One on the left is a colour gradient contour map of subsurface geological rock layers where blue is the shallower. Thats the 2D representation of one layer visible in the 3D model. So what you are seeing here is actually an ancient reef structure that was drilled into years ago for oil production. It's ripe for some horizontal wells placed within the producing zones to extract more of the oil in place. Due to oil being lower density than water, both of which are present in rocks, one looks for structures like this with a non permeable rock above one with porosity. The oil will then build up and accumulate within the structure and be trapped, creating a reservoir