Oblique aerial photograph of El Capitan and the southern end of the Guadalupe
Mountains. Note the gentle regional east-
northeast tilt of all strata due to Tertiary uplift and the lateral transition from massive (largely dolomitized), steeply
dipping Capitan reef-talus at top center to nearly flat-lying Delaware Mountain Group clastics to the right (toward the
former Delaware basin). Those clastics also underlie the carbonate cliffs of El Capitan, demonstrating progradation
of the Capitan shelf margin over older, flat-lying beds of basinal Brushy Canyon Fm. sandstones. Photo from King
(1948, plate 1).