Strange textured rock

[fumanchuck]

Hi All, 

 

First post for me. Excited to participate! I have recently taken up fossil hunting in Edmonton, Alberta, Canada's river valley creek beds.

I have found several fossilized bone fragments, petrified wood fragments and even a few first nations artifacts.

All of these have been found on small creek  bed shelves during low water. The geological time period is mesozoic.

 

The first object I would appreciate any feedback on is an irregularly textured flat rock or potentially a fossil of some kind. It was found loose on the surface next to the water. It has an interesting varied texture which differs on both sides. It doesn't seem to present the kind of regular pattern that would indicate a shell or skin, but there appears to be some degree of regularity or patterning. It kind of looks like a piece of beef jerky. At first I thought it might be from dried mud cracks but the patterning does not reflect this. Any thoughts on this would be appreciated. 

 

[supertramp]

something like "boxwork", I think.

ciao

[Rockwood]

I suspect these are fractures in what is essentially an extinct aquifer. 

[fumanchuck]

how interesting to learn about boxwork and the fractured rock aquifers. Thanks for your feedback!