Blender Render - Mountainous Object becoming "sketchy"

My Blender Render was working perfectly fine before, then suddenly when i rendered the image it came out all “sketchy”. This is the best way i can explain what it looks like, I’m just wondering how i can fix this problem…Thx

^^^^ The Rendered Image, and the settings used

^^^^ The “World” Settings used

Looks like “Z-fighting” = two identical meshes occupying the same space = two surfaces “fighting” to be on top for the renderer. My guess: The meshes “Plane” and “Plane.001” are identical…