PCAS General Meetings

Monthly lecture meetings feature noted archaeologists and anthropologists who provide insight into a variety of topics. Lecture meetings are held at the Irvine Ranch Water District Community Room, 15500 Sand Canyon Avenue (between the I-5 and I-405) in Irvine, on the second Thursday of each month, at 7:30 pm. Meetings are free and open to the public. See vicinity and detail maps of PCAS meeting location. For additional directions, please call Scott Findlay, 714-342-2534.

Please Note: The Irvine Ranch Water District neither supports nor endorses the cause nor activities of organizations which use the district’s meeting rooms that are made available as a public service.

You are invited to join the speaker and PCAS members for dinner before the general meeting. It's an informal opportunity to visit with an acknowledged expert. We meet at 6:00 pm at a local restaurant. Please check the newsletter (left menu) for location.

Schedule and Speakers

Please note that last minute changes may occur.

No meetings in July and August


September 14, 2017

Dr. Michael J. Moratto

People of the Restless Inland Sea: Human Adaptations to Ancient Lake Cahuilla


Manual excavation of Unit EXU 107 in sand dunes at CA-RIV-6896/6897.

Any consideration of late prehistoric land-use and settlement patterns in the Coachella Valley and beyond must recognize that ancient Lake Cahuilla is the elephant in the room. The fluctuations of that great body of water, and the multitude of biotic resources that accompanied it, exerted a profound influence on where people lived, how long they could stay, their particular subsistence activities, and when they had to relocate. As the lake was filling, people depending on its bounty needed to move to higher ground whenever so dictated by the rising waters. Conversely, as the lake fell, economic efficiency required people to follow the retreating shoreline. This meant that a high degree of mobility, not to mention cultural flexibility, was required of those who relied on the resources bestowed by this vast “inland sea”.

It is not surprising, therefore, that prehistoric land-use and settlement practices along the north shore of Lake Cahuilla (in what is now Indio) were correlated with the rising or falling, presence or absence, of the lake.  Both the fluctuations of water levels and human responses to ever-changing conditions have been the subjects of a multi-year (2002-2017) program of archaeological investigations at site CA-RIV-6896/6897 by Applied EarthWorks, Inc., and much of this research was directed by Michael Moratto. Six high stands of Lake Cahuilla during the past 1,300 years have been identified, and radiocarbon age determinations associated with cultural features have confirmed a strong correlation between human activities at the site and high stands of the lake. These and related topics will be explored in Dr. Moratto’s presentation.


Dr. Michael J. Moratto (RPA; Principal Archaeologist, Applied EarthWorks, Inc.) has directed hundreds of anthropological projects in the western US. Among his interests are peopling the New World, the American West, cultural ecology, California anthropology, and linguistic prehistory. A retired university professor, he is a Fellow of the California Academy of Sciences and past president of local, statewide, and national professional societies. He has also served on the State Historical Resources Commission. Of 200+ publications, Dr. Moratto’s California Archaeology (1984, 2004) is perhaps best known. He has received many honors and awards from professional societies, universities, governmental agencies, and civic organizations.


October 12, 2017

Dr. Alan P.  Gold

Ghost Dance Rock Art


November 9, 2017

Dr. Janine Gasco

Cacao (Chocolate) in Precolumbian and Contemporary Mesoamerica


December 14, 2017

Dr. Dennis L. Jenkins

Paisley Caves