What is the floor of Class E airspace within a shaded magenta area?

In a shaded magenta area on a sectional aeronautical chart, the floor of Class E airspace is typically set at 700 feet above ground level (AGL). This specific indication is a part of the depiction of Class E airspace, which extends from a certain altitude up to the base of the overlying airspace and allows for both visual and instrument flight rules operations.

The shading signifies that the transition from Class G (uncontrolled) airspace to Class E (controlled) airspace begins at this altitude, providing additional structure and guidelines for aircraft operating in this airspace. Understanding this boundary is crucial for pilots in ensuring they are operating within the correct regulatory framework for airspace, especially when transitioning between unregulated and regulated environments during flight operations.

Other altitude thresholds indicated by different types of airspace markings do not apply in this context, thus reinforcing the importance of understanding chart symbology for navigation and safety.