© 2015 European Association of Geoscientists & Engineers 557
Near Surface Geophysics, 2015, 13, 557-569 doi:10.3997/1873-0604.2015029
*
c.gaffney@bradford.ac.uk
Still searching for graves: an analytical strategy for
interpreting geophysical data used in the search for
“unmarked” graves
C. Gaffney
1*
, C. Harris
1
, F. Pope-Carter
1, 3
, J. Bonsall
1, 2
, R. Fry
1
and A. Parkyn
1
1
School of Archaeological Sciences, Faculty of Life Sciences, University of Bradford, Bradford BD7 1DP, UK
2
Institute of Technology Sligo, Sligo, Ireland
3
GSB Prospection Ltd (SUMO), Bradford BD13 3HW, UK
Received December 2014, revision accepted March 2015
ABSTRACT
Searching for and mapping the physical extent of unmarked graves using geophysical techniques has
proven difficult in many cases. The success of individual geophysical techniques for detecting graves
depends on a site-by-site basis. Significantly, detection of graves often results from measured contrasts
that are linked to the background soils rather than the type of archaeological feature associated with
the grave. It is evident that investigation of buried remains should be considered within a 3D space as
the variation in burial environment can be extremely varied through the grave. Within this paper, we
demonstrate the need for a multi-method survey strategy to investigate unmarked graves, as applied at
a “planned” but unmarked pauper’s cemetery. The outcome from this case study provides new insights
into the strategy that is required at such sites. Perhaps the most significant conclusion is that unmarked
graves are best understood in terms of characterization rather than identification. In this paper, we
argue for a methodological approach that, while following the current trends to use multiple tech-
niques, is fundamentally dependent on a structured approach to the analysis of the data. The ramifica-
tions of this case study illustrate the necessity of an integrated strategy to provide a more holistic
understanding of unmarked graves that may help aid in management of these unseen but important
aspects of our heritage. It is concluded that the search for graves is still a current debate and one that
will be solved by methodological rather than technique-based arguments.
In his seminal paper on this subject, Bevan stated that, while
ground penetrating radar (GPR) has had the greatest success at
locating unmarked graves “…surveys have found no guarantee of
success. Geophysical evidence has suggested that there were
graves where there were none; known graves have also been invis-
ible to these surveys” (Bevan 1991). His case studies are based
around historic cemeteries where the markers have been lost or
destroyed, and the discussion primarily revolves around GPR trav-
erses and small-scale electromagnetic area survey. It is evident that,
in the intervening years, the techniques that are available in the
study of grave sites have advanced. Despite that assertion, in our
opinion, the methodologies that provide the platform for analysis
have not progressed accordingly, although there have been some
recent and important advances that standardize the outcomes
(Ruffell and McAllister 2015). With that in mind, the geophysical
approach to the study of graves requires reconsideration.
HIGH ROYDS PSYCHIATRIC HOSPITAL
This case study presents the High Royds Memorial Gardens of
Menston, West Yorkshire (Fig. 1). The survey was undertaken
INTRODUCTION
The location of human burials or the investigation of the struc-
tures that house the dead has long been an objective of archae-
ogeophysicists (e.g., Lerici 1959). Burials that are monumen-
tal in nature are often easy to identify (Aspinall, Gaffney, and
Schmidt 2008). Meanwhile, mapping individual unmarked
graves is often reported to be less successful (Hansen, Pringle,
and Goodwin 2014). This underachievement is particularly
acute when considering the need for geophysical investigation
for modern forensic applications that have the added
parameter of short-term temporal changes (Lynam 1970; Bray
1996; Cheetham 2005; Pringle et al. 2012a; Jervis and Pringle
2014). The archaeological situation for unmarked graves is
often predicated on a lack of context and an unknown suite of
characterization variables. Given this background, it is
surprising that grave prospection is often undertaken only
employing one technique (Conyers 2006; Bigman 2012;
Ruffell et al. 2009).