8: Measuring Geological Time (Exercises)
- Page ID
- 2047
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Q8.1 Cross-Cutting Relationships [SE]
Relative ages: 2: oldest: 3: middle, 1: youngest [SE]
Q8.2 Dating Rocks Using Index Fossils
Dating from overlapping fossils [SE]
Probable age: 92.6 to 92.7 Ma. If M. subhercynius was not present the interpreted age range would be 92.6 to 92.9 Ma
Q8.3 Isotopic Dating
Isotopic dating [SE]
With a ratio of 0.91 the age is 175 Ma (red dotted line)
Q8.4 Magnetic Dating
The possible age ranges are 3.05 to 3.12 Ma and 1.78 to2.00 Ma
Dating based on magnetic-reversal chronology [SE]
8.5 What Happened on Your Birthday?
Answers will vary.