Oil spills and leaks tend to dissipate eventually via several mechanisms. A storm will generally assist in dispersal. Given that it's the concentration of oil that is most harmful to life in the region, this is generally helpful.
Spilled oil consists of volatile and heavy elements. The volatile elements tend to evaporate, the heavy fractions eventually sink to the sea floor. (They can of course cause further damage there, as benthic damage resulting from the Deepwater Horizons spill attests.) Surface oil may also burn (as seems to be occurring here.) Some 20--40% of the mass of a slick may evaporate into the atmosphere. Some of the oil is water-soluble and will mix with the water column at depth, while 10--30% falls to or mixes with sediments on the seafloor.
Oil can also be washed onto shorlines --- beaches and rocks. Here it will mix with or coat sand and rocks. This is highly visible, but usually only a small fraction of the total spill volume. Wildlife, particularly birds, tend to be strongly and visibly affected.
At the surface, oil forms a slick. Wind and wave action tend to spread and disperse this, mixing the oil with the water column. Lighter fractions will eventually rise.
Managed responses to oil spills include skimming (booms and absorbants), burning (of concentrated oil), and dispersion (of widely-distributed oil). Skimming and burning where possible do remove the oil from the water column relatively quickly. The record on dispersants, which tend to be chemical-based agents themselves affecting sea life in the area, is more mixed. None of these methods are applicable to tropical-storm (or worse) conditions. Note that the spill in question here is far out of any possible track of Hurricane Elsa.
just what i need for my climate catastrophe anxiety...
question: is it better for the oil to burn up? i'm sure not all of it makes it to the surface, but maybe better than dispersing in the water where we'd never get it out?
In general, yes, as this rapidly removes much of the oil from the water column. The results of combustion are CO2 and water, as well as soot and partially-burned hydrocarbons. The amount of light elements on the surface and mixed into the water column are reduced, though there may still be substantial seafloor contamination from heavier components or partially-combusted material which sinks.
From the videos I've seen, I'd suspect a fair amount of natural gas in the leak, which is typical of at least some oil fields in the area. More so near Trinidad and Tobago, which is not exactly close to the field in question.
I've also read back with the last giant spill that the chemicals they use to 'clean up' really just break the oil down into smaller droplets so it falls to the floor. if that's true it almost sounds worse like micro plastics.
I don't think anyone can answer that question based on first principles. It looks like the perfect conditions for incomplete combustion with aerosolized petroleum violently mixing with sea water that's getting rapidly pushed away by the force of the explosion.
On on the one hand, it might spread out the petroleum and prevent an oil slick from forming, making it less ecologically damaging. On the other hand, it might be combusting a negligible amount of the fuel and spreading the rest as tiny particles that aren't small enough to overcome a turbulent sea and collect at the surface, so they enter the respiratory and digestive systems of everything in the gulf.
