The Magenta shading points out the "E" airspace drops to 700 feet above the ground, rather than the 1200 feet adjacent to it. The Magenta shading can be assumed to continue across the map, until it meets another Magenta line. On older VFR sectional maps, there used to be a blue shaded area adjacent to and touching the magenta shading going in the other direction. This deplicted 1200 feet. You could also assume the blue shading continued across the map until it contacted another blue shading, or another type airspace marking. Because it was always assumed that the blue lines butted up against Magenta lines, and that E airspace started at 1200 feet, unless shown different (magenta lines for one), the blue shading was removed from the charts. So, assume there is now that grey shading against all magenta lines. Now, we have that grey line (used to be blue), showing 1200 feet around all airports just outside the magenta line, but just not there because it is assumed. However, the specific spot you are talking about 'is' different. E airspace does not go over that sliver of land between the grey lines. At the grey line right west of Page, the E airspace is 1200 feet. Right at the darkest part of the first grey line, the E airspace goes vertical to the next airspace above it (in this case to 14,500 feet). Then, between the two grey lines, you have G airspace from the ground up to 14,500 feet! You can also see this same airspace marked around Prescott. Away from the dark grey line is 1200 feet floor of E airspace, and inside it the G airspace goes vertical from the ground to the next airspace above. I don't think you will find any of this G airspace from the surface to 14,500 feet east of the Rockies. A trivia question: Can you fly IFR in this airspace (G), between the dark grey lines, say at 9000 feet, in the clouds, without a IFR Clearance, or talking to Center on a radio?
Good questions!
Jim Baker
CFI-IA
RV-6