Culture and Ecology of Chaco Canyon and the San Juan Basin

90 Chaco Project SynthesisThe second excavated rockshelter, AshislepahShelter, is located on a small, northwest-flowingtributary to Ashislepah Wash. This 70 m long and 8m wide shelter has a fairly flat floor and the openingfaces west. Grasslands and large dune sheets are locatedabove the shelter. Although water can be obtainedby digging into the alluvial wash, there are no nearbypermanent water sources.Excavations at Ashislepah Shelter (Simmons1984c) revealed six stratum and four occupations inarea A. Stratum A, a loose flow sand that was lessthan 5 cm deep, and stratum B, a variable level thatdid not exceed 10 cm of recent organic material (strawand grass) with Pueblo ceramics, as well as pack ratactivity, were thought to represent both a Navajocorral and Pueblo use (late A.D. 1100s to early1200s). In stratum C, which was disturbed byrodents, there was a mixing of materials (straw, grass,ceramics) that made it difficult to separate from itfrom stratum B. Feature 1, a 60 cm long by 10 cmdeep hearth containing carbon and other organicmaterial including com, provided a radiocarbon dateof 1400 ±. 80 (A.D. 550, UGa-4605). Its use wasattributed to early Anasazi or Late Basketmakerpeople. Beneath this, stratumD was approximately 30cm of sterile sandy material that contained coarsegravel lenses that possibly represent roof fall. StratumE was similar to stratum C in that feature 2, a welldefinedhearth, contained charcoal and inorganicremains (com) in its 5 cm thick layer. A radiocarbondate of 2205 ±. 65 BP (255 B.C.; UGa-4606) wasobtained. This was interpreted to represent LateArchaic use. The lowest level, stratum F, was 60 cmthick and similar to stratum D in its sandy matrix.Areas Band C, located south of an inferredNavajo corral, contained some charcoal and recentbone, as well as Anasazi ceramics and nondiagnosticIithics that may be Late Archaic. Simmons (1984c:102) concluded that the stratigraphic context of thesetwo units was equivocal.Survey in the immediate vicinity of AshislepahShelter documented the presence of two Archaic lithicscatters, one that dates to the Armijo phase (1800 to800 B.C.), based on the presence of an Armijo pointlocated directly above the shelter; and a second onethat dates to the San Jose phase (3000 to 1800 B.C.),based on the presence of a San Jose point. Twopossible Archaic sites were also recorded. One is alithic scatter whose age could not be determined; theother is a general debris scatter that included Anasaziceramics along with burnt rock and lithics (Westonand Simmons 1984:116-117).In summary, data from the Chaco SheltersProject suggest that more intensive use of this areabegan around 3,000 B.P. Cultigens from the three excavatedrockshelters include both com and squashduring the Late Archaic-Basketmaker II period.Because the stratigraphy in the excavated rockshelterswas disturbed by pack rats, the recovered data weremore useful for reconstructing past environments thanfor understanding cultural change through time.The San Juan BasinDuring the 1980s, investigators attempted toview data from a regional perspective. In a review ofdata from the San Juan Basin, Judge (1982) indicatedthat major baseline data (e.g. , chronological placementof sites, site distribution within general ecologicalzones, and categorization by site type) were virtuallyabsent in the then-existing database (SJBRUS-thecomputerized database created as part of the San JuanBasin Regional Uranium Study, Wait 1982). Recordingof Preceramic sites was variable; they oftenwere ignored. When recorded, they often werelumped into a single period and were not categorizedby site type. Only 14 (0.2 percent) were attributableto the Paleoindian or transitional; 719 (8.6 percent) tothe Archaic or transitional; and 102 (1.2 percent) tothe Basketmaker or transitional periods. This was atotal of 11.1 percent of all known prehistoric sites(Judge 1982:Table 1.1). Very few were archaeometricallydated; very few studies even attempted toplace them within the Oshara tradition defined byIrwin-Williams (1973), and data that would documentthe Oshara model had not been fully published so thatit was difficult to determine whether the model wastruly applicable to an area broader than the ArroyoCuervo region of the southeast San Juan Basin.Plots of site distributions were presented withcaution. The entire Archaic span could not be subdivided,but preferred locations were in upland dunes.on elevated ridges, and/or on mesas near waterresources. The Basketmaker II period was not clearlydefined, and Judge suspected it was underrepresented.