these rocks meta
happened (i.e. recently or a long time ago (i.e. 100 m
depleted upper mantle (Plot present day Nd isotope
CHUR like isotope evolution plot of ratio vs. time. Tha
Put your asnwers in the designated columns
Note: You can use the parameters from Question 1 if
CHUR 176Hf/177Hf 3Ga
?
DM 167Hf/177 Hf today
DM 176Lu/177Hf
DM 167Hf/177 Hf @3Ga
0.2832
?
?
176Lu/177Hf147Sm/144Nd
ENd CHUR model ageEHf CHUR model age
Hf isotope systematics of peridotites from Hawaii (Bizimis et al, 2007).
e Sm/Nd and Lu/Hf model ages assuming derivation from Chondritic earth,
Sm/Nd and Lu/Hf model ages assuming derivation from a Depleted mantle, which originated
3Ga ago.
make of the Sm-Nd and Lu-Hf ages? what do you make of negative ages?.
duate students: Are these rocks metasomatized or disturbed? Can you tell when this
recently or a long time ago (i.e. 100 million years or later). Can they be pieces of the
(Plot present day Nd isotope ratio and the initial isotope ratio at the model age,on a
pe evolution plot of ratio vs. time. That’s your clue ).
ers in the designated columns
use the parameters from Question 1 if you need to.
ENd DM model ageEHf DM model
Table 1. Sr-Nd-Hf-Os isotope compositions of the Oahu peridotites
187
Os/188Os (bulk
rock)
Os conc. (ppb)
Re conc. (ppb)
SLC vent
SLC 470 a
0.1168
SLC 319 a
SLC 320
0.1185
a
nd
SLC 405 a
0.1237
115048-2
0.1187
3.05
114989-2
0.1176
1.98
115048-1
0.1189
2.98
115048-26
0.1138
2.56
114989-4
0.1163
2.98
0.35
114989-38
0.1206
2.94
0.56
114989-37
0.1291
8.17
0.16
115048-5
0.1225
2.56
115048-3
0.1227
2.76
0.14
115048-4
0.1231
2.86
0.09
115048-25
0.1244
2.94
114989-3
0.1251
2.6
114989-36
0.1195
1.8
114745-2
b
0.1258
114745-3
b
0.1297
Pali-Kaau
vent
114744-1 b
0.126
114744-2B
b
0.1269
114908-20
b
0.1238
114908-22
b
0.1259
KAPS36
Pa27
a
a
0.13
0.65
0.2
0.124
0.1262
114908-7
0.1252
114908-21
0.1248
1.13
0.16
114908-1
0.1213
1.25
0.1
114908-2
0.1215
1.05
0.19
114908-3
0.1251
1.66
0.13
114908-5
0.1216
1.47
0.21
114886-3
0.1218
2.61
0.12
114886-4
0.1218
2.15
0.19
T RD (Ma)
T depletion
Os isotopes for peridotites from
a) Calculate the Re
lecture notes). Remember: TRD
B) calculate the MODEL age of
course). Remember, this is the
and evolved to present day va
C) compare these ages, where
ages and why).
isotopes for peridotites from Oahu, Hawaii (Bizimis et al., 2007).
a) Calculate the Re-depletion age (TRD) of these peridotites (all necessarry parameters are given in
lecture notes). Remember: TRD assumes that Re/Os = 0 for these rocks.
B) calculate the MODEL age of these rocks (for those sample with both Re and Os concentrations, of
course). Remember, this is the age where the rock “separated” from the Bulk Earth evolution line,
and evolved to present day value with the specific Re/Os ratio.
C) compare these ages, where possible, and discuss your results (similarities , differences between
ages and why).

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