<p>From <a href="http://dbforms.ga.gov.au/pls/www/geodx.strat_units.sch_full?wher=stratno=36957" rel="nofollow noreferrer">Australian Government- Geoscience AustraliaAustralian Stratigraphic Units Database</a>: </p>

<p><a href="http://dbforms.ga.gov.au/pls/www/geodx.strat_units.sch_full?wher=stratno=14834" rel="nofollow noreferrer">Panorama Formation:</a>  Paleoarchean min age: 3427 MA Age method: isotopic, U/Pb-Pb/Pb ion probe</p>

<p><a href="http://dbforms.ga.gov.au/pls/www/geodx.strat_units.sch_full?wher=stratno=36957" rel="nofollow noreferrer">Dresser Formation</a>: Min Age: Ma: 3477 Age method: inferred, overlying unit</p>

<p><a href="http://dbforms.ga.gov.au/pls/www/geodx.strat_units.sch_full?wher=stratno=26023" rel="nofollow noreferrer">McPhee Formation</a>:  Min Age: 3477 Age method: isotopic, U/Pb-Pb/Pb ion probe</p>

CC BY-SA 3.0
2017-09-19T20:58:43.113Z
Thanks! Not sure how I didn't know about that database, really useful to know.
Bertie Wheen
CC BY-SA 3.0
2017-09-19T21:01:23.903Z
So, it's from between 3477 Ma (min age at top) and 3481 Ma (max age at base)? Weird that I've seen quite a few people referring to it as being from 3490 Ma... I guess they're just mistaken? (Unless there was some older dating that still circulates, or some source isn't included in the database?)
Bertie Wheen
CC BY-SA 3.0
2017-09-20T07:17:33.460Z
@BertieWheen I've seen several articles (e. g. [Ueno et al 2008](http://doi.org/10.1016/j.gca.2008.08.026)) giving a 3.49Ga dating and they quote Thorpe et al. 1992. Constraints to models for Archaean lead evolution from precise U–Pb geochronology from the Marble Bar region, Pilbara Craton, Western Australia. In Glover, J.E., Ho, S. (Eds.), The Archaean: Terrains, Processes and Metallogeny. Geology Department and University Extension, The University of Western Australia, Publication 22, pp. 395–408. Unfortunately I do not have access to this publication to check.
plannapus
CC BY-SA 3.0
2017-09-20T08:54:46.090Z
@plannapus Good point. I can't get a copy of that conferences proceedings either, it seems it's not available at all online and you can only get it through some Australian libraries. I found another 1992 paper on dating the region by the same authors (_[U-Pb zircon geochronology of Archaean felsic units in the Marble Bar region, Pilbara Craton, Western Australia](http://www.sciencedirect.com/science/article/pii/0301926892901003)_) but it doesn't mention Dresser (as far as I could tell by a quick skim - in a bit of a hurry)
Bertie Wheen
CC BY-SA 3.0
2017-09-20T09:10:05.620Z
@BertieWheen In [Van Kranendonk et al. 2008](http://dx.doi.org/10.1016/j.precamres.2008.07.003), one can at least read this brief summary of the Thorpe et al. 1992 dating: `A Pb–Pb isochron age of 3490 Ma was obtained from galena in
barite of the chert–barite unit at North Pole (Thorpe et al., 1992b).`
plannapus
CC BY-SA 3.0
2017-09-20T10:51:50.810Z
@plannapus Oh! I downloaded that paper over a year ago, meant to read it but totally forgot about it. Thank you! Now I look at the ASU DB more closely, both Thorpe & Van Kran. are included (I stupidly hadn't scrolled down & found the refs as I was also in a hurry then... maybe I need to stop rushing around). So, I take it from the more recent referenced datings that 3490 Ma is no longer really realistic given that they seem to say it's from 3.48 Ga? (I suppose 3.49 might continue to be quoted partly because it makes stromatolites etc. that people find seem a little older?)
Bertie Wheen
CC BY-SA 3.0
2017-09-20T10:53:26.600Z
(apologies if these questions are trivial or tedious, geology really isn't my field - I only read about it intermittently)
Bertie Wheen
CC BY-SA 3.0
2017-09-19T14:09:42.563Z
2017-09-19T14:09:42.563Z
Earth Science Expatriate
<p>You could try........<a href="http://dmpbookshop.eruditetechnologies.com.au/product/the-pilbara-drilling-project-c-272-ga-tumbiana-formation-and-c-349-ga-dresser-formation-pilbara-craton-western-australia.do" rel="nofollow noreferrer">http://dmpbookshop.eruditetechnologies.com.au/product/the-pilbara-drilling-project-c-272-ga-tumbiana-formation-and-c-349-ga-dresser-formation-pilbara-craton-western-australia.do</a></p>

<p>And a few references in..<a href="http://geodocs.dmp.wa.gov.au/viewer/multipageViewerAction.do?documentId=440287&amp;viewMarkId=0&amp;ct=true&amp;at=none&amp;btv=true&amp;atv=false&amp;vmtv=false&amp;ac=ff0000&amp;cabinetId=1101&amp;pg=0&amp;scl=64&amp;bds=0|0|2560|3584" rel="nofollow noreferrer">http://geodocs.dmp.wa.gov.au/viewer/multipageViewerAction.do?documentId=440287&amp;viewMarkId=0&amp;ct=true&amp;at=none&amp;btv=true&amp;atv=false&amp;vmtv=false&amp;ac=ff0000&amp;cabinetId=1101&amp;pg=0&amp;scl=64&amp;bds=0|0|2560|3584</a></p>

CC BY-SA 3.0
2017-12-03T02:03:42.003Z
There is something wrong with the second link.
Fred
CC BY-SA 3.0
2017-12-03T09:56:51.273Z
Also, they are nothing more than links; not even titles. Link-only answers are not appreciated on SE sites. Can you include the essentials of that information in your answer here?
Jan Doggen
CC BY-SA 3.0
2017-12-03T00:17:28.987Z
2017-12-03T00:17:28.987Z
GregK
<p>I've seen many papers and sites that give the dating of Australia's Dresser Formation as 3.5 Ga (variously 3.48 or 3.49 Ga), but I can't seem to find the source of this.</p>

<p>Where does the dating come from, and what is it based on?</p>

<geology><dating>
Source of Dresser Formation 3.5 Ga dating
Bertie Wheen
# Source of Dresser Formation 3.5 Ga dating

(Asked by: username_0 on 2017-09-19)

I've seen many papers and sites that give the dating of Australia's Dresser Formation as 3.5 Ga (variously 3.48 or 3.49 Ga), but I can't seem to find the source of this.

Where does the dating come from, and what is it based on?

**Tags:** geology, dating


---

## 2 answers

### Answer by username_1 on 2017-09-19. Score: 3 | Accepted answer

From [Australian Government- Geoscience AustraliaAustralian Stratigraphic Units Database](http://dbforms.ga.gov.au/pls/www/geodx.strat_units.sch_full?wher=stratno=36957):

[Panorama Formation:](http://dbforms.ga.gov.au/pls/www/geodx.strat_units.sch_full?wher=stratno=14834) Paleoarchean min age: 3427 MA Age method: isotopic, U/Pb-Pb/Pb ion probe

[Dresser Formation](http://dbforms.ga.gov.au/pls/www/geodx.strat_units.sch_full?wher=stratno=36957): Min Age: Ma: 3477 Age method: inferred, overlying unit

[McPhee Formation](http://dbforms.ga.gov.au/pls/www/geodx.strat_units.sch_full?wher=stratno=26023): Min Age: 3477 Age method: isotopic, U/Pb-Pb/Pb ion probe

> **Comments:**
> **username_0**: Thanks! Not sure how I didn't know about that database, really useful to know.  
> **username_0**: So, it's from between 3477 Ma (min age at top) and 3481 Ma (max age at base)? Weird that I've seen quite a few people referring to it as being from 3490 Ma... I guess they're just mistaken? (Unless there was some older dating that still circulates, or some source isn't included in the database?)  
> **username_2**: @username_0 I've seen several articles (e. g. [Ueno et al 2008](http://doi.org/10.1016/j.gca.2008.08.026)) giving a 3.49Ga dating and they quote Thorpe et al. 1992. Constraints to models for Archaean lead evolution from precise U–Pb geochronology from the Marble Bar region, Pilbara Craton, Western Australia. In Glover, J.E., Ho, S. (Eds.), The Archaean: Terrains, Processes and Metallogeny. Geology Department and University Extension, The University of Western Australia, Publication 22, pp. 395–408. Unfortunately I do not have access to this publication to check.  
> **username_0**: @username_2 Good point. I can't get a copy of that conferences proceedings either, it seems it's not available at all online and you can only get it through some Australian libraries. I found another 1992 paper on dating the region by the same authors (_[U-Pb zircon geochronology of Archaean felsic units in the Marble Bar region, Pilbara Craton, Western Australia](http://www.sciencedirect.com/science/article/pii/0301926892901003)_) but it doesn't mention Dresser (as far as I could tell by a quick skim - in a bit of a hurry)  
> **username_2**: @username_0 In [Van Kranendonk et al. 2008](http://dx.doi.org/10.1016/j.precamres.2008.07.003), one can at least read this brief summary of the Thorpe et al. 1992 dating: `A Pb–Pb isochron age of 3490 Ma was obtained from galena in barite of the chert–barite unit at North Pole (Thorpe et al., 1992b).`  
> **username_0**: @username_2 Oh! I downloaded that paper over a year ago, meant to read it but totally forgot about it. Thank you! Now I look at the ASU DB more closely, both Thorpe & Van Kran. are included (I stupidly hadn't scrolled down & found the refs as I was also in a hurry then... maybe I need to stop rushing around). So, I take it from the more recent referenced datings that 3490 Ma is no longer really realistic given that they seem to say it's from 3.48 Ga? (I suppose 3.49 might continue to be quoted partly because it makes stromatolites etc. that people find seem a little older?)  
> **username_0**: (apologies if these questions are trivial or tedious, geology really isn't my field - I only read about it intermittently)  

---

### Answer by username_3 on 2017-12-03. Score: -1

You could try........<http://dmpbookshop.eruditetechnologies.com.au/product/the-pilbara-drilling-project-c-272-ga-tumbiana-formation-and-c-349-ga-dresser-formation-pilbara-craton-western-australia.do>

And a few references in..<http://geodocs.dmp.wa.gov.au/viewer/multipageViewerAction.do?documentId=440287&viewMarkId=0&ct=true&at=none&btv=true&atv=false&vmtv=false&ac=ff0000&cabinetId=1101&pg=0&scl=64&bds=0|0|2560|3584>

> **Comments:**
> **username_4**: There is something wrong with the second link.  
> **username_5**: Also, they are nothing more than links; not even titles. Link-only answers are not appreciated on SE sites. Can you include the essentials of that information in your answer here?  

---

