The Ground Slate Transition on the Northwest Coast: Establishing a Chronological Framework

摘要

This thesis establishes the earliest appearance of ground slate points at 50 locations throughout the Northwest Coast of North America. Ground slate points are a tool common among maritime hunter-gatherers, but rare among hunter-gatherers who utilize terrestrial subsistence strategies; ground slate points are considered one of the archaeological hallmarks of mid-to-late Holocene Northwest Coast peoples. The appearance of ground slate points in the archaeological record is frequently marked by a concurrent decline in the prevalence of flaked stone points, a phenomenon often referred to as u22the ground slate transition.u22 Until now, the specific timing of the appearance of these tools has been ill-defined, and a number of competing theories have arisen to explain the apparent preference for ground slate points over flaked points by prehistoric peoples. By drawing upon a sample of 94 artifact assemblages from 50 sites in Alaska, British Columbia, and Washington, I have constructed a database of artifacts counts, provenience information, and radiocarbon dates which allows for inter-site comparisons of the earliest appearance of the technology. My research has identified a general north to south trend in the appearance of slate points; which begin to appear in the archaeological record around 6,300 cal BP in southeast Alaska, to 2,900 cal BP in Puget Sound. There are notable exceptions to this pattern, however. Given that these data are drawn from both cultural resource management reports and academic literature, I have qualified these findings by addressing some of the common problems of making inter-site comparisons, such as the comparability of radiometric dates, which I address by undertaking a radiocarbon hygiene program. The chronology constructed here provides an important tool for evaluating theories about the ground slate transition, and thereby aiding in untangling the link between aquatic subsistence strategies and technological decision making.