There was a film of oil on water.

水面上浮有一层薄薄的油。

youdao

If you pour oil on water, it floats.

油脂必定水面浮，真理最终占上风。

youdao

June 2010: oil on water has many appearances, at least part of the oil slick is pale grey.

2010年6月7日：海域上出现有大量的浮油。部分浮油呈现淡灰色。

youdao

"The Obama moratorium on deep water oil drilling has already cost tens of thousands of jobs."

VOA: standard.2010.07.31

"Oil floats on water, and so you get the buoyancy or lift.

VOA: standard.2010.06.21

But could find none. "Over time oil does dissipate and can get broken down from bacteria and other organisms in the water, but still they are putting certain dispersants on the oil that makes it sink down to the bottom."

VOA: standard.2010.05.09

Salicornia produces a high quality vegetable oil on sea water.

CNN: Sowing the seas

At these depths, everything must be done with remote-control robots that install the blowout preventers, submersible pumps and other devices to manage the flow of oil and water on the ocean floor.

FORBES: The delicate art of sucking up

With attacks on non-military targets mounting the UN atrocity followed big attacks on water and oil pipelines in Iraq, and on the Jordanian embassy in Baghdad pressure is rising on America to improve security quickly.

ECONOMIST: Rethinking Iraq | The