This report is a summary of U. S. Geological Survey investigations of the geological effects of the Rainier underground nuclear explosion which was detonated at the Atomic Energy Commission's Nevada Test Site on September 19, 1957. The 1.7 kiloton explosion took place 900 feet below the surface of the ground at the end of a tunnel driven into volcanic tuff of the Oak Spring formation. The rocks close to the explosion point were white to brown pumiceous rhyolitic tuffs that contain phenocrysts of quartz and feldspar biotite and xenoliths of older rocks embedded in a fine-grained matrix of heulandite, clay, ,^-cristobalite, and amorphous material. Unconnected open vesicles make up to 11.5 percent by volume of the rocks. In the natural state these rocks have an average porosity of 24 percent, a bulk density of 2.0, a water content of 14 percent by weight, an acoustic velocity of 8,300 feet per second, a coppressive strength of roughly 4,000 psi at atmospheric pressure, and a tensile strength of roughly 100 psi. Under confining pressures greater than 10,000 psi the tuff will deform at least 20 percent with a consequent increase in density of about 8 percent.Exploration of the rocks disturbed by the explosion has been carried out by one vertical hole and 3 near-horizontal holes and by tunneling toward the point of the explosion. This exploration has revealed a breccia zone extending 70 feet from the explosion chamber. The breccia contains radioactive glass, angular to subrounded blocks, 0.3 to 3 feet across in a
Palaeoenvironmental records from the Northern Plains of North America attest to an extended period of Middle Holocene warming and drying, making this a useful region and period for research on long-term human response to marked climate change. However, archaeological perspectives on human–environment interaction during this episode have remained preoccupied with a refugial model that incorporates limited latitude for dynamic human adaptation. In part, this situation reflects the challenging geomorphological and typological obstacles faced by those studying this period. However, this paper argues that our failure to develop new perspectives also reflects a longstanding and continued conservatism that casts Northern Plains lifeways as inflexible and unchanging, rather than dynamic and adaptable.
Previous research on the Cypress Hills of southeastern Alberta and southwestern Saskatchewan suggests that they have experienced a dynamic history of Holocene landscape change. In particular, the meltwater channels flanking the Cypress Hills appear to have experienced intermittent deposition of sediment transported from upslope alternating with episodes of landscape stability and soil formation. This pattern favours the formation of archeological sites containing multiple stratigraphically discrete occupations, an important characteristic because the geomorphic processes necessary to create such interpretively valuable sites are rare across much of the Northern Plains. Furthermore, the rich resources offered by the Cypress Hills suggest that they were attractive to past human groups, a feature that enhances the prospects for such sites. This paper discusses a study designed to investigate the geomorphic history of the meltwater channels and to identify buried archeological sites in these channels. The preliminary results of this study confirm that the channels have experienced a cyclical pattern of stability and deposition favourable to the stratified burial of cultural remains. Moreover, this study has recovered archeological material from numerous locations, strongly suggesting that the meltwater channels represent an excellent environment for the formation of high-quality sites with multiple discrete cultural layers.
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