Samples 87-Rb/86-Sr 87-Sr/86-Sr 1a 763 17.337 1b 41.52 1.7337 2 107.12 3.093 3 1
ID: 915270 • Letter: S
Question
Samples
87-Rb/86-Sr
87-Sr/86-Sr
1a
763
17.337
1b
41.52
1.7337
2
107.12
3.093
3
166.7
4.543
4
138.7
3.858
5
330.7
8.057
6
82.7
2.741
Isotopic Geochronometers: Use the slope to calculate a date for these samples. The question asks “Calculate the slope and intercept of a Rb-Sr isochron by the method of least squares using data for micas from the Amitsoq gneiss”.
Use the equation: ( (lambda) = 1.42x10^-11 a-1)
The answer to the problem is:
intercept = 0.8806
slope = 0.02159
t = 1504x106 a
Please show the steps on how to get this answer.
Samples
87-Rb/86-Sr
87-Sr/86-Sr
1a
763
17.337
1b
41.52
1.7337
2
107.12
3.093
3
166.7
4.543
4
138.7
3.858
5
330.7
8.057
6
82.7
2.741
Explanation / Answer
Plot 87-Rb/86-Sr on X axis and 87-Sr/86-Sr on Y axis. We obtain a straight line with slope 0.0216 and intercept 0.8791 , which are close to the values given in the qesution.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.