ANTIQUITIES OF THE UPPER GILA AND SALT RIVER 

 VALLEYS IN ARIZONA AND NEW MEXICO 



By Walter Hough 

 GEOGRAPHY AXD PHYSIOGRAPHY 



The area in which are found the archeological remains treated in 

 this bulletin forms part of southwestern New Mexico (western 

 Socorro, Grant, and Luna counties) and southeastern Arizona 

 (Apache, Navajo. Gila, Pinal, Graham, and Cochise counties). It 

 is bounded on the northeast by the great ridge lying between the 

 Gila-Salt and Little Colorado. rivers; on the west and" northwest by 

 the Tonto basin ; on the south by the states of Sonora and Chihuahua, 

 Mexico, and on the southeast by the San Agustin plains. Approxi- 

 mately it extends 170 miles east and west and w 200 miles north and 

 south. Much of this area is covered by the Black Mesa, Mount Gra- 

 ham, and Chiricahua forest reserves in Arizona and the Gila River 

 forest reserve in New T Mexico. (See map, pi. xi.) 



The general region of which this is a large part lies on the south- 

 ern slope of the great diagonal ridge or break* called locally the 

 " Mogollon rim,"" Verde breaks," etc., which extends southeast across 

 Arizona and a portion of New Mexico. This remarkable physio- 

 graphic feature divides Arizona sharply into two regions — the 

 northern, a high plateau drained by the Colorado and Little Colorado 

 rivers, and the southern, a steep slope gradually merging into the 

 level plains along the Mexican boundary, drained by the Gila-Salt 

 river system into the Colorado river, and by the Mimbres, which 

 flows into the inland basin at the foot of the Sierra Madre of 

 Mexico. To the east this ridge takes a northerly direction and is 

 broken into a number of ranges, the Gallo and Datil ranges being the 

 main prolongations that deflect the drainage into the Little Colorado 

 on the north, the Gila on the south, and the Rio Grande on the east. 



The Gila-Salt and their affluents rise in the sinuous " rim," which 

 ordinarily presents at its upper portion enormous inaccessible cliffs 

 gashed by innumerable rugged canyons. The high mountains cause 

 precipitation and act as storage reservoirs. Here springs burst forth 

 and trout streams take their rise. Many rivulets trickle from the 

 heights of the great break, coalesce, and descend precipitously. between 



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