Feature extraction from a map image

Hello, if I have an image like the the one I have attached, how do I use matlab to extract the unique/distinct features in that map image? For the attached image, the image on the far left is the original image and while layers 1, 2 and 3 were extracted from the image on the far left. How do I use matlab to do such separation? Any code will help? Thank you.

[KSSV]

You have not shown the axis limits...Are you sure that for all the images axis limits are same?

[Curious Mind]

Yes the axis are the same