Forensic Science International 202 (2010) 9–12

Review

Forensic pedology, forensic geology, forensic geoscience, geoforensicsand soil forensics

Alastair Ruffell *

School of Geography, Archaeology & Palaeoecology, Queen’s University Belfast, Elmwood Avenue, Belfast BT7 1NN, Northern Ireland, United Kingdom

Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

1.1. Early work (pre-2003) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

1.2. Recent developments (post-2003) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

2. Forensic pedology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

3. Forensic geology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4. Forensic geoscience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

5. Geoforensics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

6. Soil forensics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

7. Environmental forensics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

8. Discussion and summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

A R T I C L E I N F O

Article history:

Received 15 February 2010

Received in revised form 30 March 2010

Accepted 31 March 2010

Available online 28 April 2010

Keywords:

Forensic pedology

Forensic geology

Forensic geoscience

Geoforensics

Soil forensics

Environmental forensics

A B S T R A C T

We now have a confusing set of five commonly used terms for the application of Earth evidence in

forensic science. This confusion is resulting in Earth scientists who use these methods mentioning

different terms, sometimes for the same type of study. Likewise, forensic scientists, police/law

enforcement officers and those employed by courts of law are becoming confused as to what each term

means. A nomenclatural framework (based on the first use of each term) is proposed to encourage

consistency in the use of terminology. Generally, the number of Earth science applications has grown

through time, from soil and sediment analysis to remote sensing and GIS. The issue of where forensic

biology and microbiology sits with these uses of Earth evidence is considered.

� 2010 Elsevier Ireland Ltd. All rights reserved.

Contents lists available at ScienceDirect

Forensic Science International

journal homepage: www.elsev ier .com/ locate / forsc i in t

1. Introduction

For forensic scientists and geologists/geoscientists alike, thereare now a number of confusing terms for the application of thesedisciplines to forensic science (cf. criminalistics in some countries).Historically these include Forensic Pedology (soil science); ForensicGeology; Forensic Geoscience; Geoforensics, Soil Forensics andEnvironmental Forensics. Rather than attempt a standardisation orintroduce a new, less-confusing overall term, this article uses an

* Tel.: +44 28 90973407; fax: +44 2890321280.

E-mail address: a.ruffell@qub.ac.uk.

0379-0738/$ – see front matter � 2010 Elsevier Ireland Ltd. All rights reserved.

doi:10.1016/j.forsciint.2010.03.044

analysis of what the originator(s) of each term included in their overtor implicit definition to define what is included, and thus informwhat term is most appropriate. This work is not intended to be areview of the use of soils, geology and Earth science in forensics;hence publications that do not ascribe a name to the studyundertaken are not dealt with in detail. It is clarification of what eachname or term means that this work seeks to achieve.

1.1. Early work (pre-2003)

Early work on, and mentions of, the use of Earth materials inforensic science concern sediment and soil. It is thus ratherperverse that a mention of sediment forensics has never been

A. Ruffell / Forensic Science International 202 (2010) 9–1210

made and soil forensics has only recently been used. The ScientificAmerican (1856 [1]) records perhaps the earliest use of sedimentanalysis in forensics, whereby Christian Ehrenberg, the famousBerlin professor was asked to analyse some sand. This had beenrecovered from barrels that were supposed to contain silver coins,yet somewhere along the railway between their origin anddestination a classic case of substitution had occurred: the coinswere replaced by sand. Ehrenberg had sand collected from eachstop the train had made and indicated the station where the swophad been made. Interviews by the police established a possiblesuspect, who confessed. The subsequent stories of Arthur ConanDoyle (1887–1907 [2]), and criminal cases of Hans Gross (1962[3]), Georg Popp (1910 [4], 1939 [5]), Oscar Heinrich (active in the1920s and 1930s, see [6]) and Edmond Locard, established thestudy of soil, sediment, landforms as useful in forensic science andcriminal investigations. None of the above authors created a termfor their work, as they were investigators first and foremost, usingall the evidence available, as opposed to Earth scientists, who havecreated the problem of nomenclature this article seeks to address.Forensic work on soil and sediment continued through the inter-war years and between 1945 and 1960s: the FBI (starting in the1930s), Camps (1962 [7]) used soil and sediment in cases ofcomparison/exclusion, intelligence gathering and substitution.None of these authors/workers used a term for their work; onlyBrooks and Newton (1969 [8]) used a phrase and called their work‘forensic pedology’ (see below). Through the 1960s, 1970s and1980s work was carried out on soil for exclusionary/comparativeforensic work at the FBI laboratories, the UK’s defence laboratory(Aldermaston), in police laboratories in Germany, France and theUnited Kingdom, amongst others. Consequently, a review of theliterature from 1965 to 2000 in Murray’s [9] bibliography shows 24articles on the use of soil and/or sediment in criminal investiga-tions. Critically for this review however, none of these authorsproffered a name for what they were doing: most were mentionedby the name of the technique (colour, density gradient column) asapplied to soil or used the word soil as the material to be analysed.As we will see (below) it was in 1968 (forensic pedology), 1975(forensic geology), 2002/2004 (forensic geoscience), 2008 (geofor-ensics and soil forensics) that a series of names appeared for suchwork, that has led to the current confusion this article aims toclarify.

1.2. Recent developments (post-2003)

Since 2003 there have been specialist forensic geology/geoscience/soil meetings throughout the world, including threesessions of the Geological Society of America (Philadelphia, 2006;Denver, 2007; Houston, 2008) and a public forum at the annualmeetings of the Geological Society of America (Denver, 2007), fourmeetings of the Geological Society (London, 2003, 2004, 2006,2008) and two entitled ‘International Soil Forensics’ (Australia,2006; Scotland, 2007). Further meetings of all these groups areplanned, suggesting that the use of different geoscience methods,Earth materials and soil analysis are important to forensic science.This contention is supported by the number of books published inthis area [9–14] as well as articles in the forensic science literature(see reference list). The volume of meetings and publicationsappears to be good news for both non-forensic Earth sciencespecialists wishing to apply their knowledge to a new arena, aswell as forensic scientists looking for evidence or conductingsearches. However, many of the above meetings and publicationshave used different titles for their works, creating confusionamongst both specialists and would-be users (investigators). Thecurrent titles include (amongst others): forensic pedology; forensicgeology; forensic geoscience; geoforensics; soil forensics; envi-ronmental forensics. At the International Crime Science Confer-

ence (British Library, July, 2009) one of the authors of this work co-presented a paper on forensic geology [15] in which they outlinedthe above problem of too many names and considered twosolutions. First would be to abandon all previous names andprovide one, suitable, all-encompassing, neutral term that carriesno previous meaning (e.g. Earth forensics). The second solution isto ensure that the origin and meaning of the various terms isexplained clearly in a mainstream scientific journal and that thenames are used appropriately. As each of the names does have adistinct application and pedigree, this latter solution is preferred.This work sets out to define and explain each of the commonlyencountered names, such that both specialists and non-specialistsalike can speak a common language and avoid misunderstanding.

2. Forensic pedology

Although the famous forensic practitioners like Ehrenberg,Gross, Popp, Locard and Heinrich (see [10,12,13]) all use the wordsoil (the scientific study of soil being pedology) and either mentionpossible applications or detail actual cases, none of them applied adirect name for, what was back in the late 1800s to mid-1900s, aspecialized study. Even in 1967, when the above workers hadachieved numerous successes with the forensic/legal study of soiland sediment, the classic textbook of it’s day [16] did include muchon soil analysis and geology, but again no name was applied. Withthe publication of Brooks and Newton’s (1969 [8]) ‘forensicpedology’ article, so a named sub-discipline in the forensic scienceswas established. Brooks and Newton’s article effectively pre-empted later authors (see below) in summarising how variable themineralogy of sediment and soils is, and how this may lead to a soilor sediment having a unique, or almost unique identity. Thismakeup could then be used to compare, or better exclude, soil orsediment from questioned (e.g. a suspect or deceased victim) to alocation of a scene of crime.

3. Forensic geology

When the first use of forensic geology [11] was made in a widelyaccessible publication, the authors were referring largely to themethods of geological analysis of soil and sediment analysis, ratherthan the historic precedence in the type of material (soil) beinganalysed. Thus in later definitions of forensic geology, Murray [9] isat liberty to mention the methods of geophysics, as indeed this iswhat they are—methods of analysing Earth materials for assistingcriminal investigations. However, the core methods referred to byMurray and Tedrow (1975 [11]) and Murray (2004 [9]) are those ofsoil and sediment description and analysis by petrography andmineralogy. Forensic geology should thus be used when descrip-tion by hand specimen, light microscope and petrographicmicroscope is being made of soil, sediment and containedgeological materials (e.g. fossils). In addition, grain size, sorting,grain shape and grain surface are included in the descriptiveaspects of forensic geology. Forensic geology also includes analysisof mineralogy (thin section petrography, X-ray diffraction),particle size (by sieving and weighing) and chemistry (includingXRF, ICP, FTIR, microprobe, amongst others). Pye [12] sticks verymuch to this clear and precise definition, with further case studiesand more detail on analytical methods such as geochemistry andSEM.

4. Forensic geoscience

The first published use of this term was in websites containinginformation for, and an edited book resulting from, a conferenceorganized at the Geological Society of London in 2002 (papers fromthis meeting published in Pye and Croft’s edited book [10]. The

A. Ruffell / Forensic Science International 202 (2010) 9–12 11

organizers had correctly gauged the interest such a meeting wouldgenerate, as the meeting ran to a programme over two days, andincluded far more than routine applications (e.g. the use of mud onsomeone’s shoe being used is exclusionary or associativeevidence). Although the various papers within [10] do indeedhave such soil and sediment analysis at their core. Geophysics,bedrock geology, microfossils and microorganisms, statistics andthe geological analysis of unusual materials (e.g. spacecraftsurfaces) were included, hence the use of ‘geoscience’ in the title.Simultaneously to the editing of [10], Elsevier Europe commis-sioned the writing of an all-encompassing article on all aspects ofthe application of geological and geoscience methods to forensicscience [17]. These authors included remote sensing, GIS(geographic information systems), as well as the varied methodsand applications contained in [10] in their article. To summarise,the most-widely accessible publications that can assist us inproviding guidance on the most appropriate use of this term are[10,17]. Neither of these works contradict each other, anddemonstrate that forensic geoscience has its pedigree in forensicgeology but also includes geophysics, bedrock geology, hydrody-namics, GIS, geostatistics as well as some specialist analyticaltechniques including bone taphonomy, isotope analysis and theSEM-microprobe method of QemScan.

5. Geoforensics

As a term, this was first used to name a commercial consultancynamed geoforensics, and used in a publication by [13] toencompass all that had gone before (pedology, geology, geosci-ence) but also include geomorphology, geography, geostatistics,remote sensing, human geography/sociology. Just as Pye and Croft[10] used ‘forensic geoscience’ and included more disciplines(detailed chapters on geophysics, unusual applications [e.g.spacecraft surfaces], statistics) than in [9], so Ruffell and McKinley[13] expanded forensic geoscience even further, with chapters onremote sensing, geomorphology and GIS, some applied to humangeography and sociology. Thus, through the evolution of thesethree books [9,10,13], we may observe an increasing number of thesub-disciplines of the Earth (and related) sciences being included.This pattern could continue, as [13] allude to the possible futureinclusion of atmospheric particles as a tool in the forensic arena.

6. Soil forensics

This was first used to provide a name for a meeting (2006) inAustralia of that name, and has assumed a published status with[14]. Thus we see the circle completed, with the first named use [8]of soil in forensics some 40 years ago and the value of soil still at theheart of using Earth materials in criminal and related (e.g.environmental, humanitarian) investigations. As mentioned inSection 1, this is probably the most-widely known application ofEarth materials in forensic science, yet, apart from Brooks andNewton’s [8] use of forensic pedology, is the most recent to have aclear, tangible definition [14]. This is excellent, as it includes all themethods of geological, geoscientific and geoforensic analysis, butapplied to soil. Thus water, sediment and topography are notdirectly included. Pye [12] also used soil evidence in his title, asmany of the sophisticated methods of analysis he describes forsediments are applied very well to the inorganic as well (less so) tothe organic portions of soil.

7. Environmental forensics

The most eloquent definition of this name may be found in thejournal of the same name [18] and applies to all scientific studies ofthe environmental impact of human activities and natural

disasters. This most usually involves the impact of pollutants onthe environment and involves the Earth sciences where remotesensing is used to monitor vegetation, geophysics to define areas ofpollution, geochemistry to detect anomalous chemicals, amongstmany others. Debates concerning climate and sea-level change, aswell as the damage caused, will undoubtedly result in legal actionin the future, when this term will become even more widely used.

8. Discussion and summary

Specific applications of science or Earth science to forensics areeasier to define than the more general terms (above). If only onemethod or material is being discussed, then its use can be definedvery simply, examples being forensic geophysics, remote sensing,petrography or micropalaeontology. Far harder to define is the useof biological (non fossilised) materials in forensics, this being anessential part of the Earth systems discussed above, and includedin all of the terms discussed. However, the study of microbiological(spores, pollen, algae) and macrobiological (skeletal remains)materials is a far larger part of forensics than can be included in anyof the ‘geo’ or soil words, and thus will remain a complimentaryname such as ‘microbioforensics’. To summarise, this workprovides the following definitions for specialists and non-specialists alike to consider using, such that confusion may beavoided.

� Forensic pedology: the study of soil, both in situ as a naturalmaterial possibly disrupted by unusual events, or as a transferredmaterial on suspects, victims and associated items (tyres,vehicles).� Forensic geology: the use of geological methods and materials in

the analysis of samples and places that maybe connected withcriminal behaviour [9,10,19] or disasters. Geology in this senseencompasses geological methods of analysis (geophysics,petrography, geochemistry, microscopy, micropalaeontology).� Forensic geoscience: encompasses forensic geology and forensic

pedology, as well as unusual applications such as statistics andbedrock geology.� Geoforensics: encompasses forensic pedology, Geology, forensic

geoscience and includes geomorphology, GIS, remote sensing,human geography (including sociology) and geostatistics.� Soil forensics: includes all the methods available to study the use

of soil in forensics, meaning not only the study of soil (Pedology)but also the methods outlined in forensic geology, forensicgeoscience and geoforensics, as applied specifically to soil, asopposed to bedrock geology, for instance.� Environmental forensics: the use of any of the above methods, as

well as chemistry, biology, physics and the environmentalsciences in the assessment of environmental impact.

Acknowledgements

This article was inspired by discussions at two conferences.First with Peter Bull, Ruth Morgan and Duncan Pirrie at the 2009conference on Crime Science, where I presented some of theseideas with Laurance Donnelly, who is likewise thanked. Second atthe First Ibero-American Conference on Forensic Geology, wherediscussions with Carlos Martin Molina, Bill Schneck, RaymondMurray and again Laurance Donnelly were inspirational. A lot ofthe material mentioned above was derived from my works withJennifer McKinley, who is thanked.

References

[1] Scientific American, Science and art: curious use of the microscope, ScientificAmerican 11 (30) (1856) 240.

A. Ruffell / Forensic Science International 202 (2010) 9–1212

[2] A. Conan-Doyle, The Complete Sherlock Holmes, Doubleday & Company Inc., NewYork, 1930, 554 pp..

[3] H. Gross, Handbuch fur Untersuchungsrichter als Kriminalistik Criminal Investi-gation: A practical Textbook for Magistrates, Police Officers and Lawyers. Adam &Adam (1906) and Jackson (1962), Sweet & Maxwell, 1962.

[4] G. Popp, Bomben, Erdspuren un Instrumenten-untersuchung, Zeitschrift furoffentliche Chemie XXI (1910).

[5] G. Popp, Botanische Spuren und Mikroorganismen im kriminalverfahren, Archivfur Kriminologie XIV (1939) 231–237.

[6] E.B. Block, The Wizard of Berkeley, Coward-McCann, New York, 1958, 254 pp..[7] F.E. Camps, Soil—some medico-legal aspects, in: M.W. Neil, F.L. Warren (Eds.), Soil.

British Academy of Forensic Sciences Teaching Symposium No. 1, Sweet &Maxwell Ltd., London, 1962, pp. 47–51.

[8] M. Brooks, K. Newton, Forensic pedology, Police Journal (London) 42 (1969) 107–112.

[9] R. Murray, Evidence from the Earth, Mountain Press Publishing Co., Missoula,Montana, 2004, 226 pp..

[10] K. Pye, D. Croft (Eds.), Forensic Geoscience: Principles, Techniques and Applica-tions, vol. 232, Geological Society of London, 2004 318 pp. (Special Publication).

[11] R. Murray, J.C.F. Tedrow, Forensic Geology: Earth Sciences and Criminal Investi-gation, Rutgers University Press, New York, 1975, 240 pp. (republished 1986).

[12] K. Pye, Geological and Soil Evidence: Forensic Applications, CRC Press, 2007 335pp..

[13] A. Ruffell, J. McKinley, Geoforensics, Wiley-Blackwell, 2008 332 pp..[14] K. Ritz, L. Dawson, D. Miller, Criminal and Environmental Soil Forensics, Springer,

Amsterdam, 1910, 520 pp..[15] A. Ruffell, L.J. Donnelly, 2009. Geology and the search for human remains

(conference presentation, abstract at: http://www.crimescience.org/).[16] J. Thorwald, Crime and Science: The New Frontier in Criminology, Harcourt, Brace

& Co., San Diego, 1967.[17] A. Ruffell, J. McKinley, Forensic Geology & Geoscience, Earth Science Reviews 69

(2005) 235–247.[18] http://www.tandf.co.uk/journals/journal.asp?issn=1527-5922&linktype=5.[19] R. Murray, The geologist as private eye, Natural History (February) (1975) 22–24.