Fig. 29 — Cotahuasi on the floor of the Cotahuasi canyon. The even skyline of the 

 background is on a rather even-topped lava plateau. I he terrace on the left of the 

 town is formed on limestone, which is overlain by lava flows. A thick deposit of ter- 

 raced alluvium may be seen on the valley floor, and it is on one of the lower terraces 

 that the city of Cotahuasi stands. The higher terraces are in many cases too dry for 

 cultivation. The canyon is nearly 7,000 feet (2,130 m.) deep and has been cut through 

 one hundred principal lava flows. 



