Noel solos using notes drawn almost exclusively from basic pentatonic scales. In the first solo he starts with the G major pentatonic scale (G A B D E), as shown here. When the chord progression switches to follow that of the chorus, Noel switches to the E minor pentatonic scale (E G A B D). E minor is the relative minor key to G major and the two scales share the same notes, simply starting on different root notes. Noel uses the same pattern for the second solo, but this time using the A minor pentatonic scale (A C DE G).
E minor pentatonic scale