INAA TESTING OF ARCHAEOLOGICAL AND GEOLOGICAL SAMPLES FROM THE
WOMAN RIVER IRON RANGE AND ADJACENT AREAS
by
Nick Adams
Introduction
During archaeological surveys in the Sudbury District of northeastern Ontario,
artifacts made from a lithic raw material, not previously described in the
archaeological literature of the region, were recovered. A probable nearby
source - the Woman River Iron Range - was identified by process of
elimination. A research grant from the Ontario Heritage Foundation enabled the
author to collect additional samples from archaeological and geological
sources and subject them to Instrumental Neutron Activation Analysis in an
attempt to pin down the source of the archaeological materials. Although this
did not prove possible, it is clear from the results that the lithic material
tentatively referred to as "Woman River Chert" is from a single
geological source. During archaeological surveys of the headwaters area of the
Upper Spanish and Mississagi Rivers, for the Ontario Ministry of Natural
Resources (Adams 1991a, 1991b), artifacts made of distinctive fine dark red to
orange jasper, a high quality white to grey translucent chert with darker grey
black to black streaky inclusions, and a more homogenous and lower grade grey
to blue-grey banded chert were recovered. Close examination of the
archaeological samples revealed that fragments of jasper-like material could
be seen adhering to natural fracture plains on the finest quality chert and
that reddish banding was present in other pieces, indicating some
stratigraphic connection exists between the two materials. Furthermore, since
the archaeological samples included a preponderance of large primary flakes
and shatter fragments, a non-too-distant source could be postulated (William
A. Fox, Personal Communication). In addition some flakes of the high grade
translucent chert also had fragments of the lower quality bluish-grey material
attached. Clearly a direct stratigraphic link exists between the jasper, the
high grade chert and the lower quality material. During background research
for the Mississagi River and Biscotasi Lake archaeological surveys, the
presence of a jasper and chert producing geological formation the Woman River
Iron Range had been identified as a possible significant lithic tool stone
source (Emmons and Thompson 1929; Goodwin 1965). With the financial assistance
of an archaeological grant (ARG -634) from the Ontario Heritage Foundation, a
field trip to the probable geological source of Woman River Chert was
undertaken (Adams 1994). Samples of geological materials were collected from
outcrops, and also from mining drill cores found in the area. Archaeological
samples were also recovered from newly discovered archaeological sites close
to the presumed source of the material. Portions of these materials, along
with some fragments of mining cores from other parts of the Woman River Iron
Range, artifacts from Upper Spanish River and Upper Mississagi River
archaeological sites, and from archaeological sites on the Woman River were
submitted for Instrumental Neutron Activation Analysis (INAA) to the
Slowpoke-2 Facility at the Royal Military College of Canada, Kingston,
Ontario.
Process of INAA testing
Materials for sampling were detached from their host rock using a hardened
metal punch. The host artifact was held in a vice and small flakes and
fragments were punched off onto a clean cloth. These were then collected and
added into small 1 c.c. containers (one per sample) until each container was
full. Inevitably this has meant that the actual mass of the sample material
differs from one sample to another which may have led to some inaccuracies in
the final results. Each sample was then exposed to the RMC reactor for 1
minute at = 5 x 1011 neutrons. cm2 sec1 The samples were first counted after 5
minutes then a second count was conducted after 20 minutes. The following
elements were detected in the samples: aluminum (Al), barium (Ba), calcium
(Ca), ch lorine (Cl), copper (Cu), potassium (K), magnesium (Mg), manganese (Mn),
sodium (Na), silicon (Si) and vanadium (V).
Limitations
The numerical data from the I.N.A.A. testing must be treated with caution
because of the different volumes of the samples examined. Reduction of all
samples to powder of similar volume had been considered before testing
commenced. Unfortunately, the equipment readily available for this purpose was
not sterile. Rather than introduce new and unwanted contaminants into the
samples, it was decided to proceed with what was available and accept any
shortcomings inherent in this process. A far larger range of samples would
have been preferable, especially if it had been possible to locate a worked
outcrop or chert or jasper in the field. Since this was not the case, and
since samples of chert and jasper from known geological contexts were
available, it was decided to proceed with what was on hand. Fortunately,
archaeological samples from a variety of contexts were accessible, thus it has
been possible not only to look at possible relationships between source
materials and artifacts, but between artifacts from different parts of the
region.
Analysis
An F-test of the I.N.A.A. results for selected pairs of samples was undertaken
using the built in F- test tool in Borland Quattro Pro 5.0. This was done in
an attempt to determine the variances between specific sets of samples, since
if the variances of the two data sets are significantly different, it can be
assumed that they were drawn from different parent populations. Samples chosen
for this testing were selected on an intuitive basis. In some instances
samples from the same source were chosen for comparison; in others, both
archaeological and geological samples from widely disparate provenience were
tested against each other. Since silica formed such a large percentage of each
of the samples tested, this element was left out of the F-test parametres.
Interpretations and Conclusions
A wide range of results was acquired from the F-tests performed on the data
from I.N.A.A. testing. Some of the results appeared to confirm intuitive
expectations: others diverged considerably from what was either expected, or
appeared reasonable to expect. The results strongly suggest that the jasper
used on sites at Ramsey, Biscotasi and Kashbogama Lake are from the same
geological source. They also suggests that the grey chert samples from the
various sites on these lakes were also from a single source. Furthermore, the
closeness in F- test results between jasper and grey chert flakes from sites
on these lakes suggests that a strong geological linkage between these two
materials is apparent. F-tests between jasper samples from an archaeological
site on the Woman River at the location where the Woman River Iron Range
crosses, and archaeological sites on the Woman River (F=1.38), Ramsey Lake
(F=1.36), Ramsey Lake (F=2.23) and Kashbogama Lake (F=1.08) also suggest that
these all derive from the same source. Unfortunately, when samples of the
archaeological materials were compared to samples of geological source
materials, the results were less informative. While F-test results from the
geological samples appeared to suggest that these materials were related (as
one might expect), no corresponding relationship was evident when they were
compared with the archaeological samples.
Summary
The results from the I.N.A.A. testing and the subsequent F-test analyses have
revealed some interesting patterns. It seems clear that all the archaeological
artifacts of jasper which were tested are closely related, and probably derive
from a common source. Similarly, the artifacts of grey, translucent chert all
appear to be related - and also appear to be closely related to those of
jasper. It seems reasonable to suggest a single quarry source for all these
archaeological materials (especially since flakes containing bands of jasper
and chert have been found on archaeological sites in the region). But whether
the source for the archaeological materials occurs within the Woman River Iron
Range has not been established. While close correlations between the various
geological samples were clear, no link between these samples and the
archaeological artifacts has been established. This result appears to disprove
the original, albeit intuitive hypothesis that the Woman River Iron Range was
the source of the raw materials for the artifacts. However, it is worth
remembering that the geological samples were all derived from mining drill
cores and did not come from outcrops or exposures which would have been
available to native stone tool makers. The depths from which these cores were
extracted are not known. At this time it seems premature either to reject, or
accept the Woman River Iron Range (and its associated geological occurrences)
as a source of the jasper and grey chert artifacts manufactured by native
people at the headwaters of the Spanish / Groundhog / Mississagi River
systems. It is the belief of this author that it is still the most likely
candidate, and that future efforts to identify outcrops and possible quarry
areas would be worthwhile.
References
Adams, N and S. Errington
1991a "A Cultural Resources Inventory of the Mississagi River
Provincial Park". Report prepared for the Ontario Ministry of Natural
Resources, Chapleau District.
1991b "A Cultural Resources Inventory of Biscotasi Lake Provincial
Park". Report prepared for the Ontario Ministry of Natural Resources,
Chapleau District.
Adams, N
1994 "Tracing "Woman River Chert" to it's Source: INAA
testing of archaeological and geological samples from the Woman River Iron
Range and adjacent areas". A report prepared for The Ontario Heritage
Foundation in fulfilment of Archaeological Grant ARG-634.
Emmons, R.C. and Ellis Thompson
1929 "Preliminary Report on Woman River and Ridout Map-Areas, Sudbury
District,Ontario". Canada Department of Mines, Geological Survey,
Canada. Ottawa.
Goodwin A.M.
1965 "Geology of Heenan, Marion and Northern Part of Genoa
Townships". Geological Report No.38, Ontario Department of Mines.
Article originally published in Annual Archaeological
Report, Ontario, Volume 6 (New Series) 1995. Reproduced here courtesy of
the Ontario Heritage Foundation.
Back to www.adamsheritage.com
|
