Specify your area of interest by selecting the 'floater' pin and dropping it on the map.   Drag and drop the pin to move around the map, and change the radius setting to give you more or less coverage.

 

Actually, there are three ways of defining your area of interest.  In addition to the pin, you can define a well or rig as your centre of interest simply by selecting it with the click of the mouse.  The Floater pin gives you the advantage of moving to different regions of the map quickly and effortlessly to look for spudable wells and rigs.