Tin Mining and Sediment Supply to the Ringarooma River,Tasmania, 1875–1979

Tin mining, based largely on alluvial tin deposited along the line of the ancestral Ringarooma, began in 1875 and reached a peak in the period 1905-9. Output declined thereafter and, following a brief recovery during the Second World War, had virtually ceased by 1981. Neither the methods, location nor level of production remained constant during the mining era. The widespread use of hydraulic sluicing and the proximity of many mines to the main river were major factors contributing to the high rate of sediment supply, with the Briseis mine at Derby being the dominant source. Based on data from published and unpublished papers, and mine records, the variable nature of that supply was estimated using a procedure which takes account of the effects of storage and changing practices. Many input points supplied material but the overall pattern is one in which downstream reaches made later starts and reached later peaks, suggesting that they will continue to experience the effects of an increased sediment load for some time.     

The logic of the herd: A computer simulation of archaeological herd structure

The advent of new techniques of dental ageing has permitted inferences about the age-structures of ancient animal populations on the basis of faunal remains. Unfortunately, inference from archaeological populations of faunal elements to the age-structure of ancient herds is fraught with both sampling problems and logical difficulties. The relationship between a living herd—a dynamic system characterized by growth—and a static archaeological population is more complex than that assumed by current models based on kill-off patterns and survivorship curves. Using a computer simulation, these logical relationships are explored, and the effects of herd growth on the composition of live and death populations are evaluated. By employing the simulation within a deductive framework, constrained by ethnographically derived criteria for reproduction, mortality, and economic viability in the Near East, it is possible to determine whether certain archaeological kill-off patterns could represent viable herding systems. Examples were found to vary widely in terms of both demographic plausibility and economic viability. Some implications for the possible course of ova-caprine domestication in the Near East are discussed.     

PREHISTORIC FLINT MINES AND THEIR IDENTIFICATION AS SOURCES OF RAW MATERIAL

This paper is a statistical and geological study of the results of analysis of flint from British and West European flint mines, carried out by emission and atomic absorption spectroscopy. Groups of flint specimens were studied from each geographically separate flint mining area. Flints were analysed for a group of easily measured trace elements shown by previous work to be generally present. The ratios between the trace elements form a consistent pattern for each flint mine and statistically valid differences of pattern can be recognized between different flint mines. A geological investigation shows that the measured trace elements may be derived from clay minerals and explains geographical and statistical variation in the composition of flint in terms of its mode of origin in the chalk. An advanced statistical technique allows individual flint specimens of unknown origin to be attributed by their composition to one or other of the identified flint sources. The archaeological implications of this study are discussed.