1964  Gordon: A7. 15783-PC (field No. U644): Perdido Fm.,
           uppermost 10 ft and probably lower 5 ft of rest Spring
           Shale; 9,000 ft N 88 1/2° E of bench mark 5257 at
           Quartz Spring, near long 117° 29' W., lat. 36°47' N.,
           Cottonwoods Mts., Panamint Range.