PREFACE

The overall excavation strategy for open sites is based on the general model of site structure discussed inChapter 4. Open sites are expected to be the remnants of camps occupied by residential groups or taskgroups, both of which may be associated with specialized processing facilities (e.g., ring midden/burnedrock middens and bedrock mortars), or the remnants of limited activity areas (e.g., lithicprocurement/workshop areas and hunting stands) that may also have associated camp components. Ineither case, the sites are expected to consist of one or more activity areas. Most often, those activity areaswill be centered on some type of feature. Minimally they should be evident from the artifact distribution,which is expected to reflect refuse disposal patterns, although this patterning may be partially obscured byoverlapping occupations at sites that were utilized repeatedly and by the effects of post-occupationalerosion and pedo-turbation processes.One implication of this general model is that excavations are most productively focused in the generalarea of features and artifact concentrations. Although obvious to any archaeologist, this observation hasimplications for the regional sampling design that are not as apparent. We have argued previously thatsites are the basic sampling units and that the sites included in the sample need to be fully excavated inorder to achieve the objectives of the research design. Implicit in this argument is the assumption that theboundaries defined for sites on survey generally correspond to artifact concentrations and/or featureclusters; that is, to the areas most intensively used or occupied by prehistoric groups. Review of thesurvey records suggests that this assumption is incorrect for many of the larger open sites identified insoutheastern New Mexico, however. As mapped during survey, many of those sites encompass severalwidely spaced artifact concentrations and/or feature clusters, often with little or no cultural material in theintervening areas. In dunes, the concentrations may be exposed in several adjacent blowouts, while theblowouts between clusters are devoid of cultural materials. At these large sites, the artifact/featureclusters rather than the site are the logical units of study. Consequently, those clusters should be treatedas separate sites in selecting the data recovery sample.The general site structure model also has implications for the scale of the excavations. For features, anyartifacts are expected to exhibit a drop zone-toss zone discard pattern, so excavation of an area extendingat least 2-3 m from the feature would be necessary to recover discarded artifacts and food refuseassociated with the use of that facility. A larger area would have to be cleared to locate structures orsleeping areas that might be associated with hearths marking food preparation areas. Further expansion ofthe excavation would be needed to locate any other households occupying the camp, and activity areasand refuse deposits on the periphery of the living space. For hunter-gatherers in semi-tropicalenvironments, camp size is reported as 44–531 sq m for the Efe (Fisher and Strickland 1991), 550–1,250sq m for the Hadza (O’Connell et al. 1991), 175–896 sq m for the !Kung, and 9,496–152,776 sq m for theWestern Aborigine (Gould and Yellen 1987). As the Aborigine camps are semi-permanent settlementsnear homesteads or on government preserves, their size is probably outside the range for prehistoriccamps in southeastern New Mexico, although possibly not for some repeatedly occupied locales. Thefigures for the other groups, however, are relatively consistent and suggest that an area of 500–1000 sq mshould be excavated in investigating residential sites.Surface SitesAs defined here, surface sites are sites on old erosion surfaces mantled by shallow (0–30 cm)accumulations of more recent sediments. There appear to be two general processes through which thesekinds of sites were formed. The first is that materials at the site were originally deposited in deepersediments covering the erosion surface that were subsequently worn away. Sites formed by this processare therefore secondary deposits, potentially consisting of materials from multiple occupation episodes ofvarying age. It seems unlikely that datable materials and subsistence remains would be preserved at thesesites but, where wind was the dominant erosive agent, elements of the site structure may be discernable.6-5