But I am still confused about the meaning of "land...on slippery slick"Slippery means, um, slippery, which oil can be. Slick is an oil slick (noun) ... which is why it's used in a headline about oil.
Editors spend a great deal of time coming up with clever, and sometimes self-indulgent, headlines. They are not written by the person who writes the story.
I see. Copyright, thank you for your vivid explanation!Imagine standing on one spot and then taking a jump to a spot four feet away (we'll make it easy). When your feet come back to earth again after your jump, you can be said to land (like an airplane). We even talk about people landing on their feet (rather than falling to the ground) after a setback or unexpected occurrence.
Now imagine that when you landed, you didn't land on dry ground, but on a slippery slick of oil poured on a marble floor. There's every chance you'd lose your balance. That's what's happening with the major oil producers. They've landed unexpectedly on/in a spot where it's difficult to maintain their balance.