Northeastern Section - 36th Annual Meeting (March 12-14, 2001)

Analyses of 27 samples collected from the source dike show that the dike is of rhyolitic composition. On the basis of major elements it is similar to other rhyolitic source rocks in SE New England prominently quarried around the Boston basin. However, trace elements readily distinguish the Mt. Jasper dike from these southeastern New England sources. Mt. Jasper material is significantly higher in Nb, Y, Nb/Zr, and Y/Zr, and exhibits distinct ratios of Rb/Sr and Rb/Ba. Eleven samples collected from paleo-workshops at the base of Mt. Jasper are compositionally identical to felsite samples from the dike.

Semi-quantitative, non-destructive analysis of more than 100 archaeological samples from three Paleo-Indian sites (Jefferson, NH, Wells, ME, and Neponset, MA) show that most exhibit similar but not identical trace element concentrations as the dike at Mt. Jasper. The slightly different compositions may indicate: 1) a second nearby source mildly different from Mt. Jasper, or 2) small analytical errors in the non-destructive analytical method. All of these Mt. Jasper-like samples clearly are distinct in composition from southeastern New England sources. Artifacts from an Archaic site in Rumford, ME display a faintly bimodal suite in which some compositions overlap the Mt. Jasper source whereas others are slightly different. The artifact population at the Neponset site is more diverse and representative of at least three distinct sources. Approximately 70% are generally similar to Mt. Jasper material. Twenty percent are identical to the Wamsutta Rhyolite and 10% are similar to the Lynn-Mattapan volcanics, both sources in southeastern New England. Hence, inhabitants of the Neponset site used raw materials from three distinct and spatially separated igneous sources.