Maybe some fresh eyes on a old question... What are these "mud mounds"?

[Bucket Lister]

Sir I have no idea what you are referencing concerning "overburden".

o·ver·bur·den

noun: overburden
/ˈōvərˌbərd(ə)n/

1. rock or soil overlying a mineral deposit, archaeological site, or other underground feature.

 

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[Limitool]

Concerning the stalactite picture.
It appears as if the base is hanging in mid air?

Is the base resting on the ground or is it connected only at the top?

Your right.... it's hanging in mid air. That one and the small ones around it are the ONLY ones I ever saw. But this pic was taken near the very end of the cave. I went maybe another 15 minutes on my stomach and couldn't even turn around. Had to crawl backwards.

 

[Limitool]

o·ver·bur·den

noun: overburden
/ˈōvərˌbərd(ə)n/

1. rock or soil overlying a mineral deposit, archaeological site, or other underground feature.

Very little which leads to where did all that mud come from or HOW were these mounds made. Especially the very squared up one much deeper in cave with a tunnel behind it.

 

[Armchair detective]

Getting a picture of a cave formed by a "gully washer" rainstorm in a riverbed.
Mud mostly washed out it leaving a layer on the back walls.
Then a drying out. Mud shrinks, makes squarish mud blocks.
Whaddya think?

 

[searcher]

Your right.... it's hanging in mid air. That one and the small ones around it are the ONLY ones I ever saw. But this pic was taken near the very end of the cave. I went maybe another 15 minutes on my stomach and couldn't even turn around. Had to crawl backwards.

Finding stalactites that are hanging in mid air indicates-
1-The floor has dropped/fallen.
2-The floor has been washed out. Usually not even. Has ruts and dips like a small grand canyon. It can be smooth if it washes to the next rock layer. But it usually shows water wear on that next layer.
3-The ceiling has pulled up. This is rare but I've seen a couple places that this has happened.
4-Part of the stalactite has been taken.

From the other pictures of the squares and the stalactites.
It appears that most of the cave floor/rock layer has fallen.
The floor pulled loose from the stalactites because they were attached to tumble down(rocks/debris that has fallen from the ceiling) or sediment.
The floor falling made headspace above the blocks of whatever-they-are.
Then the floor was washed by the flowing stream.

This is all surmise of course. Based on other caves I have explored/studied.

It does appear that this cave was mined or dug in at some time. Squared off sides of debris piles, marks on the walls,etc.
Why and when has yet to be determined.

Edits for clarity

 

[Limitool]

Getting a picture of a cave formed by a "gully washer" rainstorm in a riverbed.
Mud mostly washed out it leaving a layer on the back walls.
Then a drying out. Mud shrinks, makes squarish mud blocks.
Whaddya think?

Well you might be right...? But a "gully washer" wouldn't leave behind a mound like this. And it's right in front of a tunnel blocking the entrance as you can see. Even the back of this mound has 90 degree angles like the sides and front. The artisan well is just a little ways upstream from this mound. We had very bad horrific floods around here in 2010. After the floods resided I went back and a huge landslide had came right over the top of the cave entrance. There was enough room to get in yet. Nothing had changed within cave. But I can't stress it enough how hard it is to just reach this area of cave. And it gets harder still just to the right of this mound photo. I'm squeezing through to back half of cave. My back is scraping the ceiling, my stomach flat on bottom and head turned to keep out of the water to breath. Then add 10-15 yards like that. Opens up into a small sit down room.