What are these strips on the surface of Mars?

The robot Opportunity, on the surface of the "red planet" has made a very important discovery, as well as exploring Mars, "stumbled" over the elongated formations you see in the picture.
The formations are reminiscent of striping the lanes on city streets!
The first estimates of researchers at NASA, talking about a high probability it is plaster, which if confirmed would be the strongest evidence since the discovery of water on Mars