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The Halibee member of the Upper Dawaitoli Formation of Ethiopia's Middle Awash study area features a wealth of Middle and Later Stone Age (MSA and LSA) paleoanthropological resources in a succession of Pleistocene sediments. We introduce these artifacts and fossils, and determine their chronostratigraphic placement via a combination of established radioisotopic methods and a recently developed dating method applied to ostrich eggshell (OES). We apply the recently developed 230Th/U burial dating of OES to bridge the temporal gap between radiocarbon (14C) and 40Ar/39Ar ages for the MSA and provide 14C ages to constrain the younger LSA archaeology and fauna to ∼24 to 21.4 ka. Paired 14C and 230Th/U burial ages of OES agree at ∼31 ka for an older LSA locality, validating the newer method, and in turn supporting its application to stratigraphically underlying MSA occurrences previously constrained only by a maximum 40Ar/39Ar age. Associated fauna, flora, and Homo sapiens fossils are thereby now fixed between 106 ± 20 ka and 96.4 ± 1.6 ka (all errors 2σ). Additional 40Ar/39 results on an underlying tuff refine its age to 158.1 ± 11.0 ka, providing a more precise minimum age for MSA lithic artifacts, fauna, and H. sapiens fossils recovered ∼9 m below it. These results demonstrate how chronological control can be obtained in tectonically active and stratigraphically complex settings to precisely calibrate crucial evidence of technological, environmental, and evolutionary changes during the African Middle and Late Pleistocene.

The analysis here of 62 powdered soil samples indicates considerable variability based on the EDXRF analysis. I leave the interpretive details to you.

The artifacts were produced with Sauceda Mountains obsidian (n=2) with one from Los Vidrios,not unlike the distribution of sources in previous studies at CPWR (Table 1 and Figure 1).

The analysis here of sevenpowdered samples indicates a variable composition(Table 1). The plutonicrocks vary from mafic to silicic(Table1).

All the artifacts were produced from two of the sources in the Mule Creek Obsidian Complex, Mogollon-Datil volcanic province, western New Mexico (Antelope Creek and Mule Mountains), although obsidian from these sources are also available as secondary deposits in San Francisco and Gila River Quaternary alluvium in eastern Arizona (Shackley 1992. 1998; Shackley et al. 2018; Table 1, Figure 1, and cover image herein). The cortex on sample #12 fnmLA 187467 appears to be typical of the secondary deposit obsidian in Gila River alluvium (Shackley 1992,1998).

The Newman Dome pyroxene dacite dome complex in the Taos Plateau Volcanic Field is a prominent stone tool raw material that was used for stone tool production for at least 11,000 years throughout northern New Mexico and southern Colorado, and perhaps beyond(Boyer 2010; Newman and Nielsen 1987; Shackley 2011a; Vierra 2010; Figures1 and 2 herein). The analysis here of 24 source samples is an extension of the earlier study (Shackley 2011a) and indicates that this extensive dacite dome complex is compositionally homogeneous in trace elements at least in the northern and central portion of the dome complex

The analysis here of 21 obsidian cruciforms, and one cruciform produced from a volcanic or plutonic rock, from archaeological sites presumably from southern New Mexico and northern Chihuahua indicates a diverse provenance assemblage dominated by the northern Chihuahuan obsidian source at Sierra Fresnal (Shackley 2005). The remainder of the artifacts are produced from one of the sources in the Jemez Mountains of northern New Mexico, but likely procured from Rio Grande Quaternary alluvium (see Church 2000; Shackley 2021). A brief discussion is offered below.

The analysis here of 132 artifacts from eight sites in Inyo County within the China Lake Naval Weapons Station indicates a relatively diverse provenance assemblage dominated by West Sugarloaf dome obsidian in the Coso Volcanic Field, as in all the previous studies by this laboratory, and all the artifacts were produced entirely from Coso Volcanic Field sources, Sugarloaf, West Sugarloaf, and West Cactus Peak domes (see discussion below). No sources outside the Coso field were present.

Both the artifacts were produced from the Valles Rhyolite (Cerro del Medio) source in the Jemez Mountains, northern New Mexico (Shackley 2005; Table 1 and Figure 1 here).

The analysis here of 6 obsidian artifacts from the Early Agricultural Las Capas site in the Santa Cruz River basin in Tucson, Arizona indicates a diverse provenance assemblage with sources all from one of the major Mogollon-Datil Volcanic Province sources in western New Mexico and eastern Arizona - Cow Canyon eastern Arizona, and Antelope Creek and North Sawmill Creek at Mule Creek, western New Mexico (Shackley 2005; Shackley et al. 2018). While the sample sizes are quite different, this obsidian provenance assemblage is quite different from the nearby and mainly contemporaneous Los Pozos that exhibited an obsidian provenance assemblage from all cardinal directions

The analysis here of 177 obsidian artifacts from the Cienega Phase Early Agricultural Los Pozos site in the Santa Cruz River basin in Tucson, Arizona indicates a very diverse provenance assemblage with sources in all Cardinal directions from the western and eastern Sonoran Desert, the Arizona Uplands, to northwest Mexico (Sonora and Chihuahua). Some of these sources (i.e. Cow Canyon) have been recovered from Los Pozos in the past as discussed below. The diversity of sources with a procurement radius of approximately 250 km in all directions was not evident before this, in part due to the rarity of obsidian in Cienega Phase sites in the Tucson Basin.

The analysis here of 195 obsidian artifacts from the surface and subsurface of Piedras Marcadas Pueblo ruin (LA 290) in the middle Rio Grande River valley indicates a source provenance similar to previous analyses of surface and subsurface contexts dominated by sources from the Jemez Mountains, both pre-and-post caldera. Most unique and important for the history of the site, and indeed the Coronado presence in the Middle Rio Grande valley is the occurrence of two polyhedral blade fragments produced from the Zinapecuaro obsidian source near the town of the same name in northeastern Michoacan state of west central Mexico

The analysis here of 195 obsidian artifacts from the surface and subsurface of Piedras Marcadas Pueblo ruin (LA 290) in the middle Rio Grande River valley indicates a source provenance similar to previous analyses of surface and subsurface contexts dominated by sources from the Jemez Mountains, both pre-and-post caldera, (Shackley 2009, 2013a, 2014a, 2014b). All these sources are present in the Rio Grande alluvium as far south as Albuquerque, although the Valles Rhyolite (Cerro del Medio) nodules are very small, probably too small to produce the one projectile point made from this source (Sample 1911; Shackley 2021). Mount Taylor is not available in Rio Grande Quaternary sediments this far north (Shackley 2021). Refer to Shackley (2021) for a thorough discussion of the sources and secondary distribution.Most unique and important for the history of the site, and indeed the Coronado presence in the Middle Rio Grande valley is the occurrence of two polyhedral blade fragments produced from the Zinapecuaro obsidian source near the town of the same name in northeastern Michoacan state of west central Mexico (see discussion below). This blade fragments from a source thousands of kilometers south into Mexico was most likely transported to the site during the siege of Piedras Marcadas by Coronado in 1540 by one or more of the West Mexican Indians traveling with Coronado. This source has never been recovered in the U.S. portion of the Southwest to my knowledge, and blade production after the Paleoindian period in North America was not practiced by native artisans (Bradley et al. 2010; Collins 1999). The only other obsidian Mexican artifacts recovered from Arizona and New Mexico are blades and blade fragments produced from one of the Sierra de Pachuca sources from Hidalgo state, Mexico, and no documented obsidian has been recovered in the Southwest from central Mexican or sources south of central Mexico other than these here and the four blades produced from Pachuca sources (Dolan and Shackley 2021).

The non-destructive whole rock EDXRF analysis here of source standards from the Lien Sunrise and Chicago iron mines and the Beach Paleoindian Cache in North Dakota indicate a good statistical correlation between the source rocks and the archaeological ochre (hematite) from the cache. An analytical trajectory of parametric and non-parametric multivariate and graphical statistical procedures was employed to determine source provenance (see Baxter 1994; Johnson and Wichern 1998; Shennan 1997; c.f. Zarzycka et al. 2019).

The analysis here of 63 obsidian artifacts (three are not obsidian) from five sites in southwestern Utah, indicates a source provenance assemblage with artifacts mainly produced from two sources in southwestern Utah, Modena in Iron County and Wild Horse Canyon in Beaver County, and the Kane Springs source in Lincoln County, Nevada (Haarklau et al. 2005; see cover image,Tables 1 and 2, and Figures 1 and 2).  One small piece of debitage was produced from the Obsidian Cliff source in the Yellowstone Plateau of northwestern Wyoming (source data at laboratory).  Obsidian Cliff obsidian does occur in early contexts throughout the West and into the Middle West (Beck and Jones 2011; Davis et al. 1995; Scheiber and Finley 2011; Shackley 2014, 2017).

The analysis here of 52 obsidian artifacts from two archaeological sites within the China Lake Naval Weapons Station, as in many of the previous studies, indicated the presence of mainly Coso Volcanic Field obsidian sources (Hughes 1988; Ericson and Glascock 2004; Shackley 2014, 2015a, 2015b, 2016, 2017, 2019a, 2019b).  As typical for sites on the weapons station, the assemblage is dominated by artifacts produced from the West Sugarloaf dome, followed by Sugarloaf and West Cactus Peak (Table 1 and Figure 1).  While there has been some argument that differential procurement of the Coso sources is not necessarily socially important, the work of Eerkens and Rosenthal at Coso suggests that there is some selection that may be socially significant (2004).  Unlike previous studies, however, two artifacts from CA-KER-8146 were produced from two of the localities at Casa Diablo in east-central California (Hughes 1994; Table 1 and Figure 1 herein)

The analysis here of 83obsidian bifaces (five were not obsidian or too burned/dirty to analyze) indicates an extremely diverse obsidian provenance assemblage with a mix of sources somewhat atypical for Classic contexts in the Middle Salt River Valley

The two artifacts from the Clovis site of Las Tortugas, Gran Desierto, northern Sonora are from one known and one as yet unlocated source: one piece of debitage from the Sauceda Mountains source in southwest Arizona, and one matching the composition of a single artifact recovered from the upper Rio Sonora in northern Sonora (Shackley 2005, 2019a). The biface, a possible Clovis fragment, produced from the source matching the one artifact from the Rio Sonora region is likely from a locality in northern Sonora, the location of which remains unknown. It does not match any known source in the Skinner/Shackley database of North American obsidian sources, including those in northwest Mexico (see Shackley 2005; Vidal-Solano et al. 2020; Table 1, Figures 1 and 2, see also cover image).

As we discussed, the obsidian biface was produced from the El Rechuelos Rhyolite obsidian source in the northern Jemez Mountains, northern New Mexico

The analysis here of four obsidian artifacts from AZ AA:12:312 (ASM) indicates procurement of both regional sources (Sauceda Mountains, western Arizona) and extra-regional sources (Antelope Creek/Mule Creek western New Mexico; Table 1 and Figure 1). These two sources are relatively common in Late Classic contexts in southern Arizona (i.e. Casa Grande, Marana), and Antelope Creek is a common source in this time period throughout the Southwest

The four pieces of obsidian debitage are allproduced from the Red Hill obsidian source located within a radius of two km, essentially on site(Table 1; Figure 1). This source is actually a discontinuous Neogene remnant rhyolite dome complex that has been partly subsumed by Quaternary mafic volcanism, much of it fissure flows that have formed mesas as well as cinder cones such as Red Hill (see http://swxrflab.net/redhill.htm; Shackley 1995, 2005)

Analyzed here is one obsidian artifact assigned to Valles Rhyolite (Cerro del Medio) from the Jemez Mountains in northern New Mexico and one ceramic sherd with a high alkaline composition (i.e. Na, Ca, K) that suggests a sedimentary origin rather than silicic (i.e. granitoid) residual clay origin (Table 1 and Figure 1; see discussion).

The non-destructive whole rock analysis here of three projectile point fragments from unknown provenience in the Tularosa Basin of southern New Mexico indicates that one of the artifacts was likely produced from the Socorro hydrothermally altered rhyolite, and one possibly from the Mount San Antonio dacite source in northern New Mexico, hundreds of kilometers north of the basin (see discussion).

The analysis here of 20 obsidian artifacts from four sites near Santa Fe, New Mexico indicates that all the artifacts were produced from one of three sources in the Jemez Mountains: Cerro Toledo Rhyolite, El Rechuelos Rhyolite, and Valles Rhyolite (Cerro del Medio; Table 1 and Figure 1)

The analysis here of 16 obsidian artifacts from the Corning Glass Museum indicates an extremely diverse provenance assemblage from five U.S. states and two states of Mexico. While it is difficult to determine whether all the artifacts were produced prehistorically (Cat. # 62.7.2B certainly was not, given its provenance), there are some inferences in this regard that can be made and are included in the discussion. Additionally, bibliographic citations and some comments on the sources in this collection are also offered

The analysis here of 71 artifacts (70 obsidian) from the Crosspatch site in southwestern Colorado indicates a very diverse obsidian provenance assemblage with artifacts produced from obsidian sources in northern and southwestern New Mexico, to northern Arizona, to southwestern Utah (Tables 1 and 2 and Figures 1 and 2). A short discussion of the results is offered below.

The San Jose point delivered by Joe Birkman was produced from El Rechuelos Rhyolite, a pre-caldera obsidian source in the northern Jemez Mountains of New Mexico (Shackley 2005).

The analysis here of eight obsidian artifacts so far recovered from the newly discovered Blue Canyon Clovis archaeological site southwest of Socorro, New Mexico indicates a diverse provenance assemblage including sources from the Mule Creek Source Complex in western New Mexico that must have been originally procured at the source, and Jemez Lineament sources from northern and northwest New Mexico, some probably procured from Rio Grande Quaternary gravels nearby, although the cortex on Samples 27 and 66 appears to be angular and not water eroded (see discussion below; Church 2000; Shackley 2005, 2009, 2012; Shackley et al. 2018)

The source provenance of the artifacts is dominated by Jemez Mountains sources(Table 1and Figure1; see Shackley 2016). Cerro Toledo Rhyolite obsidianis available as secondary deposits in Rio Grande Quaternary alluviumat least to Las Cruces, but Valles Rhyolite (Cerro del Medio) has not been found south of Albuquerque, and only as a few small diameter samples(Church 2000; Shackley 2005, 2013, 2020).

The analysis here of seven obsidian artifacts from CA-SBR-8334 within the China Lake Naval Weapons Station, as in many of the previous studies, indicated the presence of all Coso Volcanic Field obsidian sources (Shackley 2014, 2015a, 2015b, 2016, 2017, 2019a, 2019b). As typical for sites on the weapons station, the assemblage is dominated by artifacts produced from the West Sugarloaf dome, followed by Sugarloaf and West Cactus Peak

The analysis here of a sediment sample from a tuff strata on the south slope of Arroyo Hondo directly below the northwest corner of Arroyo Hondo Pueblo is a low-alkali andesite tuff based on the elemental composition

The analysis here ofone obsidian flake and one turquoise bead indicates that the obsidian artifact was produced from the Vulture source west of the Phoenix Basin, commonly recovered in Preclassic Hohokam contexts in the Lower Salt River Valley (Shackley 2005, 2019; Table 1 herein). A short discussion of the turquoise bead is offered belowas well.

The analysis here of six vitreous rock samples indicates trachy-andesite and basaltic trachy-andesite glasses according to an alkali/silica plot (Le Bas et al. 1986; Le Maitre et al. 1989; Table 1 and Figure 1 herein). Trachyte glass does occur in nature such as the Emuruangogolok volcano in Kenya, and a source in the Hawai'ian Islands, the former with SiO2 values over 62% by weight (Steve Lundblad, personal communication; Weaver 1977).

The analysis here of 18 obsidian artifacts from two sites, Wallace Ruin and Greenstone Pueblo (5MT6970, same site number for both sites), indicates a diverse source provenance assemblage with artifacts produced from the following sources in western North America: Jemez Lineament sources in northern New Mexico, Cerro Toledo Rhyolite, Valles Rhyolite (Cerro del Medio), El Rechuelos Rhyolite in the Jemez volcanic field, and Grants Ridge in the Mount Taylor volcanic field; northern Arizona, Government Mountain in the San Francisco volcanic field (see Shackley 2005), and sources in southeastern Idaho (Malad), and Wild Horse Canyon of southwestern Utah (Skinner/Shackley North American Obsidian Database; see Table 1 and Figure 1).  Both Wild Horse Canyon and Government Mountain have been recovered from sites examined by Crow Canyon Archaeological Center (Shackley 2014, 2017).  The Malad, Idaho source (over 600 km north of these sites) is not uncommonly recovered in Paleoindian and Archaic context throughout the West, particularly in the Southwest (Beck and Jones 2011).  In this region it is even more common than Obsidian Cliff in Yellowstone, one of the most commonly exchanged and recorded sources in North America (Beck and Jones 2011; Davis et al. 1995; Scheiber and Finley 2011).  While the sample is small, the obsidian from Greenstone Pueblo was the most diverse with all the sources from outside northern New Mexico, and indeed outside the Southwest.  Whether this is a real pattern or sampling error is impossible to know (see Table 1 and Figures 1, 2 and 3)

The analysis here of sixobsidianartifacts fromtwo Formative Period sites near Kelvin, Arizona along the Gila River indicates that all the artifacts were produced from the Superior (Picketpost Mountain) source approximately 25 linear kilometers north of the sites, and the nearest obsidian source (see cover image, Table 1 and Figure 1). Superior obsidian is also available as secondary deposits in Queen Creek Quaternary alluvium at least as far as Florence Junction (Shackley 1988, 1995, 2005).

The analysis here of 526 artifacts (524 obsidian) from the Archaic sites (n=69 and East, Middle, and West Trench recovery (n=455) by the University of New Mexico at Pueblo Bonito in Chaco Canyon is similar to the provenance assemblage from previous studies with some important exceptions (see Shackley 2016; Tables 1 through 4 and Figures 1 through 4).  While the assemblage is expectably dominated by debitage and utilized flakes produced from Jemez Mountains sources, a number of projectile points, and some debitage, were produced from sources throughout the U.S. West, west, north northwest, and south, of Chaco Canyon, including one piece of debitage from the Wild Horse Canyon source in west Utah over 500 linear km northwest.  The obsidian source assemblage from the late sites is derived from a very different mix of sources than the earlier sites from the large study done for Tom Windes over 15 years ago (Shackley and Dillian 2000; see also Duff et al. 2012; Shackley 2016).  The Archaic artifacts are mainly produced from Jemez Mountains or Mount Taylor sources.

The source provenance of the "lonely" bipolar core fragment is Cerro Toledo Rhyolite, and between the waterwom coftex and typical procurement in that par1 of New Mexico was likely procured lrom Rio Grande Quaternary alluvium where Cerro Toledo Rhyolite obsidian is the most commonlyrecovered secondarily deposited obsidian in the Rio Grande gravels at least as far as Las Cruces (Church 2000; Shackley 2005, 2020

The analysis here of 19 obsidian artifacts from 48PA3604 in Wyoming is dominated by Obsidian Cliff, Yellowstone Volcanic Field obsidian as in previous projects in the region, with two artifacts produced from the Malad, Idaho source (see cover image and Table 1 and Figure 1).  One artifact is produced from an, as yet, unlocated source that was not in the Skinner/Shackley North American obsidian source database.

The analysis here of 22 volcanic rock samples indicates a diverse set of volcanic rock types (Table 1, Figures 1 through 2).  The obsidian nodules collected from Turkey Ridge rhyolite on the NW side of Cerro Rubio are most definitely derived from the Cerro Toledo Rhyolite (CTR) event based on comparison with a large body of CTR source standards from Rabbit Mountain and the ash flow tuff to the south including "Obsidian Ridge" (see Shackley 2005; Table 2 and 3 and Figure 2 herein).  Using XRF the composition is well within those standards (see Table 2 and Figures 2 and 3).

The analysis here of 65 artifacts, 64 obsidian, from archaeological contexts in Washington County, southwest Utah indicates procurement of the raw material for production of the artifacts from southeastern Nevada, and southwestern Utah, essentially some of the nearest regional sources of archaeological obsidian

The analysis here of 300 artifacts (12 not obsidian and a few not analyzed) from three sites (SON:F:2:4, 61, and 82) in the Valle de Altar in the northern State of Sonora, Mexico indicates a very diverse provenance assemblage with known sources on both sides of the border, including Arizona, New Mexico, Chihuahua and Sonora, and a large proportion of, as yet, unlocated sources (73.9%) dominated by one unusual trachyte obsidian source (72.9%). The main unknown source is likely located somewhere along the Río Altar or somewhere above that stream basin, and called provisionally here SON Valle de Altar Unknown. The diversity of obsidian source provenance decreases from west to east as the unknown source dominates the assemblage (see cover image). This study is one of the largest archaeological obsidian provenance studies in Sonora, and despite the number of "unknown" sources provides a good basis for further archaeological and geoarchaeological research in Sonora (see also Shackley 2019a).

The mix of sources is similar to the previous study (Shackley 2019a) with none of the sourcesto the west of the Sierra Madre ridgeline in Sonora (see Table 1 and Figure 1; Kibler et al. 2014; Shackley 2005). The TX UnknownA type is also present as well as Mount Taylorobsidian(Grants Ridge) the latter most likely procured from Rio Grande Quaternary alluvium, and two Chihuahuan sources(Lago Fredrico and Lago Barreal) the latter present in the previous study(Church 2000; Shackley 2012).See previous study for a more extensive discussion of sources and regional geology (Shackley 2019b).

The analysis here of 16 obsidian artifacts from three sites in central Colorado indicates a dominance of artifacts produced from the Valles Rhyolite (Cerro del Medio) dome in the Jemez Mountains of northern New Mexico. One artifact was produced from the El Rechuelos Rhyolite domes in the Jemez Mountains, and one artifact was produced from the Cochetopa Dome in Saguache County, Colorado. An earlier study of 5PA4803 also indicated procurement of obsidian from these two Jemez Mountains sources (Shackley 2017)

The analysis here of 18 biface and projectile point samples from Santee Greens indicates a high proportion of rhyolite followed by chert raw materials. A few of the artifacts may be from either the Piedra de Lumbre chert source in northern San Diego County, or one of the Santiago Peak Volcanic rhyolite sources from anywhere in Orange or San Diego Counties or northern Baja California. One of those artifacts could be produced from the Lusardi Formation Santiago Peak Volcanics source near Poway, California, also in northern San Diego County. A discussion of these issues follows the laboratory instrumentation discussion.

The analysis here of 23 obsidian artifacts from two sites within the China Lake Naval Weapons Station, as in many of the previous studies, indicated the presence of all the Coso Volcanic Field obsidian sources (Shackley 2014, 2015a, 2015b, 2016, 2017, 2019a, 2019b). In this case West Sugarloaf (69.6%) is dominant followed by Sugarloaf (13%) and Joshua Ridge and West Cactus Peak each at 8.7%

The analysis here of 10 obsidian artifacts from four sites along the Middle Rio Grande indicates procurement from one of three sources in the Jemez Mountains, all of which are available in Quaternary sediments nearby on the eastern terraces of the Rio Grande (Shackley 2005, 2012; Table 1 and Figure 1 here). Most of the artifacts were produced from the Cerro Toledo Rhyolite obsidian source, the most commonly recovered source in Rio Grande alluvium between the Jemez Mountains and Chihuahua

The analysis here of five obsidian artifacts from 41PT501 in north Texas indicates that all the artifacts were produced from the Cerro Toledo Rhyolite obsidian source in the Jemez Mountains of northern New Mexico (Table 1 and Figure 1). Cerro Toledo Rhyolite obsidian along with Valles Rhyolite (Cerro del Medio) obsidian was the most commonly procured from the Jemez Mountains sources (Shackley 2005; Shackley et al. 2016).

The non-destructive whole rock analysis here of 17 obsidian artifacts from archaeological contexts along the Middle Awash River Basin, Ethiopia indicates a very diverse obsidian provenance assemblage similar to the diversity seen in the Negash et al. (2011) study including known and, as yet, unlocated sources. Many of those artifacts were analyzed at the Berkeley Archaeological XRF Laboratory using similar methods and calibrations (see Shackley 2005, 2019:Supplement). The results here were compared to the Negash et al. (2011) study as well as source standard data at this laboratory.