Fossiliferous strata near Lake Titicaca (Bolivia) 4/4

[Pierre-Olivier Combelles]

I lived several years in Bolivia, doing botany, ethnobotany, agronomy and agriculture. On december 28th, 1998, travelling in my car with my family around Lake Titicaca, I took these pictures of magnificent fossiliferous marny strata on the side of the road between the strait of Tiquina https://en.wikipedia.org/wiki/Strait_of_Tiquina  and Copacabana (Tiquina is between Huarina on the map and Copacabana), on the bolivian southern side of the lake. Geologically, this area seems to belong to Devonian. 

What do you think about this ? As being not paleontologist, it would interest me. Thanks in advance for your remarks.

* I remember that In the 1990' and 2000', one could purchase in the streets of La Paz, as I saw it many times,  fake Trilobits made of black terracota by Aymara people (traders in the soul and skilful crafts men) very, very nice and accurates and certainly made by moulding. This kind of geological site was perhaps a source o inspiration for them...

Edited August 9, 2017 by Pierre-Olivier Combelles
Title and precisions in the text

[Pierre-Olivier Combelles]

[Pierre-Olivier Combelles]

[Pierre-Olivier Combelles]

Sorry for the bad quality of my pictures. I have scanned my old photos printed on paper.

[izak_]

Are these from the same site as your first post? If so, it would be better if you put all the photos from this place on your original post.

[Pierre-Olivier Combelles]

1 minute ago, Foozil said:

Are these from the same site as your first post? If so, it would be better if you put all the photos from this place on your original post.

Yes, all are from the same site. Size of the photos too heavy to put on the same post. Sorry.

[FossilDAWG]

I have merged the 4 posts into one to keep everything in one place.

 

Don

[Pierre-Olivier Combelles]

OK if you can help me. Thanks !

[FossilDAWG]

Very interesting topic, we do not often see examples of the geology from that part of the world.  Unfortunately the photos are not close/detailed enough to allow identification of individual fossils, but large trace fossils are quite evident.

 

Don

[Miocene_Mason]

Looks like something's found in the Devonian, as previously said some things are not close enough to ID but the shells remind me of chonetids and trace fossils are common in the Devonian (well really they have been and always are common). I've heard of Devonian fossils in Bolivia, and I think I read a paper on its ichnofossils (bifungites in particular, I had found some myself in Maryland). Very interesting, maybe someday I'll make it there.

[Pierre-Olivier Combelles]

I still have the negative films of these photos. I shall see if we have a better result scanning them instead of the prints to have a better definition. Not sure... 

[Pierre-Olivier Combelles]

A reconstitution of the Planet during the Middle Devonian.

By Stampfli & Borel 2000 - This image comes from the Tethyan Plate Tectonic working group of the Institut de Mineralogie et Petrographie, Université de Lausanne. They give permission for "If you use the following reconstruction please make reference either to this web-page and/or to the references mentioned below!" (permission). Original picture, Attribution, https://commons.wikimedia.org/w/index.php?curid=3489312

[abyssunder]

This image reminds me of a Cruziana ichnofacies, but I could be wrong. Try to remember the shapes and details of the traces and compare with the pictures from the highlighted link.

 

[Pierre-Olivier Combelles]

Thank you very much Abyssunder!

Certainly you are right!

Yesterday, I have asked Thierry Sempéré, a french geologist specialist of the morphology of the Andes, retired from IRD, about this fossils

http://www.perou.ird.fr/nos-activites/programmes-de-recherche/sciences-de-la-terre/histoire-et-anatomie-des-andes-peruviens-et-applications-a-l-exploration-de-ressources-naturelles#

and he replies:

"Concernant les traces fossiles du quatrième point, il ne s'agit que de bioturbations, certaines silicifiées, qui ne peuvent apporter d'informations très précises."

So, he acknowledges for Cruziana (fossil paths of prehistoric animals like Trilobites). 

With him, we shall ask some other specialists to get more informations, if I can localize the site with more precision (twenty years ago...), respect to the stratigraphy.

Best regards