A study by Hereford, R. (2002) supports the environmental stress theory. He found that periods of increase arroyo cutting coincide with periods of high climatic variation.


According to the figure above Arroyo cutting occurred between A.D. 1200 and 1400 coincides with the drought period mention by Larson and Michaelson (1990) and Larson el al (1996).

Hereford, R. (2002) said that erosion and aggradation resulted from climate variation. He also points out that the cutting may be related to the change between Medieval Warm and Little Ice Age.

Home
Location
History
Mystery
           Environmenatl stress
           Collapse of an economic trade system
           Warfare
           Religion crisis
References