Archaeologist Matthew Pailes will give a presentation to the Santa Cruz Valley Chapter of the Arizona Archaeological Society on Nov. 12 at 7 p.m. at the North County Facility at 50 Bridge Road in Tubac.

His topic will be cerros de trincheras (“entrenched mountains”), a specialized type of Hohokam village found in the Santa Cruz River basin, starting about AD 1300. The presentation is free and open to the public.

Cerros de trincheras are village sites built on volcanic hills. These hills usually have numerous masonry terraces on their slopes and structures on their summits. They are found across the southern Southwest of the United States, as well as in northwest Mexico. This presentation will discuss a number of theories for why this style of village developed and how Hohokam communities were organized during this time. The Hohokam, the ancient people of Southern Arizona, flourished in this area for 1,000 years before the arrival of Europeans and are often considered the ancestors of Southern Arizona’s O’odham peoples.

Pailes, currently a preservation archaeologist at the Center for Desert Archaeology in Tucson, has written on the cerros phenomenon in graduate work at the University of Arizona and is currently modeling Hohokam cultivation strategies in the southern Tucson basin.

The Santa Cruz Valley AAS chapter meets the second Thursday of each month. In addition to hosting programs featuring experts in historical and archaeological topics that focus on the Santa Cruz River Valley, the chapter offers members opportunities for assisting archaeologists with excavating area sites, hikes, and tours to archaeologically and historically significant locations. The chapter’s educational and advocacy programs are intended to preserve and protect the region’s unique cultural resources and draw upon and partner with other organizations with heritage-based goals and objectives. Santa Cruz Valley AAS chapter members also have the opportunity to participate in many educational, stewardship and excavation activities of the statewide organization’s other local chapters.

For more information about the Santa Cruz Valley AAS Chapter and its activities, call Alan Sorkowitz at (520) 207-7151 or inquire via e-mail at asorko@cox.net. The Arizona Archaeological Society Web site at www.AzArchSoc.org offers information about the Santa Cruz Valley chapter and others throughout the state, as well as activities and benefits of membership in the statewide organization.