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9/2/16 trip to Chatsworth Consauga formation Cambrian: I finally did it!


MeargleSchmeargl

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So, I finally did it. Since this weekend was labor day weekend and we didn't have any other plans laid out for Saturday, I made my dream trip to Chatsworth a reality. The official time it was supposed to take to get to the site according to google maps was one and a half hours, although it felt like less time, despite GPS blunders along the way. After successfully finding the destination on Tibbs Bridge road, I wasted no time in making my steady way down the path from the bridge to the slowly flowing Consauga river, eagerly pursuing the trilobites below. I was immediately scanning the ground when I reached the bottom of the hill:

 

2016-09-03 20.32.42.png

2016-09-03 20.34.51.png

2016-09-03 20.35.30.png

 

 

To be continued...

 

 

 

Every single fossil you see is a miracle set in stone, and should be treated as such.

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...Continued

 

It did not take me very long to find my first trilo:

 

2016-09-03 20.34.03.png

 

After some time I moved up formation to be greeted with greater success:

 

2016-09-03 20.36.20.png

 

After a good hour of hunting the site and selecting the best specimens to take home, we retreated back to the city for a refreshing Chick-Fil-A smoothie. Upon arrival, I took a closer look at my new additions to my collection. 

 

Here is a haul family photo:

 

2016-09-03 19.47.12.png

 

To be continued...

 

 

Every single fossil you see is a miracle set in stone, and should be treated as such.

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The first Trilo in the spotlight is the biggest of the bunch, with positive and negative halves.

 

Thumb comparison:

 

2016-09-03 21.09.53.png

 

Negative closeup:2016-09-03 19.34.27.png

 

 

Positive closeup:

 

2016-09-03 19.35.11.png

 

The next trilo is an interesting phenomenon, with an outline around the actual trilo somewhat resembling trilos from much later.

 

Thumb comparison:

 

2016-09-03 19.36.04.png

 

To be continued...

Every single fossil you see is a miracle set in stone, and should be treated as such.

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...Continued

 

Negative closeup:

 

 

2016-09-03 19.37.02.png

 

Positive closeup:

 

2016-09-03 19.37.53.png

 

The second to last trilo is one of the two which I considered FOTM worthy  This is a small one, but with nice detail.

 

Thumb comparison:

 

2016-09-03 19.39.01.png

 

Negative closeup:

 

2016-09-03 19.43.14.png

 

To be continued...

Every single fossil you see is a miracle set in stone, and should be treated as such.

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...Continued

 

Positive closeup:

 

2016-09-03 19.43.58.png

 

And finally, the last trilo(s) which I am considering for FOTM is one with a particular amount of detail in the thorax segments.

 

Thumb Comparison:

 

2016-09-03 19.46.38.png

 

Closeup: 2016-09-03 19.44.57.png

 

And a closeup of the particularly FOTM worthy trilo:

 

2016-09-03 19.45.58.png

 

And that just about sums up my trip to chatsworth! Not entirely being the trilo expert (at all), I would appreciate any accurate IDs, especially for my very early FOTM considerations. Thanks for reading!

Every single fossil you see is a miracle set in stone, and should be treated as such.

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Great report and finds!

Thanks for sharing it with us - glad you got out there.

@piranha Should be able to help with ID's. :)

Regards,

 

 

EDIT - FossilDawg noted that  Aphelaspis brachyphasis   was the trilobite found at that site.

    Tim    -  VETERAN SHALE SPLITTER

   MOTM.png.61350469b02f439fd4d5d77c2c69da85.png      PaleoPartner.png.30c01982e09b0cc0b7d9d6a7a21f56c6.png.a600039856933851eeea617ca3f2d15f.png     Postmaster1.jpg.900efa599049929531fa81981f028e24.jpg    VFOTM.png.f1b09c78bf88298b009b0da14ef44cf0.png  VFOTM  --- APRIL - 2015  

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2 minutes ago, Fossildude19 said:

Great report and finds!

Thanks for sharing it with us - glad you got out there.

@piranha Should be able to help with ID's. :)

Regards,

Thanks :D

Can't wait for piranha to come around, then!

Every single fossil you see is a miracle set in stone, and should be treated as such.

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Congratulations! Always fun seeing trilos from an unusual location. Do you know the age/stage more specifically?

Who is 'we' - you and who?

 

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Elrathia antiquata looks like a good match. Attached for comparison are some examples from Schwimmer 1989.

IMG1.jpg

figures from:
 
Schwimmer, D.R. (1989)
Taxonomy and biostratigraphic significance of some Middle Cambrian trilobites from the Conasauga Formation in western Georgia.
Journal of Paleontology, 63(4)484-494

PDF LINK

 

 

 

 

  • I found this Informative 2

image.png.a84de26dad44fb03836a743755df237c.png

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1 hour ago, Wrangellian said:

Congratulations! Always fun seeing trilos from an unusual location. Do you know the age/stage more specifically?

Who is 'we' - you and who?

 

I went with my grandfather. Also, the trilos from Chatsworth are 502 myo. Guzhangian age.

Every single fossil you see is a miracle set in stone, and should be treated as such.

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36 minutes ago, piranha said:

Elrathia antiquata looks like a good match. Attachedidfor comparison are some examples from Schwimmer 1989.

IMG1.jpg

figures from:
 
Schwimmer, D.R. (1989)
Taxonomy and biostratigraphic significance of some Middle Cambrian trilobites from the Conasauga Formation in western Georgia.
Journal of Paleontology, 63(4)484-494

PDF LINK

 

 

 

 

Yep, sure looks like It. Other photos on the web when I searched this showed results that look almost Identical to my specimens.

Every single fossil you see is a miracle set in stone, and should be treated as such.

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19 hours ago, MeargleSchmeargl said:

I went with my grandfather. Also, the trilos from Chatsworth are 502 myo. Guzhangian age.

That's the kind of info I like, thanks... That would be equivalent to the Upper Marjumian stage in the North American system.

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19 hours ago, MeargleSchmeargl said:

I went with my grandfather. Also, the trilos from Chatsworth are 502 myo. Guzhangian age.

 

14 minutes ago, Wrangellian said:

That's the kind of info I like, thanks... That would be equivalent to the Upper Marjumian stage in the North American system.

 

 

502 Mya is actually Drumian Stage. But hey, what's a couple million years among friends? :P

 

IMG1.jpg

 

chart from:

 

Gradstein, F.M., Ogg, J.G., & Schmitz, M. eds. (2012)
The Geologic Time Scale 2012, 2-volume set.
Elsevier Scientific Publishing, 1176 pp.

 

 

  • I found this Informative 2

image.png.a84de26dad44fb03836a743755df237c.png

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56 minutes ago, piranha said:

 

 

 

502 Mya is actually Drumian Stage. But hey, what's a couple million years among friends? :P

 

IMG1.jpg

 

chart from:

 

Gradstein, F.M., Ogg, J.G., & Schmitz, M. eds. (2012)
The Geologic Time Scale 2012, 2-volume set.
Elsevier Scientific Publishing, 1176 pp.

 

 

Well, the more ya know xD

Every single fossil you see is a miracle set in stone, and should be treated as such.

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The paper I linked earlier dealt with this specific site.  Here is the link againElrathia is not present, the common trilobite is Aphelaspis brachyphasis.  Admittedly the two trilobites are very similar, in fact the trilobite is misidentified as Elrathia antiquata in handouts I have seen for field trips from the geology department at UGA and other area colleges.  One could never hope to distinguish them based on MeargleSchmeargl's photos.  Here are photos of Aphelaspis brachyphasis from the Schwimmer & Montante (2012) paper (Southeastern Geology V. 49 p. 31-41.):

Aphelaspis .jpg

Also it is noteworthy that the agnostid trilobites Glyptagnostus reticulatus, Agnostus inexpectans, and Aspidagnostus rugosus occur at the site (they are small and easily overlooked unless you are specifically looking for them).  Glyptagnostus reticulatus is a biozone marker with worldwide occurrence in the Pabian (Upper Cambrian), coincident with the base of the Aphelaspis biozone.  Glyptagnostus (and the other agnostid species) do not occur in the older Drumian, and are never found associated with Elrathia.

Don

 

 

.
Edited by FossilDAWG
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8 minutes ago, FossilDAWG said:

...One could never hope to distinguish them based on MeargleSchmeargl's photos...

 

 

I agree.  Before posting I looked very closely at the A. brachyphasis figures and finally decided that E. antiquata was a better match.  

 

Luckily, you were familiar with the locality to clear this up.

 

 

 

image.png.a84de26dad44fb03836a743755df237c.png

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2 hours ago, piranha said:

 

 

 

502 Mya is actually Drumian Stage. But hey, what's a couple million years among friends? :P

 

IMG1.jpg

 

chart from:

 

Gradstein, F.M., Ogg, J.G., & Schmitz, M. eds. (2012)
The Geologic Time Scale 2012, 2-volume set.
Elsevier Scientific Publishing, 1176 pp.

 

 

That chart doesn't include the Drumian under the North American sequence, it's included in the Marjumian. I was going by the NA sequence, comparing it to MS's statement about the Guzhangian (which is above the Drumian, but also later than 502my, I notice. Which is correct?)

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32 minutes ago, Wrangellian said:

That chart doesn't include the Drumian under the North American sequence, it's included in the Marjumian. I was going by the NA sequence, comparing it to MS's statement about the Guzhangian (which is above the Drumian, but also later than 502my, I notice. Which is correct?)

 

 

According to the chart the Drumian and Guzhangian stages each correlate within the Marjuman.  I was only pointing out the Drumian is actually 502 Mya, currently set at 500.5 - 504.5 Mya.  The paper that Don linked above, confirms this locality is late Middle Cambrian (Series 3: Drumian).

 

 

 

  • I found this Informative 1

image.png.a84de26dad44fb03836a743755df237c.png

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OK so the site is not Guzhangian, it's Lower Marjumian (North American scale) or Drumian (world scale)... MS might like to know that.

Edited by Wrangellian
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