[moe]

Extending on the cylinder idea, how about a cone?

My naive thinking would be a cone with a large diameter and a relatively small hole at the top. Plug a hose (or rather a pipe) into that hole and suck off the oil into tankers faster than it would push out on the sides at the bottom of the cone.

This could surely not catch all of the stream, but perhaps a worthwhile percentage?

[ars]

They tried that. The cone floated away.

The oil is much lighter than water. Plus it has methane which is even lighter than that.