<p>The approach adopted by <a href="https://en.wikipedia.org/wiki/Charles_Lyell" rel="nofollow noreferrer">Charles Lyell</a> (and other writers in a similar timeframe), in his book <a href="https://archive.org/details/principlesgeolo05lyelgoog/page/n3/mode/2up" rel="nofollow noreferrer">'Principles of Geology'</a> which was first published in the 1830s was to look at processes in the modern landscape where the rate of change could be determined by observation or from historical evidence, and assuming that similar processes operated at similar rates in the geological past. So, for instance, if you measure the amount of sediment transported by a river today, and you measure the volume of sediment in that river's delta, you can estimate how long that delta took to form. If you see a similar delta  in the geological record, you can assume it took a similar time to form. Lyell's estimates of the age of the earth were low, but as the concept of plate tectonics, with it's progressive recycling of rocks through subduction wasn't recognised, it was remarkably prescient.</p>

CC BY-SA 4.0
2021-08-05T11:22:17.260Z
2021-08-05T21:46:23.563Z
2021-08-05T21:46:23.563Z
Andy M
<p>Did geologists determine the age of rocks and fossils before the advent of modern scientific dating methods such as <a href="https://www.nature.com/scitable/knowledge/library/dating-rocks-and-fossils-using-geologic-methods-107924044/" rel="nofollow noreferrer">radiometric, electron spin resonance and thermoluminescence</a>?</p>
<p>If they did, does anyone know how they went about it?</p>

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2021-07-30T16:51:41.377Z
There was not an absolute method before radiometric dating, as far as I know.  They used relative methods, but physicists had estimated the age of the Earth to be much less than the current accepted value... so the estimated ages were not good.  https://en.wikipedia.org/wiki/Age_of_Earth#Early_calculations
f.thorpe
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2021-07-31T15:19:10.373Z
very relevant link https://en.wikipedia.org/wiki/Relative_dating
John
CC BY-SA 4.0
2021-08-01T11:42:41.303Z
What time frame do you consider to be "modern"? I would consider "modern" to mean techniques developed in the last 100 years or so. If that's the case, every currently used dating technique is "modern".
David Hammen
CC BY-SA 4.0
2021-08-01T14:50:13.917Z
@David Hammen Radiometric dating started in 1905 so anything before that. 
 https://en.m.wikipedia.org/wiki/Radiometric_dating
Rick
CC BY-SA 4.0
2023-08-15T19:00:25.987Z
Dendrochronology was invented in the late 1800's. And can be used to give absolute dates for recent geologic time frames. keep in mind geology as a science is very young and basically started in the late 1700's.
John
<geology><paleontology><dating><history-of-science>
Did geologists determine the age of rocks and fossils before the advent of modern scientific dating methods?
Rick
# Did geologists determine the age of rocks and fossils before the advent of modern scientific dating methods?

(Asked by: username_0 on 2021-07-30)

Did geologists determine the age of rocks and fossils before the advent of modern scientific dating methods such as [radiometric, electron spin resonance and thermoluminescence](https://www.nature.com/scitable/knowledge/library/dating-rocks-and-fossils-using-geologic-methods-107924044/)?

If they did, does anyone know how they went about it?

**Tags:** geology, paleontology, dating, history-of-science

> **Comments:**
> **username_1**: There was not an absolute method before radiometric dating, as far as I know.  They used relative methods, but physicists had estimated the age of the Earth to be much less than the current accepted value... so the estimated ages were not good.  https://en.wikipedia.org/wiki/Age_of_Earth#Early_calculations  
> **username_2**: very relevant link https://en.wikipedia.org/wiki/Relative_dating  
> **username_3**: What time frame do you consider to be "modern"? I would consider "modern" to mean techniques developed in the last 100 years or so. If that's the case, every currently used dating technique is "modern".  
> **username_0**: @username_3 Radiometric dating started in 1905 so anything before that.   https://en.m.wikipedia.org/wiki/Radiometric_dating  
> **username_2**: Dendrochronology was invented in the late 1800's. And can be used to give absolute dates for recent geologic time frames. keep in mind geology as a science is very young and basically started in the late 1700's.  

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## 1 answers

### Answer by username_4 on 2021-08-05. Score: 6 | Accepted answer

The approach adopted by [Charles Lyell](https://en.wikipedia.org/wiki/Charles_Lyell) (and other writers in a similar timeframe), in his book ['Principles of Geology'](https://archive.org/details/principlesgeolo05lyelgoog/page/n3/mode/2up) which was first published in the 1830s was to look at processes in the modern landscape where the rate of change could be determined by observation or from historical evidence, and assuming that similar processes operated at similar rates in the geological past. So, for instance, if you measure the amount of sediment transported by a river today, and you measure the volume of sediment in that river's delta, you can estimate how long that delta took to form. If you see a similar delta in the geological record, you can assume it took a similar time to form. Lyell's estimates of the age of the earth were low, but as the concept of plate tectonics, with it's progressive recycling of rocks through subduction wasn't recognised, it was remarkably prescient.


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