New insights about the construction and use of shell mounds from the geochemical analysis of mollusks: an example from the greater San Francisco Bay

Abstract

A new method developed by Schweikhardt et al. (2011) for the geochemical analysis of bay mussels is applicable (when combined with radiocarbon assessments) for examining the seasonal construction patterns and growth cycles of coastal mound sites over time. Ideally suited for the analysis of mollusk fragments in museum collections, this method allows archaeologists to evaluate divergent models about the functions of mound sites, as well as the mobility practices and social organizations of the mound builders. In this case study, the method is employed to examine two adjacent mounds (Ellis Landing, Brooks Island) in the San Francisco Bay Area, California to assess whether their occupants may have participated in a broader multi-site community dating to the Late Period (1100–250 BP).