Trace fossils on Upper Jurassic sandstone

[Aerson]

Hello people of ichnology.

 

I'm studying a Rift basin in Brazil Northeast, related to African-American break-up of Gondwana.

This unit is mostly composed of braided river deposits (coarse sandstone and conglomerate) interbedded with paleosols.

Due to high deforestation of the region, this area is in being eroded and losing considerable mass, and oftenly new outcrops are formed.

Considering this, I bring to you a concern for the identification of some trace fossils that appeared, in order to manage strategies to prevend it's destruction.

 

In the left corner of this image, the person serves as scale. The scale person is standing on the studied bedding surface.

 

This is the general view of the bedding surface. The bed is composed of fine to medium sandstone, never coarse, which indicates very low water flow. Ripple marks are seen, and the scale card indicates paleoflow direction. Also, mudcracks are abundant, which indicate seasonal climate. The dark oxidized rims and the rambling trails and tracks are interpreted to be trace fossils.

 

The dark rims are penetrative structures with 7 to 14 cm deep, previously seen in the unit and interpreted as small scale lungfish aestivation burrows, which is in accordance with the hot and seasonally dry Jurassic climatic context for West Gondwana.

The novelty of this outcrop is the appearance of a surficial multitude of tubular tracks and trails, 0.5 to 1.0 cm wide, 10 to 50 cm long, that randomly cross each other.

 

I wonder if you guys could help me with the following questions:

 

-> Is there an ID for the presented ichnogenera?

-> Any thoughts on the possible burrow architect groups?
-> Could this bedding be marked as an ichnofacies, or is this concept outdated?

 

Thanks in advance!

Att
 

[jpc]

I do not have answers for you but keep your eyes open for pterosaur tracks in this stuff.