Cross-dating refinement of the Vore Site varves: Little Ice Age climate and cultural adaptations in the northern Black Hills

Abstract

Climatic conditions of the Great Plains and Black Hills region over the past 500 years have been the focus of a number of investigations. These studies have examined a climatic episode known as the Little Ice Age which is generally believed to have been a colder and wetter period than the present. One investigation from the northern Black Hills occurred at the Vore Site (48CK302) where varved sediments were analyzed and determined to show precipitation peaks indicative of the Little Ice Age. Archaeological investigations have tried to establish the relationship between cultural behavior and the changing climate of the Little Ice Age on the Great Plains. Contrasting opinions have resulted in questions on the severity and importance of the Little Ice Age conditions and their affect on prehistoric cultures. In this thesis an attempt is made to acquire high resolution dendroclimatic data to 1) refine the dates of the varved sediments of the Vore Site (48CK302), 2) reconstruct a basic precipitation record of the northern Black Hills, and 3) use the new data coupled with a review of past investigations on the Little Ice Age to examine the severity of the climatic episode for the Black Hills region and its effect on prehistoric cultures. The results have shown that the Vore Site varve sequence is actually discontinuous with gaps in the sequence caused from bison kill episodes or extreme drought. Accounting for the gaps in the varve series yields a date for the entire varve sequence of A.D. 1512-1663. This would date the first five bison kill events at the Vore Site to: A.D. 1553-1558; A.D. 1572; A.D. 1608; A.D. 1637-1642; and A.D. 1663. Analysis of dendroclimatic data for the Black Hills region covering the last 500 years has given relatively inconclusive results in regards to the proposed increase of precipitation during the period. These results, as well as the conclusions of previous investigations suggest that archaeological inquiries must take into account climatic, as well as cultural variables when investigating the Little Ice Age time period in the Black Hills.