SORT : Stanford Obsidian Research
Team
Background
Ours is a small research group dedicated to the trace elemental characterization
of archaeological obsidians via the instrumental facilities of the department
of Geological and Environmental Sciences at Stanford University. The
group is part of a wider network of labs and on-going archaeometric
projects detailing the exchange and use of obsidians in the prehistoric
Old and New Worlds, via the research of Tristan Carter, Lecturer in
the Department of Cultural and Social Anthropology. The work at Stanford
has an avowed inter-disciplinary approach, involving researchers from
the Departments of Anthropological Sciences, Cultural and Social Anthropology,
plus Geological and Environmental Sciences. Moreover, it offers an important
context for the development of undergraduate research. While the two
projects that form the core of the first SORT research are designed
carefully to be discretely bounded studies that are aimed to be completed
within an academic year, both represent springboards for future analyses
that we hope will involve more undergraduates in the future.
Projects
The starting point of our research is two sets of material from excavations
in Peru and Turkey, both of which are directed by current Stanford Faculty.
Çatalhöyük-West (Turkey)
The world famous prehistoric site in central Anatolia comprises two
artificial mounds (or tells) that rise above the Konya Plain. The larger,
earlier and better known mound is Çatalhöyük-East,
whose occupation spans the Aceramic Neolithic to Early Neolithic (c.
7400-6200 cal BC). This large village appears then to have been abandoned,
with the inhabitants shifting a few hundred meters away, across the
Carsamba River, to establish a new settlement at Çatalhöyük-West.
Recent radiocarbon determinations suggest that this village was occupied
between c. 6000 – 5500 cal BC, or the Early Chalcolithic I-II
[ECI-II] period in archaeological terms (the earliest levels have yet
to be exposed and dated, hence the apparent hiatus between the two mounds).
For both communities the primary raw material employed to manufacture
their flaked implements was obsidian (usually >90% of any assemblage),
despite the fact that the nearest sources of this volcanic glass are
located 120 miles to the north-east, in the region of Cappadocia. It
has long been argued that this was an extremely valuable resource to
Çatalhöyük, not only with regard to its functional
capabilities and daily household use, but also in terms of the community’s
(alleged) role in its long-distance exchange and its symbolic properties.
In 1999 a major characterization program was initiated dedicated to
sourcing Çatalhöyük’s obsidian through time.
This work, under the directorship of Carter, involves a number of different
laboratories and instrumental techniques, specifically: CNRS / Grenoble
(ICP-MS/AES), CNRS / Bordeaux (PIXE, SEM-EDS), University of Aberystwyth
(LA-ICP-MS), University of California, Berkeley (XRF-EDS). Some 277
samples have now been analyzed within this project, of which the results
from 135 are currently in press, while the other data sets are being
prepared for publication. The artifacts characterized have derived mainly
from Çatalhöyük-East, spanning the basal Aceramic Neolithic
(Level Pre-XII.D) to upper Early Neolithic (Level III) occupation layers.
Thus far only seven pieces of obsidian from Çatalhöyük-West
have been analyzed, it is the aim of our new work at Stanford to investigate
further the material from the Chalcolithic period.
The 49 artifacts that form the basis of Stanford data-set come from
the excavation of a mudbrick structure (Building 25) and various refuse
pits whose contents span the ECI-II. The sampling strategy was designed
to select a representative range of raw materials in terms of the variations
in color, banding, texture and translucency represented within the assemblages
under consideration. It also attempted to select items that were diagnostic
of the various knapping traditions, or industries documented in the
Çatalhöyük-West material.
The significance of this project is manifold. Firstly it will increase
the number of samples from this part of the site so that we may have
a more confident notion of which obsidian(s) were being procured by
the EC community and – hopefully – in which form(s) these
glasses were circulating. Secondly, it will increase the time depth
represented within our characterization study, allowing us to appreciate
the long-term history of obsidian exploitation at Çatalhöyük.
Thirdly, by examining material from Chalcolithic levels we can start
to address the question of what was occurring at the quarries at this
time, a period for which we have very little information. Fourthly,
by focusing on Early Chalcolithic data we will be helping to redress
a research bias in Anatolian / Near Eastern / Cypriot obsidian characterization
studies, namely the overwhelming focus on material from Neolithic contexts.
Previous results
The seven obsidian artifacts analyzed previously from Çatalhöyük-West
were provenanced to the southern Cappadocian volcanoes of Göllü
Dag-east (n=3) and Nenezi Dag (n=4). These appear to have been Çatalhöyük’s
primary sources throughout its occupation, albeit with important differences
in the history and form of their use (e.g. Figure 1).
Figure 1: Combined results of the 235 artifacts thus far analyzed from
Çatalhöyük, by level (one sample assigned to Acigöl
West).
Project personnel: Tristan CARTER (CASA), Rachel KING (undergrad), Guangchao
LI (GES) and Gail MAHOOD (GES).
Chavín de Huántar (Peru)
The UNESCO World Heritage site of Chavín de Huántar is
located in the north-central sierra of Peru, along a natural access
route between the coast and eastern tropics.
The ceremonial center sits at 3150 m elevation in a high valley on
the eastern side of Peru’s Cordillera Blanca, at the confluence
of the Mosna and Wacheqsa rivers. The site, a complex of stone-faced
platform mounds, terraces, and sunken plazas, dates to roughly 1500-500
BC. The platform mounds are built over a complex and interconnected
accretion of subsurface galleries that have been home to some of the
most spectacular archaeological finds at Chavín and have figured
prominently in reconstructions of ceremonial practice at the site.
One of only a handful of monumental highland sites from this early period,
Chavín has been the subject of interpretive extremes. These vary
about two major axes: the nature of Chavín’s apparently
pan-Andean influence and the interpretation of its development. Along
the first axis, Chavín has been described as the center of Peru’s
autochthonous mother culture at one extreme and suggested as a relatively
late and synthetic center of cultural developments derived from the
coast at the other. Along the second axis, Chavín has been variously
interpreted as a center of coast-jungle cultural synthesis, a pilgrimage
and cult center with ideological sway over much of the Central Andes,
and a locus of the development of authority and social complexity.
Given the historic research interest in the nature of Chavín’s
relationship to the rest of Peru (i.e. as source, or perhaps simply
exemplar, of the first pan-regional ideological system to develop in
Peru), the source characterization of obsidians found at the site is
a natural focus of further research. The extent and nature of Chavín’s
contacts with contemporary ceremonial centers, both in the highlands
and on the coast, was certainly linked to the circulation of valuable
materials like obsidian, which likely played a significant ceremonial
as well as economic role. Excavations at Chavín have generally
found obsidian to be widely present but never abundant, likely reflecting
the difficulty in obtaining an exotic raw material from nearly 600 air
km away.
Previous research by Burger found the overwhelming majority of obsidian
samples from Chavín to come from the Quispisisa obsidian source,
some 580 km to the south. The last decade of excavation at the site
has provided an assemblage from more diverse and better-dated contexts.
Internal variation in the use and ability to procure obsidian remains
under-examined, and it remains to test the current presumption that
Chavín’s obsidian was overwhelmingly from the Quispisisa
source. Ultimately, such research will fit into an emerging understanding
of the patterns of obsidian procurement and circulation in the Formative
Period Andes.
Project personnel: Tristan CARTER (CASA), Dan CONTRERAS (AnthSci), Guangchao
LI (GES), Gail MAHOOD (GES), Kristin NADO (AnthSci undergrad), John WOLFF
(AnthSci).
Undergraduate Training
A central component of SORT’s aims are the inclusion of undergraduates
within the project from the outset, to be involved in selecting the
artifacts for analysis, processing the samples, interpreting the data
and to contextualize the results through more general research upon
the area and period under consideration. It is envisaged that the training
will take the form of formal class time and dedicated research supervision.
With regard to this year’s research we have established the following
structure and timetable:
(i) Student to take the Geoarchaeology class offered in the winter
term taught by Gail Mahood and Sid Carter (Arch/GES 186).
(ii) Student to register with Gail Mahood for weekly directed undergraduate
research through winter and spring (GES 192) – units to be decided.
(iii) Student to meet weekly on informal (no unit accredited) meeting
with Tristan Carter to discuss archaeological context.
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