Can anyone help me identify these sandstone 'nodules' please?

[Badger Watching Man]

Hi there - I don't know if this is the right place for this post, but maybe someone can help me.

While walking on the Greensand Ridge in Bedfordshire I've been coming across 'nodules' of sandstone. These are typically an inch or so across, and either round or teardrop shaped.

The soil in the area is almost pure sand, but these are not just pebbles of sandstone. If you break one, they are hollow inside, and filled with fairly coarse sand grains.



They've got me puzzled as to what they are, and I cannot find out anything about them. Are they an ancient part of the sandstone, or did they form more recently?

If anyone knows, or has any suggestions, I'd be very grateful. These things are nagging at my curiousity!

Many thanks

[Highlander71]

Good find! I have walked the greesand ridge in Beds and not seen these nodules. I'm guessing but perhaps they are formed somehow by water action? Rain maybe percollating through and cementing the sand? Am willing to be proved wrong though

[Badger Watching Man]

Thanks!

They do seem to be cemented sand, so this makes sense, but the odd thing is that they're hollow, with loose sand inside. I'm trying to think of a process that would form a 'skin' around a patch of sand.

I've only ever found them in one particular spot, but that may be because I walk there regularly, or it may be something to do with the geology of the area.

Like I said, it's puzzling...

[Ukwildlifeo]

You know they do look like some solitary wasp/bee nests. I cant remember what type, but it would account for the cemented wall and hollow interior. So if the bee/wasp dug out and cemented a chamber and then later the soft sand eroded, it would leave just these cemented 'nodules'. Its an idea at least!

[Badger Watching Man]

It's a very interesting idea! I hadn't thought of a biological rather than a geological explanation.

I've seen the holes of solitary bees/wasps in the area, so it is perfectly possible. My only reservation is that these nodules are entirely sealed - there's no hole for the wasp/bee to get out of. Does anyone know if bees/wasps make completely sealed chambers?

[Highlander71]

Sounds very reasonable to me, hadn't thought of a biological cause. Hopefully someone on here can enlighten us?

[Ukwildlifeo]

Originally Posted by Badger Watching Man

It's a very interesting idea! I hadn't thought of a biological rather than a geological explanation.

I've seen the holes of solitary bees/wasps in the area, so it is perfectly possible. My only reservation is that these nodules are entirely sealed - there's no hole for the wasp/bee to get out of. Does anyone know if bees/wasps make completely sealed chambers?

I believe it works like this: the solitary adult builds a 'nest', collects and stores some food in the nest and then lays an egg before seeling it off so the larva can grow in piece - but then when that reaches the adult stage it has to make a hole to get out. Perhaps it didnt grow up or the hole has re seeled or something.

It might be an idea to post a link to this thread in a new thread in the insect section

[Lance Morgan]

I'm sure your almost there
How about this.....
Wasp burrows and forms this 'nest' leaves egg anfood and seals it. mature wasp hatches and burrows out surrounding sand falls or is blown back in by wind and fills the void. Erosion/wind and wet act to leave these pods visible
Anyway they certainly look like the work of a burrowing solitary wasp

[lol geoff]

Iron age scotch eggs? Perhaps the egg has rotted leaving the petrified remains of the sausage meat and breadcrumbs.

[Meta menardi]

Originally Posted by lol geoff

Iron age scotch eggs? Perhaps the egg has rotted leaving the petrified remains of the sausage meat and breadcrumbs.

I don't think that would account for the sand inside the sausage meat remnant, but I like the way you are thinking.