A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z

(Terms in italics are defined elsewhere in the glossary)

ice cores Borings taken from the Arctic and Antarctic polar ice caps, containing layers of compacted ice useful for reconstructing paleoenvironments and as a method of absolute dating . (Chapter 4)

iconography An important component of cognitive archaeology , this involves the study of artistic representations which usually have an overt religious or ceremonial significance; e.g. individual deities may be distinguished, each with a special characteristic, such as corn with the corn god, or the sun with a sun goddess etc. (Chapter 10)

idealist explanation A form of explanation that lays great stress on the search for insights into the historical circumstances leading up to the event under study in terms primarily of the ideas and motives of the individuals involved. (Chapter 12)

induction A method of reasoning in which one proceeds by generalization from a series of specific observations so as to derive general conclusions ( cf. deduction ) . (Chapter 12) inductively coupled plasma emission spectrometry (ICPS) Based on the same basic principles as OES ( optical emission spectrometry ), but the generation of much higher temperatures reduces problems of interference and produces more accurate results. (Chapter 9)

infrared absorption spectroscopy A technique used in the characterization of raw materials, it has been particularly useful in distinguishing ambers from different sources: the organic compounds in the amber absorb different wavelengths of infrared radiation passed through them. (Chapter 9)

interaction sphere A regional or interregional exchange system, e.g. the Hopewell interaction sphere. (Chapter 9)

isostatic uplift Rise in the level of the land relative to the sea caused by the relaxation of Ice Age conditions. It occurs when the weight of ice is removed as temperatures rise, and the landscape is raised up to form raised beaches . (Chapter 6)

isotopic analysis An important source of information on the reconstruction of prehistoric diets, this technique analyzes the ratios of the principal isotopes preserved in human bone; in effect the method reads the chemical signatures left in the body by different foods. Isotopic analysis is also used in characterization studies. (Chapter 7)