there are places in the sea that it so briney, that it kills most organisms , but usually extremophiles can survive said salt concentrations and can feed on carcasses, usually halophiles, most are archaea and some bacteria.

The sea is not “a salt brine in itself”. You need a much higher salt concentration to pickle anything than what you find at any point in the ocean. Enough to prevent microbial life forms from surviving and consuming whatever it is you’re trying to pickle, which is why it doesn’t rot while pickling.

If a dead thing would pickle, pretty much everything in the sea would end up pickled alive

There are pockets and layers of water in the ocean that behave very differently from each other. There are areas of high salt concentration that pretty much act as death horizons for many organisms. There are waters completely devoid of oxygen that suffocate organisms that get lost or stuck in it.

So, in a sense: yes. However the degree to which marine life had adapted to these conditions, the more unlikely parameter is a dead organism not being consumed by scavengers.

Isn’t that just what a fossil is? If you get a little creative about how you define pickling?

That wouldn’t be very typickle.

The ocean is absolutely PACKED with life like bacteria, viruses, and other microscopic organisms. Even if the salinity is high, it’s unlikely that you would get an ideal “pickling.” Hypothetically, if were there very few of those around for some reason, maybe? Maybe for a little bit. A more likely situation may be one where an organism was eventually fossilized due to being covered by something. And we ALL know being fossilized is better than being pickled, right?

Depends on the conditions, I’d say. If you have an area that has low oxygen and high saline concentration, one could potentially preserve large parts of the carcass. A big challenge though is the substances brought by the carcass itself, like enzymes and bacteria that are not directly exposed to the oxygen-deficient saline-abundant water, which can thrive and remain active for a long period of time. However, if this carcass sinks to incredible depths, where the pressure is really high, temperature is a constant 4 degrees, very low concentration of scavengers or thriving organisms, and potentially sinks a bit into the sediment for a long time, you’ll essentially get pickle juice fossil fuel.

Every multicellular creature lives in symbiosis with a plethora of bacteria, inside and outside of its system, those will always be the first to start decomposition. You’d need extreme conditions to sterilize those and avoid decomposition, and even then, there’s pretty much not a cubic millimeter in the ocean that isn’t filled with other bacteria and fungi.

Maybe in a brine pool but in most parts of the ocean the salt is not concentrated enough

out of curiosity what is the average salinity? We often use 0.85% saline to suspend organisms and red cells to keep osmotic pressure stable, I’m just curious if its around that level.

Idk, but dead whales become an entire ecosystem. They’re called “whale fall” https://en.m.wikipedia.org/wiki/Whale_fall

I’m no expert in the field, but under the right conditions, possibly. But that would also be incredibly unlikely. The oceans are so full of life that something would feed on the remains, and even if not it would be more likely to decompose than be preserved. Bacteria is everywhere, including in the ocean, and bacteria is a significant component in decomposition.

I believe the brine solution we use for preserving food is a much higher salt concentration than sea water.