Deep ocean core studies have lead to the identification of Marine Isotope Stages MIS which can be dated astronomically. Google Scholar Ferguson, C. Thames and Hudson,pp. Michels, Joseph W. Studies of Mexican, Guatemalan, and Sardinian obsidians by Michels and his colleagues are critiqued. This discussion focuses attention on the applications of the radiocarbon, dendrochronology, obsidian hydration, and archaeomagnetic sex Kerala in historic preservation. Maddin, L. Chronometric Dating in Archaeology is well organized, clearly written, and contains the most up-to-date information in archaeology dating science Aitken 1990 based on a dozen dynamic topics.