Why do terrain tiles form and is there a way to prevent it?

[Kasuha]

This is my polluted oxygen condenser. After some time of flawless operation, a terrain tile of solid oxygen formed in it in mid-air. The screenshot is from a bit later when I already took steps to make the thing serviceable, building a door and some ladders to give my dupes access all around the machine to dig any potential future oxygen tiles that may form there. But I'm surprised it appeared there at all, I believe such things are not supposed to happen. Similar thing but with solid CO2 tiles happened to my CO2 condenser. Any ideas about it?

[PVD]

Sometimes(I guess most times) tiles turning into solid blocks during solidifying, I'm also interested to know conditions for it to happen and how to prevent it(sure the first one is temperature)

[Xanif22]

I always get CO2 doing this when I reload

[PVD]

Okay, here is first tests. When liquid is going to solidify result density plays role. If current liquid density <= target.density / 1.25 then drop else solid block.

Let's perform test on liquid oxygen, water, liquid carbon dioxide.

1. Solid oxygen has 300 kg/m density, theoretically than means <= 240 (300 / 1.25) kg liquid oxygen will go to drop, result:
2. Ice density = 1000 kg/m, 800 (1000/1.25) kg for drop:
3. Solid CO2 has 600 kg/m density, 480(600/1.25) kg for drop:
4. Okay, and on more sweet test, Tungsten 200 kg/m, 160 kg of melted Wolframite for drop:

According to tests, theory seems to be right. So, theoretically using this we can mine x2 of any material! Just turn into liquid, increase pool and be sure that density is lower than target / 1.25 and have nice solid drop. But in practice it will not work, because most materials transform chemically when become liquid, e.g. wolframite->tungsten, granite,obsidian,sandstone etc.->igneous rock, gold amalgam -> gold, etc. refined metals still not usable, minerals loose their properties, only seems valuable for H20, CO2, something that you can feed to your hatches and that is already in liquid state (also sweet for steel, but it is another story...)

Also. It does not explain why it solidify in your case, as I see your block has really small density... So there might be some another mechanic which I not discovered yet (maybe falling liquids?) or maybe a bug.

[Kasuha]

1 hour ago, PVD said:

as I see your block has really small density...

I think the description lies. When I dug a tile of solid CO2 that was supposed to be a few grams, it left a chunk of about 200 kg of solid CO2.

[Masterpintsman]

4 hours ago, Kasuha said:

I think the description lies. When I dug a tile of solid CO2 that was supposed to be a few grams, it left a chunk of about 200 kg of solid CO2.

Most likely you missed the 'buried object' part of the info on your tile.