Fossilized hole

[Rockwood]

Is this a burrow ?

I'm sort of leaning toward it being a fluid or gas venting feature myself. 

It was found on the shore of Moosehead Lake just south of where the fossiliferous, upper Silurian, Forks turbidite crosses it. The breaks are likely caused by the thrust of ice as it forms and expands against the shoreline in that spot. Car sized boulders can be displaced several feet by the force.

The blue line indicates roughly the position of the hole. It passes all the way through, with a slight bend and constriction in the center.

[abyssunder]

It's really hard to say after 50 views of no reply, and I don't know what it could be, but the 'borrow' (in my thinking) might be caused by the drop in fluid pressure perpendicular to the joint surface which looks like this:

 

 

 

correction: lateral to the joint plate

Edited December 10, 2017 by abyssunder

[Rockwood]

4 hours ago, abyssunder said:

It's really hard to say

Thanks for the thought. We seem to be sort of on the same page.

Glaciers can be helpful at extraction, but they are not good with documentation.

[Ludwigia]

I think that burrows, at least under normal circumstances, come in groups. If it is one, it must be the solitary remainder of a long distance runner, but I'm more inclined to the tectonic solution to your question, although I can't add any new suggestions.

[supertramp]

10 hours ago, abyssunder said:

It's really hard to say after 50 views of no reply, and I don't know what it could be, but the 'borrow' (in my thinking) might be caused by the drop in fluid pressure perpendicular to the joint surface which looks like this:

 

 

 

correction: lateral to the joint plate

 

mmh...the presence of an oxidation coating at the circular edge of the cavity (picture n. 5) suggests that the hole was preexisting; moreover, the fracture must have originated by a brittle mechanism, whereas the hole itself was probably formed within an unconsolidated sediment.

Really strange pattern…the only thing  that comes to my mind is some sort of a (rare?) cylindrical sedimentary dyke, or an injection/suction structure, with the infilling material then eroded.

ciao

 

https://www.google.it/search?q=clastic+dyke&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjcqd-6yP_XAhVCNxQKHSqpDWwQ_AUICigB&biw=1517&bih=707

[caldigger]

"Holy petrification Batman!"  i know this does't help you, but it just came into my head and I could't stop myself.

[Rockwood]

1 hour ago, supertramp said:

the fracture must have originated by a brittle mechanism, whereas the hole itself was probably formed within an unconsolidated sediment.

 

 

 

 

I'm fairly confident that the fractures are more recent than the latest ice age even.

The lake is used as a hydro reservoir, and for fisheries management purposes they often lower the level of water as the ice is forming. Between the expansion of the crystallizing sheet and the weight of it dropping against it's groundings things can get violent. 

I was amazed that some camp owner would spend a fortune setting of fireworks on a cold cloudy December day, but when I walked down to the shoreline I realized it was like a rolling fracture of the ice following the shoreline.