Drinking a wine tonight that has a distinct aroma of the sea. Specifically, stagnant sea water like you would get on a warm day in a calm tidepool. Interestingly, when I google “ocean smell”, one of the hits is some research that concludes one of the dominant compounds responsible is dimethylsufide (CH₃)₂S, a common wine flaw. Though in this case, I think there is more to the aroma, this isn’t just a rotten cabbage smell. Guess I need to find some DMS and find out exactly what it smells like. Doesn’t sound fun.
This is red wine, I take it??
I’d guess some sort of reduction. Although a dead critter in a tide pool might add a but of terroir brett 
Yes.
My feeling is reduction. I get that “saline”(term I use when it’s my wine) note from some of the early release white wines as well. It does evolve out though which dimethyl-sulphide usually is somewhat stubborn.
How reductive compounds smell (from my reading, and anecdotal experience) are very dependent on the concentration. I.e. higher concentrations can be completely different, and often disgusting, than lower concentrations.
I’d say it’s a reduction thing, not Brett. Eric’s comment about concentrations makes sense to me too.
Reduction, or sulphur compounds, is responsible for a lot of characters that people think of as minerality.
DMS is reduction, and yes, it does smell of the sea.
Following up, the wine cleaned up nicely after some air time. So I’ll conclude this was DMS contamination, which can oxidize (or maybe just blow off?) to DMSO, an odorless compound.
Neither. Your terms are too limiting. If you truly want the smell of seawater, seaspray, or what have you, drink a Muscadet or a Colares (red or white).
I drink a fair amount of Muscadet, and have never smelled this aroma in one. I can get “sea spray” on a number of wines (Muscadet can be one, but notably Chablis), but it never devolves to a negative level this bottle was at. I’m 90% convinced this particular case was DMS.
Sea spray is different from stagnant tide pool, which is probably mostly rotting seaweed.
Sounds like a dimercaptan issue. I remember very early on in my wine making career I was served some Chardonnay at a winemaker luncheon for an unnamed producer that smelled exactly like a tuna fish sandwich. It was an interesting learning experience.
Hydrogen sulfide is one of the distinctive components of the aroma of a salt marsh, which I strongly associate with the ocean and which isn’t that uncommon as a wine fault.
+1 with the Colares.
Thanks Joe. This wasn’t tuna fish. I am finely attunad to that aroma, as I despise the stuff 
I’ll note this for future reference.
Thanks for the suggestion, Mike. This wasn’t H2S, which everyone should be familiar with as the smell of “rotten” eggs (also not that uncommon in hard-boiled eggs). Agree it is common in salt marshes, which we have a lot of in the Bay Area. I drive across the Bay routinely, and in warmer, still weather, the enclosed marshes can have a very strong H2S smell.
I think you have it spot on, Alan. I quite like it and it often blows off. Pretty common in wines from schist soils in the languedocroussillon
DMSO, while odorless, will absorb through the skin instantly and impart a garlic taste in the mouth.
Interesting. I often get that saline thing. I never associated it with reduction.
Jason