A Revised Research Context for the Prehistoric Archaeology of the Little Boulder Basin Area, North-Central Nevada

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Barrick Goldstrike Mines, Inc., (BGMI) as part of its ongoing efforts to manage cultural resources within its area of operations, has contracted SWCA Environmental Consultants to prepare this research context for the prehistoric archaeology of the Little Boulder Basin (LBB) and the surrounding area along a portion of the Carlin Trend in north-central Nevada. BGMI is supporting the preparation of this document at the request of and in consultation with the Bureau of Land Management, Elko District, Tuscarora Field Office (BLM-Elko). The purpose of this document is to assist BLM-Elko with its responsibilities under Section 106 of the National Historic Preservation Act by 1) synthesizing the extensive archaeological research that has been conducted in this part of the Great Basin over the past 25 or so years; 2) using the results of this synthesis to develop a comprehensive approach for evaluating, or re-evaluating, whether prehistoric archaeological sites in the area are eligible for the National Register of Historic Places (NRHP) under Criterion D; and 3) providing a basis for research designs to be implemented in any archaeological mitigation work that may be required in the future.

This document is proposed as an update of and a replacement for a historic context that was prepared for the LBB area in 1991. Due to the considerable amount of work that has taken place since it was written, some of the research questions outlined in the 1991 historic context have been answered, some have required revision, and new questions have arisen. Consequently, it is appropriate to reconsider NRHP eligibility determinations made under the 1991 historic context based on updated research priorities for the area. Defining a new set of research priorities for the LBB and surrounding area is the major purpose of this document.

The new research priorities developed in this document are based on a synthesis of the results of archaeological excavations conducted to date in the LBB and surrounding area and an evaluation of the current status of archaeological knowledge about the area. Over 50 sites in the area have been excavated. However, a comprehensive treatment of the knowledge gained through these excavations has never been produced; several separate reports describe excavations at individual sites or small groups of sites, but the bigger picture that might be painted by the cumulative information obtained from these sites has remained unclear. This document fills that gap by compiling the data from all excavated sites in the vicinity of the LBB and by applying the collective dataset to research questions from the 1991 historic context. The main substantive results of this research synthesis are as follows.

The distribution of radiocarbon dates from archaeological sites in the area suggests that sustained human occupation began around 1200 B.C. and continued without major interruption through the period of Euro-American settlement. Projectile points further provide evidence for at least sporadic use of the area prior to 1200 B.C. The lack of radiocarbon dates from before this time, and the more general paucity of evidence for substantial occupation prior to 1200 B.C., may be due to insufficient preservation of earlier materials and/or insufficient testing of deeply buried deposits, but at face value, the available data suggest that humans used the area only lightly until well into the late Holocene. Based on a synthesis of available chronological data, a slightly revised phase sequence for the area is presented. Revisions to the projectile point and obsidian hydration chronologies that have been used in the area are also suggested.

It has previously been well established that multicomponent deposits (i.e., deposits containing material from multiple time periods) are very common in the LBB area, and much work has focused on attempting to more successfully limit excavation efforts to single-component deposits, which enable change over time to be examined. Employing an explicit and consistent set of criteria for identifying assemblages as single-component, only a small proportion of the previously excavated assemblages from the study area— no more than about a third—can be identified as such. Geoarchaeological work that has been conducted suggests that, in most LBB area geomorphological settings, archaeological deposits are likely to be shallow and to lack stratigraphic distinctions, a fact that likely goes a long way towards explaining the prevalence of multicomponent archaeological assemblages in the area. Another major reason why many previously excavated LBB area sites and site loci cannot be identified as single-component is that they lack sufficient dating information for evaluating their occupational history.

An analysis of potential predictor variables shows that there are no clear-cut ways to determine whether a site or site locus is single-component prior to excavation based either on environmental variables or on characteristics of surface archaeological assemblages. It is demonstrably not the case that sites or site loci with larger or denser surface artifact assemblages are more likely to be multicomponent, as some have previously suggested may be the case. On the other hand, the number of archaeological features found at a site or site locus does appear to substantially improve the ability to identify deposits as single-component, likely because features typically provide abundant dating information in the form of radiocarbon dates and associated artifacts. The most productive approach to identifying single-component deposits may therefore be simply to focus on locating archaeological features, and there fortunately are some variables that do seem to be able to predict whether a site or site locus will contain archaeological features. In particular, the presence of ground stone artifacts and/or ceramics, as well as site location in upland settings, appear to be indicative of the presence of features with better than random chances.

Turning to issues of subsistence, comprehensive analyses of faunal and floral remains from the LBB area support the previously made argument that large mammal encounter rates declined around A.D. 1300, leading to a reduction in overall foraging efficiency and an expansion of diet breadth. However, a new result also emerges from these analyses, which is that, prior to approximately A.D. 700, diets appear to have been about as broad, and foraging efficiency about as low, as was the case after A.D. 1300. Thus, the period between A.D. 700 and A.D. 1300 stands out in terms of diet breadth and foraging efficiency in comparison to both earlier and later times. An analysis of ground stone tools from the LBB area indicates greater investment in milling technology both before A.D. 700 and after A.D. 1300, a pattern that is consistent with the argument that has been previously made that people adjusted their investment in various forms of technology in response to changes in resource selection and foraging efficiency. Ceramic data from the LBB area also seem to be consistent with such a change in technological investment in that pottery from the area appears to date primarily after A.D. 1300 and may be associated with increased use of seeds at around this time; however, the fact that LBB area ceramics are only loosely dated presently limits the degree of confidence that can be placed in this conclusion. Finally, the frequency of small hearth features that lack rocks, relative to larger features with rocks, increases at around A.D. 1300, perhaps further indicating increased investment in technologies used to handle low-return resources.

A consideration of site structure and function leads to several important insights into settlement and mobility in the LBB area. For one, all sites, from all time periods, appear to represent the remains left by small groups of highly mobile hunters and gatherers who occupied sites for short periods of time. Overall, site structure is extremely simple. No residential structures have been identified on any sites of any time period in the LBB area, numbers of other types of features on sites are generally low and the features are relatively simple, and no secondary refuse areas have been identified. Variation among sites in potential indicators of site function is slight and centers on differences in densities of artifacts and faunal material. Although most sites are likely best characterized as small, generalized camps, two other site types may be present. One type, which is characterized by high densities of debitage and tools, may represent areas where stone tool production and repair were a particular focus. The second, which is characterized by higher densities of ground stone and high faunal richness, may represent areas where food collection and processing were emphasized to a relatively greater degree. It is notable that the distribution of these site types is not as patterned spatially as might be expected. General camps and tool processing sites appear to be located across a variety of settings, distances to water, and vegetation zones. Importantly, though, food processing sites appear restricted to particular ridge tops and the big sagebrush vegetation zone. Regarding temporal variation, the distinction between tool production and food processing sites seems to be clearest prior to A.D. 1300. This suggests that site functions may have been more varied before this time, whereas after this time use of the LBB area may have been much more homogenous.

Chipped stone artifacts comprise by far the most substantial portion of the LBB area archaeological record. A variety of analyses of such artifacts are presented in this document, and based on the cumulative results of these, in conjunction with the insights provided by the site structure and function analysis, a model of chipped stone assemblage variability and mobility is proposed. Chipped stone assemblages associated with pre–A.D. 700 occupations in the LBB area appear to represent debris from populations with a large annual range who were highly residentially mobile. Obsidian sourcing data indicate that they had access to sources from a large area. In addition, raw material selection favored high quality chert from the relatively close Tosawihi Quarries and the production of bifaces, as might be expected for groups with high levels of mobility. Between A.D. 700 and A.D. 1300, chipped stone assemblages, and undoubtedly the underlying mobility and economic strategies, changed radically. Data from obsidian sourcing indicates a great reduction in range size. Furthermore, use of non-Tosawihi materials increased, also suggesting a constriction in annual range requiring greater reliance on local materials. The frequency of residential moves, however, appears to have remained high, albeit within a greatly reduced range. After A.D. 1300, it appears that mobility patterns changed again. Evidence of obsidian procurement indicates that the overall foraging range was the greatest during this period. In addition, an increased investment in producing later-stage bifaces at the Tosawihi Quarries indicates that populations either expected to travel long distances or to be away from the quarry for long periods of time. The relative abundance of Tosawihi chert is highest after A.D. 1300, and it may be that the LBB area after this time was used only as a stopping point on trips between the Tosawihi Quarries and points to the south.

There are remarkable parallels between temporal patterns in subsistence-related data and temporal patterns in chipped stone data. Simply put, the period between about A.D. 700 and A.D. 1300 stands out in relation to both earlier and later times in exhibiting evidence for higher foraging efficiency and correspondingly narrower diets, as well as evidence for a greatly reduced overall range size. The explanation for the patterns in foraging efficiency and diet breadth that currently seems best supported is that favorable climatic conditions for artiodactyl prey between A.D. 700 and 1300 enabled higher foraging efficiency for human predators, which, in turn, predictably led to relatively narrow diet breadth, as well as associated changes in subsistence-related technologies. The reduced foraging ranges that people evidently traversed during this period may also be predictably related to climatic variability in one of several ways. First, it is possible that, if human population densities throughout the Upper Humboldt region were highest between A.D. 700 and 1300—something that may have resulted, at least in part, from the higher effective precipitation that characterized this span of time—then foraging ranges may have been somewhat constricted due to demographic packing. Another possibility is that climatic variability led to changes in the costs and benefits of residential mobility. Specifically, the higher foraging returns that hunter-gatherers in the LBB area were evidently able to obtain between A.D. 700 and 1300 may have made it economical to move residentially less often. Further evaluating such "big picture" hypotheses for major adaptive shifts in LBB area prehistory would be a very worthwhile goal for the next generation of archaeological research in the region.

Based on the just-described research results, an extensive series of research questions and data needs is proposed to guide future archaeological investigations in the LBB area. Many of these research questions would likely best be answered using either existing data from previously excavated sites or data from outside the LBB area. However, many can also be answered using data from as-of-yet unexcavated sites within the LBB area. The specific characteristics, or "eligibility factors", that would enable an LBB area site to provide data applicable to research questions outlined in this document, thereby making that site eligible for the NRHP under Criterion D, are described. It is also suggested that research potential be evaluated at the level of the intra-site locus or artifact concentration, rather than at the level of the site as a whole, and that loci or concentrations with high research potential be considered to be components that contribute to the eligibility of NRHP-eligible sites. Finally, a range of further management recommendations are made, covering issues such as strategies for mitigating adverse effects to NRHP-eligible sites, opportunities for academic research in the area, data submission and curation standards, and guidelines for future updates of this research context.

Publication Date

Fri, 12/15/2017

Region

National Office

Organization

Collection: BLM Library
Category: Cultural Resource Series

Keywords

Cultural-Heritage-and-Paleontology