Sea-rafted pumice on the Australian east coast: numerical classification and stratigraphy

Sixteen elements (Ca, K, Mg, Na, Al, Fe, Mn, P, Co, Cu, Li, Ni, Rb, Sr. Ti, Zn, determined by atomic absorption) were identified in 453 pumice fragmen ts recovered from Holocene strandplains in southeast Queensland and New Sou th Wales. Eight pumice groups and 13 subgroups are recognised by numerical analysis. Some pumices record known eruptions. Others come from known centr es in Tonga and Vanuatu. Several pumice eruptions have occurred from some c entres, but there are instances of single episodes. The numerical analyses, combined with carbon dating and soil identification, identify marker horiz ons in the development of the strandplans. These horizons provide a time-sc ale for soil development. Pumice that occurs in middens has an archaeologic al value. Coke was found with recent pumice. It conveniently identifies the modern industrial age.