Figure 13. Photographs showing breccias in the Caetano caldera. (A) Approximately 10-m-thick mesobreccia lens in lower unit of Caetano Tuff near south margin of caldera just north of Red Mountain. Mesobreccia composed of angular fragments (up to 50 cm) of Paleozoic quartzite, argillite, and chert, Tertiary andesite, and white pumice in matrix of finely ground Paleozoic rocks. Hammer is 46 cm long. (B) Interbedded coarse, clast-supported mesobreccia and lithic-rich Caetano Tuff near south margin of caldera north of Red Mountain. Blocks are mostly Paleozoic quartzite and argillite and locally reach 2 m in diameter. Hammer is 46 cm long. (C) Brecciated Paleozoic quartzite block in mesobreccia at Wilson Pass. Hammer is 55 cm long. (D) Large block of brecciated Paleozoic chert enclosed in Caetano Tuff near base of upper unit 0.5 km north of Tub Spring. Block is 5 m in maximum dimension and is 4 km from the nearest exposed caldera margin.