I will answer your questions. I do not want anymore question on this subject. I will take me all day to try and find the ones I did not.

Maksutov

1. OK, it's a false color image of a part of the surface of Mars.

The image is on Meridiani Mars taken by Opputonity Rover sol 80.

2. As you said it's a false color image. What's the problem? Are you mistaking the blue tints for water?

I said it was false color because it is. True color is an opinion. The blue tint is nothing to do with water. The water in the bottom of the trench is less blue than the surface material in that filter set.

I think that is it for you.