русский
ледяное сало испанский
hielo graso 
Thin, soupy layer of frazil crystals clumped together, which makes the ocean surface resemble an oil slick.
1
It was enough to make him take a step onto the colorless grease ice beyond.
2
In the open water, grease ice is forming.
3
Its shore was gray with grease ice, yet its center was black, oily, and steaming with frost smoke.
4
With the shields activated on the bottoms of his boots, it felt like he was skating on greased ice.