applied principles from geology and soil science · applied principles from geology and soil...

3

Applied Principles from Geology and Soil Science

1.1 Introduction

Soil micromorphologists now working in archaeology are potentially in a much bet-ter position than they were during the 1950s through to the 1980s (Cornwall, 1953 ; Courty et al., 1989 ; Limbrey, 1975 ; Romans and Robertson, 1975a , 1983b ). In fact, there has been a “spectacular increase” in the numbers of papers in archaeology (and paleopedology) toward the end of the last century (period analyzed spanned 1900– 2000; Stoops, 2014 ). Th is is in part the result of a continually accumulating database, as ever more sites employ soil micromorphology. Th is also refl ects the increasing numbers of workers and complementary techniques (e.g., micro- FTIR , EDS, microprobe), and publications in refereed journals and volumes in this fi eld. Other important stimuli to the more accurate employment of soil micromorphol-ogy are experiments, the collection of reference materials, and the development of a Working Group (in Archaeological Soil Micromorphology ) where both students and experienced workers interact. Th e International Working Group began with a small workshop at the Institute of Archaeology, University College, London in 1990, and has continued to the present day with meetings in 2013 at Cambridge (UK) and Basel (Switzerland ), and in 2014 at Amersfoort (Th e Netherlands) (Arpin et al., 1998 ; Macphail, 2014a , 2014c). It can be noted that a recent survey of Working Group attendees at a number of venues, and which included the testing of workers with a wide span of experience (from trainee students to senior researchers), found a common weakness in their background of geological training, presumably mainly due to students oft en having a dominantly archaeological developmental path (Ruth Shahack- Gross, Basel workshop 2013, pers. comm.) (Shahack- Gross, 2015 ). By con-trast, senior researchers more oft en had a training and postdoctoral involvement in earth sciences. Chiefl y, the Basel meeting concluded that workers need to develop

1

https://www.cambridge.org/core/terms. https://doi.org/10.1017/9780511895562.002Downloaded from https://www.cambridge.org/core. IP address: 54.39.106.173, on 21 Apr 2020 at 11:37:54, subject to the Cambridge Core terms of use, available at

https://www.cambridge.org/core/terms

https://doi.org/10.1017/9780511895562.002

https://www.cambridge.org/core

4 Background Approach and Methods

4

their understanding of the geological context of their sites as a fi rst step in any inves-tigation, hence one raison d’être for this book, and our previous work (Goldberg and Macphail, 2006b ).

Moreover, this application of soil micromorphology to archaeology (geoarchaeol-ogy), thus has its basis in the earth sciences, primarily soil science and geology. Th e former includes both fundamental soil science principles (Brady and Weil, 2008 ; Duchaufour, 1982 ) and developments in soil micromorphological description and the characterization of pedological and geomorphological processes, as recognized at the microscale (Bullock et al., 1985 ; Courty et al., 1989 ; Stoops, 2003 ; Stoops et al., 2010 ). It can be reiterated here, however, that many of the developments in the geo-archaeological study of anthropogenic soils and sediments has come from an experi-mental, reference, and site- study database (see Section 1.7 ). Associated investigations may also include soil science and geology, with the latter involving sedimentology, and igneous and metamorphic petrology, for example. Mineral petrology and iden-tifi cations (now oft en by X- ray spectrometry) is mainly a focus of ceramic prov-enancing and associated forensic investigations ( Pirrie et al., 2004 ; Quinn, 2013 ; Spataro, 2002 ). Th ere is, unfortunately, no room in this chapter to include a full geological and soil science background. Th is has already been achieved in previous volumes (Courty et al., 1989 ; Goldberg and Macphail, 2006b ). In this introductory chapter we have been forced to be extremely selective, but this is hopefully off set by the large number of reference sediment and soil types described and illustrated throughout this book, and the numerous specialized references that we have noted.

Th e chapter begins with an introduction to some sediment and rock types found in the book’s case studies, which are given alongside some of the sedimentary envi-ronments and associated geological/ geomorphological processes that are the most likely to be encountered by geoarchaeologists (see Table 1.1 , in which some studied sites are listed, and Chapter 5 where terrestrial – fl uvial , slope, and mass- movement – processes are described according to case studies). Th e important concepts of Facies and Microfacies are briefl y introduced alongside some sediment type examples of special concern in this book. Th e latter include calcareous formations and what are termed as Transitional Environments in Tables 1.2 and 1.3 . Soils and pedological processes are also only briefl y introduced alongside some site examples ( Table 1.4 ), because again numerous soil types are dealt with in detail in Chapter 4 . Other site examples from around the world are given throughout the book; for example, desert soils and paddy soils are viewed in the context of agriculture in Chapter 9 , while a tropical soil formation example is given in Chapter 12 . It is also important to note that soil micromorphologists working in archaeology are no longer totally reliant



https://doi.org/10.1017/9780511895562.002


5Applied Principles from Geolo gy and Soil Science

5

Table 1.1. Common sedimentary environments and their subdivisions and site examples found in this book

Marine environments Transitional environments Continental environments

Open shelves Lagoons and bays (Boxgrove, UK;

Guantanomo Bay, Cuba; Playa Vista, USA)

Mountain ranges (Chisone Valley, Italy)

Sheltered shelves (Ommels Hoveo,

Denmark)

Deltas (Playa Vista, USA; Oslo,

Norway)

Intermontane (Pratto Mollo and Uscio,

Italy; Upland Norway, Sweden, England and Wales)

Inland seas (Oslo Fjord, Norway)

Beaches (Marco Gonzalez, Belize;

Guantanomo Bay, Cuba; Boxgrove, UK; Gibraltar caves)

Troughs (Olduvai Gorge,

Tanzania)

Continental slopes Mangrove swamps (Marco Gonzalez, Belize)

Deserts (Cactus Hill, Dona Ana

and Las Capas, USA; Negev Desert, Israel)

Pelagic oceans (Also tidal fl ats, sand bars, estuaries, saltmarsh) (Blackwater, Crouch, Humber, Severn and Th ames Rivers; Wallasea Island, Essex, UK; Marco Gonzalez, Belize)

River valleys (Imjin and Hantan Rivers,

Korea; Liujian River, Hui zui, China; River Lågan, Norway; Eden, Humber, Itchen, Nene, Th ames Rivers, UK)

Deep- water trenches Lakes and ponds (Bargone, Italy;

Berkhampstead, Boxgrove, UK)

Coral reefs (Marco Gonzalez, Belize)

Alluvial plains (Ecsegfalva, Hungary;

Magura and Borduşani, Romania)

Coastal plains (Djibouti)

Source : Modifi ed from Kukal, 1971; Reineck and Singh, 1986 and as employed in Courty et al. (1989).



https://doi.org/10.1017/9780511895562.002



6

Table 1.2. Calcium carbonate (CaCO 3 ) formations, features, and inclusions

Type Common environment of formation

Common characteristics and comments

Travertine 1 Calcareous springs, lake edges

Oft en bedded, composed of calcite crystals – used for construction (e.g., Herodian aqueduct, Jordan Valley)

Tufa 2 Calcareous springs, rivers Porous, mixture of micritic and microsparitic calcite, with embedded fi ne to coarse plant fragments – used for construction (easily split for wall and fl oor slabs)

Marl 3 Ponds, lakes, and lagoons (and marine)

Generic term for impure calcium carbonate (~35%– 65%), which may contain silt, sand, and clay (~35%– 65%); calcareous microfossils can also be present (molluscs, charophyte [green algae] remains, ostracods).

Calcrete 4 Terrestrial soils and sediments

Massive cementation of soils and regoliths by groundwater rich in dissolved CaCO 3

Speleothem 5 Caves, karstic caves Stalactites (hanging down), stalagmites (growing upward), dripstone and moonmilk (biochemically formed on cave walls); cemented cave breccias.

Biogenic calcite A 6 Soils and sediments Calcite root cell pseudomorphs (rhizoliths), needle fi bers (pseudomycelia) and other biogenic structures formed in calcareous environments. Such phenomena can occur in decalcifi ed soils if roots penetrate through to an underlying calcareous substrate/ groundwater.



https://doi.org/10.1017/9780511895562.002



7

on geology and soil science to help them understand sites, as was the case in the 1980s. Th is is because of the major and continuing development of experimental and reference databases (see 1.7– 8; see also Chapter 7 ). Th e origins and breadth of these is introduced, while relevant examples are given in detail for instance in Chapters 4 (eff ects of soil burial), 9 (ancient cultivation ), and 10 – 11 (use of space and animal husbandry). Lastly, while numerous textbooks cover fi eld work and sampling, this book focuses on the various strategies and tactics applied to various site types, from Quaternary sites to those of complex societies (1.9).

Type Common environment of formation

Common characteristics and comments

Biogenic calcite B 7 Plant and faunal remains Calcite (altered calcium oxalate) residues in leaf, root, and wood (charcoal) remains; herbivore dung spherulites; ashes and recemented ashes, slug (Arionid) plates, earthworm granules, land snails, freshwater and marine molluscs; microfossils such as ostracods and some foraminifera.

1: Courty et al., 1989 , 99– 100; Goldberg and Macphail, 2006, 24– 26 2: Courty et al., 1989 , 99– 100; Goldberg and Macphail, 2006, 24– 26 3: Pettijohn, 1975 4: Courty et al., 1989 , 174– 179; Durand et al., 2010 5: Courty et al., 1989 , 99– 100; Gillieson, 1996 6: Becze- Deák et al., 1997; Durand et al., 2010 7: Brochier, 1996 ; Brochier and Th inon, 2003 ; Brochier et al., 1992 ; Canti, 1998a ,

1999 ; Canti, 1998b ; Durand et al., 2010 ; Karkanas et al., 2007 ; Shahack- Gross, 2010 ; Shahack- Gross et al., 2014

Table 1.2. (cont.)



https://doi.org/10.1017/9780511895562.002


8

Table 1.3. Coastal environments

Environment Sediment type Character Comments

High energy cliff base and wave cut platform

Boulders derived from cliff rock and/ or boulders within cliff (e.g., conglomerates, till)

E.g.: interstitial, massive and laminated coarse and very coarse sands, gravel and cobbles; sometimes calcitic with shell fragments.

Relict deposits can be decalcifi ed with laminae picked out by iron- panning; may occur as cemented conglomerates.

High energy beach zone

Cobbles, gravel, and sands

Generally well- sorted fi ne or medium or coarse sands in swash zone; very coarse sands, gravels, and cobbles at top of beach.

E.g: coarsely bedded well- sorted fi ne sands with bands of micritic clay- size material (detrital chalk) with very high interference colors (only 3– 4% clay in decalcifi ed samples). Chalk fossils, chalk fragments present; Coarse (2– 3 to 20– 30mm) burrows (polychaete worms and molluscs); micro- faulting. (Boxgrove, West Sussex, UK)

Inundation beach (Marco Gonzalez, Belize) (Note, intense bioworking leads to massive

structured “poorly sorted” mixed sands and clay- size material)

(Guantanomo Bay beach, Cuba)Coastal dune area Cross- bedded and

massive sandsWell- rounded and well- sorted

sands; shell fragmentsWhen occurring in coastal caves, can be

interdigitated with silty clay of terrestrial phreatic origin (Vanguard Cave, Gibraltar)

Low energy estuarine mudfl at and lagoonal environments

Silts and clays; marls; sometimes with organic content

Finely laminated silts and clays, massive to fi nely laminated marls

(Secondary minerals can include gypsum, jarosite, pyrite, and siderite)

Horizontally laminated; can include “coarse” (fi ne sand) along with silt and clay laminae, some of which are rich in detrital organic matter. (Marco Gonzalez, Belize; Guantanomo Bay lagoon, Cuba; Th e Stumble, River Blackwater and Stanford Wharf, River Th ames, Essex, UK, and Boxgrove, West Sussex, UK)

Unweathered sediments can be calcitic, and sometimes lagoonal marls form (Playa Vista, USA).

Saltmarsh, mangrove, and other swampland

Silts and clays (“muds”); commonly with organic content.

Oft en massive, but with relict laminae at depth below bioworking level.

(see above for possible secondary minerals)

Fresh deposits are likely to be calcitic, laminated, and with detrital organic matter content; local plant remains (marsh, swamp plants, and invasive woodland possible); probable freshwater fl ushing, ripening eff ects, and secondary mineral formations, alongside bioworking features (Wallasea Island, River Crouch, Stamford Wharf, River Th ames and Goldcliff , River Severn, UK)

Note : See Table 6.3 for post- depositional eff ects on inundated sites and soils. Source : Aft er Goldberg, 1979; Goldberg and Macphail, 2006; Reineck and Singh, 1986 .

https://doi.org/10.1017/9780511895562.002D

ownloaded from

https://ww

w.cam

bridge.org/core. IP address: 54.39.106.173, on 21 Apr 2020 at 11:37:54, subject to the Cambridge Core term

s of use, available at https://ww

w.cam

bridge.org/core/terms.

https://doi.org/10.1017/9780511895562.002




10

Table 1.4. Soil horizons, soil types, and studied examples

Common usage horizon/ soil type (FAO, UK and USA)

Soil character (aft er Goldberg and Macphail, 2006, table 3.2 )

Studied example

L (Litter)/ Oi/ O1/ Mull topsoil (cf. Mollic epipedon and Umbric epipedon)

and LF (Fermentation)/

Oe/ O2/ Moder topsoil (essentially well- drained

conditions)

(L) High biological activity; only accumulation of plant fragments.

(F) Moderately low biological activity; accumulation of excrements of soil fauna and decomposing plant fragments below L.

Overton Down (Grassland Rendzina) and Wareham (Heathland Podzol) Experimental Earthworks, UK

Bagböle Experimental Farm, North Sweden (Boreal Podzol)

Marco Gonzalez, Belize (Tropical woodland surface soil)

Laminated mull ( Barrat, 1964 )

(essentially poorly drained conditions)

(L- F) Interlayered, oft en horizontally oriented plant remains (e.g., grass, sedge) and patchy invertebrate mesofauna excrements.

Gleyed coastal topsoils at Viking Gokstad Ship Burial Mound, Norway and Wallasea Island Experiment, UK; Roman Hadrian’s (turf) Wall, UK

LFH (Mor “humus”) ~Oa/ O2

(H) Very low biological activity (e.g., bacteria); accumulation of amorphous organic matter termed humus (H) below, L and F.

Neolithic Stonehenge Quarry, Bronze Age West Heath (Heathland Podzol), Early Iron Age Hengistbury Head (Oak podzol), Bronze Age Fan Foel and Dark Age “Short Dykes” Powys (Upland grassland), UK

Peat/ ~Oa)/ O/ (Histic epipedon)

(O) Absolute accumulation of organic matter because waterlogging inhibits biological breakdown of organic matter.

Middle Pleistocene (Boxgrove) and Holocene (Goldcliff ) coastal peats, fen and fen carr peats (Innova Park, Pilgrims, Sutton Gault, Th ames Crossings), UK; Pratto Mollo basin and Bargone lake peat, Italy.



https://doi.org/10.1017/9780511895562.002



11



Studied example

Humic topsoil (A1h) (Mollic epipedon and Umbric epipedon; Mollisols include grassland prairie soils and chernozems)

(A) Accumulation of organic matter in the mineral soil (along with associated nutrients of N, K, and P); focus of biological activity and organic matter turnover (oxidation and alteration – “fermentation” leads to maghemite iron and enhanced magnetic susceptibility)

See Mull; Neolithic Belle Tout, Easton Down, Hazleton, Maiden Castle, Windmill Hill, UK; Ecsegfalva, Hungary

Plaggen “Ap” (Cultosol) Anthropic epidpedon

Over- thickened (0.40– 1.0 m) humic topsoil developed through additions of manure, turf, household and settlement waste. (e.g., since AD 1000 in Holland)

Roman Wittington Ave, medieval Whitefriars, UK; Iron Age Bjornstad, Hørdalsåsen, etc., Norway; early medieval Tours, France; Chisone Valley, Italy

Ap Ploughsoil/ Cultivated A/ Arable topsoil

Topsoil, mechanically homogenized to depth of plough share ( c . 0.40 m) or ard (e.g., 0.06 m); liable to loss of organic matter through oxidation; arable soils ameliorated by additions of organic manures, possibly since Neolithic.

Experimental Butser (UK) and Bagböle (Sweden) Farms, and modern Hazleton and Wallasea Island; Neolithic Easton Down, Hazleton and Kilham, Bronze Age Ashcombe Bottom and Phoenix Wharf, Roman Whitefriars, Saxon Oakley, Medieval Wolverhampton, modern Wallasea Island, UK; Viking Lindholm Høje, Denmark; Early medieval Büraburg, Germany; Iron Age- Viking Avaldsnes and Hesby, Norway

Table 1.4. (cont.)

(continued)



https://doi.org/10.1017/9780511895562.002



12



Studied example

A1h Pasture topsoil/ ~prairie/ cf Mollic epipedon (Ap; includes both plough and pasture in USA)

Normally grass covered humic topsoil (cf Mull), with crumb over fi ne blocky microstructure; surface compaction, dung traces possible.

Modern Maiden Castle, Neolithic Belle Tout, Neolithic and Bronze Age Raunds, UK; Bronze/ Iron Age Avaldsnes and Fevang nordre, Norway

Eb/ Leached/ eluviated upper subsoil horizon / Albic E (A2)(Argillic Brown Soil/ Luvisol/ Alfi sol)

Specifi cally eluviation of clay (along with cations, including iron; organic matter and phosphorus)

Prehistoric to Roman London and Whitefriars, Neolithic to Iron Age Raunds, UK; Huizui, China

Ea (Eag – when surface waterlogging)/ Leached/ eluviated upper subsoil horizon/ Albic E (A2)(Podzol/ Spodosol)

Eluviation of iron and aluminum (sesquioxides) (aft er acid breakdown of clay and mobilization by plant chelates)

Experimental Wareham, Bronze Age Chysauster, Hengistbury Head, West Heath, Dark Age Short Dykes, Wales; Hørdalsåsen, Norway

Bw subsoil horizon/ Cambic B (Brown Soil/ Cambisol)

General pedogenic alteration as indicated by weathering of minerals, structure formation, loss of carbonates, and clay formation, etc.

Neolithic Carn Brea

Argillic Bt subsoil horizon/ Argillic B (Argillic brown soil/ Luvisol/ Alfi sol)

As above, but with illuviation of clay from overlying A2 horizon (clay translocation)

Neolithic to Bronze Age Raunds, Prehistoric to Roman London and Whitefriars, UK; Huizui, China; Borduşani, Romania

Bs/ Bh/ Bhs subsoil horizon/ Spodic B (Podzol/ Spodosol)

Illuviation of sesquioxides (Fe and Al) oft en with humus

Experimental Wareham, Neolithic Carn Brea, Bronze Age Chysauster, Hengistbury Head, West Heath, UK; Hørdalsåsen, Norway

Table 1.4. (cont.)



https://doi.org/10.1017/9780511895562.002



13



Studied example

Calcic B and K horizons/ Alkaline Bk/

Calcic and Petrocalcic (Calrete / Calcisols / aridosols)

Illuviation of alkaline earths, especially calcium carbonate; cementation by calcium carbonate (K horizon/ calcrete)

Beach rock, Gibraltar (see text for “marl” and

“tufa;” Table 1.2 )

Gypsic horizon/ gypsic By (In acid- sulphate soils/ in

Kastonozems/ Gypsid)

Concentration/ cementation by gypsum

Marine and intertidal examples – Goldcliff , Essex and Th ames, UK; Oslo Fjord (see Table 1.3 )

Gleyed (Ag, Bg, G) topsoil and subsoil horizons/ Gleyic G (Bg)(Sometimes with Albic and below Peat) (Gleys/ Gleysols/ Aquents, Aquepts)

Gleying or hydromorphic process of reducing iron (Fe 3+ to Fe 2+ ; Mn 4+ to Mn 2+ ); pale (G) and mottled (Bg) colors.

Dark Age Short Dykes, Wales; Neolithic Carlisle and Peterborough, Bronze- Iron Age Humber coast and Innova Park, Th ames Crossing, Turing College; Huizui, China; Gokstad Heimdaljordet, and Gudbrandsdalen and Hesby, Norway; Magura, Romania

Colluvium (Colluvial B horizon)/ Cumulic

(fi ne hillwash/ unsorted colluvium)

Fine (<2mm) to unsorted (>2mm) stony downslope accumulations and/ or soil- sediments (see Chapter 6 ); if waterlaid can retain microlaminated microstructure.

Ashcombe Bottom, Bourne Valley, Boxgrove, Brean Down, Dartford Crossing, White Horse Stone, Stawberry Hill, UK; Huizui, China; Büraburg, Germany; Gudbrandsdalen and Hesby, Norway

Note : See Chapters 4 , 5 , 6 , and 9 ; Goldberg and Macphail, 2006, table 3.2 .

Table 1.4. (cont.)



https://doi.org/10.1017/9780511895562.002



14

1.2 Sediment Types and Geological Processes

In archaeology we mainly deal with soft sediments, unconsolidated rocks and rego-liths (alluvium , beach sands, intertidal muds, talus), some of which can be cemented (“beach rock,” tufa ). In addition, “hard” igneous and metamorphic rocks may form the substrate to a site (e.g., Bargone , Italy ), be used for grind stones, or simply form part of the background rock fragment and mineral suite. For example, basalt may form in situ lava beds (Chongokni ; see Plate VIIa ) or simply be part of the clas-tic composition of a sediment. Mineralogists, when studying loose samples, divide minerals based on their specifi c gravity. “Light” minerals (<2.0 specifi c gravity ), such as quartz, quartzite, feldspar, and mica, are common residual silicate minerals (see Table 3.4 ). Other minerals with a greater (>2.0) specifi c gravity, including “heavy” minerals (>4.5), may occur where there is an igneous rock background for example, and iron minerals such as magnetite (s.g.=~5.2) may be present as gravity concentra-tions in fl uvial sediments (e.g., Djibouti ; Plates IIa and IIc ). Such magnetite concen-trations can aff ect background magnetic susceptibility readings, for example along the E18 highway route near Larvik, Vestfold, southern Norway where the Larvikite formation contains magnetite. As this intrusive igneous rock type also includes apa-tite (calcium phosphate ), interpretations of soil phosphate measurement also had to take this into consideration (Viklund et al., 2013 ). In addition, some “igneous” rock minerals also occur as neo formed silicate minerals in iron slag , for example fayalite (iron silicate), because of the high temperature involved in iron manufacture (see Chapter 7 ). Another heavy mineral is cassiterite (tin ore; s.g.=~7.0), which can also be found in gravity concentrations – placer deposits. In southern England and other areas of sedimentary Cretaceous geology there are Greensand Beds, which include glauconite , a greenish- colored iron silicate mineral that weathers into a brown iron- stained grain, and which is ubiquitous in regional alluvial and periglacial sedi-ments ( Loveland, 1981 ; Loveland and Findlay, 1982 ). It is also found within chalk, a relatively soft limestone. Th us, at least a rudimentary knowledge of rock types – sedimentary, igneous, and metamorphic – and associated minerals is important background information for any site study. Not only will these infl uence local soils, drainage, relief, and geomorphological processes, but can be a source of raw materi-als for building and industry.

It was stated in Courty et al. ( 1989 ) that geologists oft en group sediments on genetic criteria, into four broad and sometimes overlapping groups, namely: detrital (or clastic) sediments, chemical (or non- clastic) sediments, organic deposits, and pyroclastic deposits.



https://doi.org/10.1017/9780511895562.002



15

• Detrital sediments are those consisting of a variety of solid materials (minerals, rock fragments, organic constituents) that have been deposited by one or more agencies of transport, such as water, wind, or gravity. Examples include aeolian sand, fl uvia-tile gravel, and lacustrine clay; cited case studies include paleochannel and shallow water marine (harbor) sediments (see Box 1.1 , Figures 1.1 – 1.6 ; Plates Ia and VIIIb ).

Box 1.1: Marine Harbor Sedimentation in Oslo Fjord , Norway ; the fourteenth- century “B13” Wreck Excavation; Figures 1.2– 1.7

Th e B13 medieval shipwreck in Oslo harbor was investigated employing eighteen thin sections (sediment micromorphology and EDS) and forty- seven bulk samples (LOI, fractionated P, and magnetic susceptibility); four particle size analyses were also carried out (Macphail and Linderholm, 2013). Th e ship has a dendrochrono-logical date of aft er AD 1353, with a hardwood fragment within the sediments hav-ing calibrated 2- sigma dates of 1330– 1340 and 1400– 1440 (J. Bill, Cultural History Museum, Oslo, pers. comm.) ( Figure 1.2 ). Generally, marine estuarine, fully under-water, anaerobic, low energy silt loam to silty clay loam sedimentation took place. Sediments are poorly to moderately humic (~3– 8.6% LOI), contain 440– 620 ppm P 2 O 5 and generally have a low magnetic susceptibility. It can also be noted that some of the lowest deposits (– 1.454 m asl) record diff use silty clay laminae and also high amounts of muddy sediment inwash in places. Th ese probably record initial muddy intertidal “mudfl at”- like infi lling of the wreck and the eff ects of bioturbation on these sediments during their accumulation. Th e ship was possibly “beached” on this “mudfl at.” Radiocarbon dating of wood and bark within these basal sediments clearly indicate infi lling of the wreck with already in- place, and “older” in situ sedi-ments. It is also worth noting here that fi ne voids and likely associated detrital plant remains have become infi lled with pyrite framboids and/ or pyritized, respectively; pyrite formation occurred within wood fragments ( Figures 1.3 – 1.6 ). Pyrite (FeS 2 ) is good evidence of anaerobic conditions.

In general, sedimentation was strongly characterized by detrital organic matter deposition, including probably much seaweed (bladder wrack tentatively identi-fi ed) (marine macrofossils were also recovered) ( Figure 1.7 ). Upward, macrofossil analysis (plants and shells) indicate a change from dominant sea water to one also infl uenced by freshwater inputs (J. Linderholm, pers. comm.). Fully underwater low energy sedimentation was apparently recorded below and above the wreck. Very fi ne to large (~40 mm) wood, bark, and charcoal fragments are concentrated



https://doi.org/10.1017/9780511895562.002



16

• Chemical and biochemical sediments are those formed by precipitation from solution, with or without the assistance of microorganisms such as algae, and compose such items as speleothem deposits (e.g., stalagmites), travertine and tufa , evaporitic minerals associated with arid lakes and salt pans (nitrates, sul-fates, chlorides), limestone and chalcedony (chert, fl int, and jasper) (some calcitic examples are listed in Table 1.2 ).

• Organic deposits contain a high proportion of remains of living organisms (shells, plant tissues) and are represented by shelly beach deposits and carbonaceous deposits, such as peat (e.g., Bargone “lake,” Italy and Pilgrim’s School “paleochan-nel,” Winchester).

• Pyroclastic deposits are composed of fragments of various sizes resulting from explosive volcanic eruptions: volcanic bombs, lapilli, and shards of volcanic ash (at Pompeii , this includes both road- fi lls and the mineral component of soils; Figure 1.1 ).

in some layers (see Figure 1.3 ). Wood fragments show a variety of preservation characteristics, from almost total decay (only knotwood remains), “brown-ing,” original pyrite impregnation and later pyrite depletion and iron staining, for example. Some cambium cells are still rarely present in places between bark and wood and may show earlier fl y larvae infestation (Paul and Phil Buckland, pers. comm); some cellulose is both birefringent and autofl uorescent under blue light. Suggested intertidal exposure of the wreck seems to have led to increased bioworking (with very fi ne wood splinters sometimes being later redeposited in microlaminated sediments). Upward, as more freshwater inputs were inferred from macrofossil recovery, some subaerial weathering (“sediment ripening”) occurred. Th is led to pyrite depletion, general iron depletion and concomitant iron staining (hypocoatings), as oxygen penetrated the sediments.

In comparison, for the preliminary studies of the nearby >20 m deep Sørenga borehole within the area of Medieval Oslo (D1A, 234/ 102, “Alna River location”), the lowest sediments show very little porosity (~5% voids). Th is lack of poros-ity in these similarly weakly humic silty clay loam sediments is exacerbated by voids and detrital plant fragments being infi lled with pyrite or being pyritized. Some partially pyrite- infi lled voids were latterly totally infi lled with gypsum (see 205– 209, Huisman et al., 2009 ). Shell may be a source of calcium carbon-ate in the formation of gypsum (CaSO 4 ). Some shallow water sediments were found at anomalously deep depths, probably due to slumping typical of fj ords (J. Linderholm, pers. comm.).



https://doi.org/10.1017/9780511895562.002



17

Band og hudbord stikker ut fra profilvegg i ØV-retning.

Pâlemarkspisttreverk. Resteretter band.

Mikromorfprover

MikromorfproverKjølsvin

Spunt-vegg

1T595Hoydeverdl = –0.22m

Lag 4

Lag 2

Lag 3

Lag 1

Hudbord

1T594Hoydeverdi= –0.21 m

Ødelagtav masking

Ødelagtav masking

Ødelagt av maskingP4

pT7pT7P18P18

P19P19

P20P20

P21P21

pT6pT6

pT5pT5

pT4pT4

pT3pT3

P5

P6

P7

P8

P9

P10

P11

P12

Bark 1210–1290

Profil 3C550N

Dendro date; after AD1353 Wood (Picea) 1215–1280

pT7P18

P19

P20

P21

pT6

pT5

pT4

pT3

Figure 1.2 Oslo, Norway: fourteenth- century B13 shipwreck remains within estuarine silt loam to silty clay loam sediments within Oslo’s medieval harbor. Soil micromor-phology (“Mikromorfprover”) and bulk sample sequences from the ship’s wooden keel upward. Ship dendrochronology date of aft er 1353; bark and wood fragments also dated from sediments (e.g., AD 1215– 1280 and 1210– 1290). Illustration from Engen and Bill (2015).

Figure 1.1 Pompeii, Italy; AD 79 eruption by Vesuvius buried the Roman town. Photomicrograph of layered volcanic ash infi lling a road; the original airborne sediment, of mainly fi ne to medium sand- size (max. 0.1 mm) volcanic glass (tephra), black clinker, igneous rock minerals, igneous and limestone rock clasts, also shows a compact layer in the upper part of the image – probably as a result of being partially waterlaid. Plane-polarized light (PPL). Scale bar = 0.5 mm.



https://doi.org/10.1017/9780511895562.002



18

It was also stated that any and all of these sediments were deposited as a result of processes acting in a certain sedimentary environment, and that the terms “sedi-mentary processes” and “sedimentary environments” are overlapping concepts that have been much used by geologists. A number of common sedimentary envi-ronments have been recognized. Th ese are Marine, Transitional, and Continental environments. Th ese are listed in Table 1.1 , together with some site examples pre-sented in this book. Most site studies are located in Continental environments, and few are truly Marine in character, such as Oslo Fjord (see Box 1.1 ), and for example one site (Ommels Hoveo, Denmark ) is in fact a fully inundated land sur-face due to post- glacial “inland sea” formation in the North Sea (Doggerland) and shallow seas within the Danish archipelago ( Skaarup and Grøn, 2004b ). Since the publication of the original book in 1989, there has been a major development in the study of Transitional Environments ( sensu lato Intertidal Zone ), and informa-tion on these can be found in Table 1.3 ( Bell et al., 2000 ; Wilkinson et al., 2012b ). In addition, the whole of Chapter 6 focuses on this environment type. Some coastal caves also include information on past shoreline dynamics; for instance, Gibraltar and South Africa ( Goldberg, 2000b ; Goldberg and Macphail, 2012 ; Macphail et al., 2012b ), as well as Continental ones (Berna et al., 2012 ; Goldberg et al., 2001 , 2009b ; Shahack- Gross et al., 2008a ; Weiner et al., 1995 ). Although Continental sites are

Figure 1.4 As Figure 1.2 , photomicrograph of M3270C; coarse decaying wood frag-ments (W) and example of bark (B). Note dark iron- staining of wood. Wood in some lower layers where anaerobic condi-tions persist, are character-ized by pyrite framboids. Scale bar = 10 mm.

Figure 1.3 As Figure 1.2 , digital fl atbed scan of M3219A; diff usely bedded silty clay loam, with “dark” pyrite framboid concen-trations (arrows), evident of typical mud-fl at sedimentation, with possible gravity concentrations. Scale bar = 10 mm.



https://doi.org/10.1017/9780511895562.002



19

1

MgNa

FeO

Ca

K

AISi

S

KK

Ca

Ca

Fe

Fe

2 3 4 5 6 7keV

Spectrum 1

Full Scale 2287 cts Cursor: 0.000

Figure 1.6 As Figure 1.2 , X- ray EDS Spectrum of pyrite framboid cluster; note pyrite (FeS 2 ) with 21.4 percent Fe and 27.2 percent S.

300 μm

Spectrum 1

Pyrite

Electron Image 1

Figure 1.5 As Figure 1.2 , X- ray backscatter image of sediment containing pyrite fram-boid clusters (see Figure 1.5 for Spectrum 1). Scale = 300 μm.

the most numerous in this book, many other examples have been best studied by others, e.g., lake occupations (Ismail- Meyer and Rentzel, 2004 ; Ismail- Meyer et al., 2013 ), and several Quaternary sites and occupations ( Courty, 2001 , 2012 ; Courty and Vallverdu, 2001 ; Fedoroff et al., 1990 , 2010a ; Mallol and Carbonell i Roura, 2007 ).



https://doi.org/10.1017/9780511895562.002



20

We continue to adopt the viewpoint that “a sedimentary environment is defi ned by a particular set of physical and chemical parameters that correspond to a geo-morphic unit of stated size and shape” (Pettijohn et al., 1973: 450). It was once thought that marine environments gave little potential for archaeological soil micromorphological study, but with some transitional environments this is no longer the case. In fact, it is surprising how many “transitional environments” have come under scrutiny in relationship to human occupation, especially when major climatic shift s occurred aff ecting sea level, for example, at Boxgrove (UK) during the Middle Pleistocene , and much of North- West Europe’s low- lying ground and coastline during the early Holocene Period was subjected to marine inundation ( Chapter 6 ; see Table 6.3 ). Sites that are currently under water can be accessed at low tide, or if deeply buried or in deeper water, can be accessed by borehole studies or by excavations using coff erdams. In the shallow sea around Langelands Island, Denmark , Mesolithic sites and associated woodland environments are preserved ( Skaarup and Grøn, 2004a ), and a core at Ommels Hoveo found a relict soil layer rich in microartifacts, such as bone, fi re- cracked fl int, other burned rock, burned shell and fused ash, relict of a hearth. On the other side of the coin, it also has to be remembered that Holocene warming led to post- glacial uplift as ice sheets melted, and transitional (marine) environments became terrestrial, as recorded for exam-ple, in Maine, USA and Scandinavia (Kelley et al., 2010 ; Macphail et al., 2013a ;

Figure 1.7 As Figure 1.2 , photomicrograph of 3270A; example of seaweed (SW: bladder wrack), with fi ne charcoal and iron staining boundary (Fe), indicative of subaerial weather-ing eff ects. PPL, scale bar = 1 mm.



https://doi.org/10.1017/9780511895562.002



21

Sørensen et al., 2007a ). In the latter case, post- glacial uplift has led to many coastal (beach and fj ord) sediments now being located far inland, well above sea level, with altitude (m asl – meters above sea level) being a dating proxy; Early to Late Mesolithic sites range between 90 and 250 m asl, currently in northern Sweden (J. Linderholm, Umeå University, pers. comm.). Later in this book, Viking coastal sites, such as Heimdaljordet and Gokstad Ship Burial Mound, Vestfold, Norway , are discussed (e.g., Chapter 11 ), which are now several kilometers inland of the modern (ex- whaling) port of Sandefj ord. Here, land uplift has simply occurred (cf. Kaupang ; Sørensen et al., 2007a ), and for example parcel ditch fi lls, rich in marine diatom death assemblages, were left high and dry. By contrast, at the top of Oslo Fjord , marine sediments have been accumulating since prehistory, and for example sealed a late Medieval wooden shipwreck . Th is shipwreck excavation, and more recent borehole studies of Oslo harbor sediments, have also involved multidisciplinary investigations, and these have produced some basic fi ndings of note ( Box 1.1 ). For example, important secondary minerals, such as gypsum , pyrite, and jarosite found in intertidal environments, were noted; their occurrence is dis-cussed in more detail in Chapter 6 (see Huisman, 2009 ; Kooistra, 1978 ; Wiltshire et al., 1994).

Many coastal middens and midden- like occupation deposits have been investi-gated in detail ( Goldberg, 2000b ; Stein, 1992 ; Villagran et al., 2009 ). Beach sands are an unstable substrate and experimental studies have shown how artifacts can be dispersed by trampling in such sediments ( Barton, 1992 : 78– 95). Anthropogenic material produced by ephemeral occupations may therefore only be found as dis-persed fi ne material, such as charcoal and burned shell.

Within a Continental alluvial environment there are a number of depositional microenvironments with their own specifi c conditions and depositional pro-cesses, varying from high energy channel deposits (sands and gravels) to lower energy seasonal fl ood plain sediments (silts and clay), while “marine beach” can include sands, gravels, and cobbles . As long recognized in pre- Quaternary geol-ogy ( Wright, 1986 ), but perhaps less realized in Holocene deposits, the world is not static.

1.3 Facies and Microfacies

These terms are broadly presented and discussed in Goldberg and Macphail (2006, 38– 39) as useful and vital concepts in geoarchaeology. From the soil



https://doi.org/10.1017/9780511895562.002



22

micromorphological point of view, a number of authors across Europe (at least) have suggested where the term “microfacies ” was first applied to an archaeo-logical site, but as any geoarchaeologist worth their salt would have been using this concept in any case, naming the first author(s) to do this seems to be rather an arid enquiry. In geology, it is understood that under similar environments of deposition similar deposits will be formed ( Hatch and Rastall, 1965 ; Reineck and Singh, 1986 ). Two independent variables affect this, which classically are divided into:

• Physical environment dominating the location of deposition – marine, deltaic, estuarine , aeolian (see Table 1.1 ), and

• Th e nature of the sedimentary material – clay, sands, gravels, fossiliferous, non- fossiliferous (see Chapter 2 ).

Under certain sets of conditions a specifi c sediment type is formed. A facies is the term employed to suggest the sum result of the “lithological and palaeontological characteristics exhibited by a deposit” (Hatch and Rastal, 1965 : 20).

In terms of archaeological applications the term “lithofacies” was utilized by Gilbertson ( Gilbertson, 1995 ) in a review of “Studies of lithostratigraphy and lithofa-cies: a selective review of research developments in the last decade and their applica-tions to geoarchaeology.” Archaeological soil and sediment micromorphology give a special emphasis to the study of microfacies , especially when trying to reconstruct human activity in a landscape or in use- of- space studies. In fact, a review of her own use of this concept and specifi c employment of “microfacies” was undertaken by Marie- Agnès Courty ( Courty, 2001 ). In her view ( Courty 2001 , 229) “– the ulti-mate goal of archaeological facies analysis is to restore the three- dimensional image of a human- related space at a given time and to describe its evolution.” Th e means to characterize “microfacies” in soil micromorphology description, with or without complementary data, and the practical application of this concept is presented in Chapter 3 .

Th us, the aforesaid defi nition is a slightly diff erent reading/ employment of the term “facies” to that used in geology which denotes a deposit or sediment that formed under similar environmental conditions and is composed of similar min-eralogical and organic (and fossil) components ( Hatch and Rastall, 1965 ). Reineck and Singh (1986 ) in fact focus on “depositional sedimentary environments .” In either case, there may be diff erent types of marine muds, some in the intertidal zone and some in deeper water, and they may well have diff erent fossils associated



https://doi.org/10.1017/9780511895562.002



23

with these varying environments. On the other hand, a soil scientist identifi es a given “soil series ” as one where the same pedological processes have acted on the same parent material to produce a similar soil cover. In archaeology, we are also dealing with accumulated midden and fl oor deposits, dumps and constructions, for example. We therefore have to have a pragmatic approach to terms employed in geology and pedology which we borrow. For instance, some of London ’s dark earth could be described as an unsorted clastic sediment or “diamict/ diamicton” (geology), or “cumulic calcareous brown earth” (pedology). Neither helps provide a totally satisfactory interpretation of the past use of urban space. It is therefore necessary to study an archaeological deposit like dark earth in a variety of mutu-ally supportive ways. Broadly (See Section 1.9 for more details) it can be studied in terms of its:

1. Field character, including thickness, areal extent, association with other archae-ological features (walls, ditches) and dating, and

2. Soil micromorphology (microstratigraphy ), including Coarse Components, Fine Fabric , and Pedofeatures. Th e last, giving insights into weathering and other post- depositional processes which resulted in an “unsorted sediment” forming a “cumulic calcareous brown earth” (see Chapter 12 for applied dark earth investigations).

On the other hand, the coarse components and fi ne fabric can be studied in order to understand the cultural aspects of the site formation processes . 1: A near- dwelling archaeological context, and coarse inclusions dominated by charcoal , burned bone and a fi ne fabric that is ashy may imply that a dark earth fi rst accu-mulated through kitchen hearth waste disposal. 2: By contrast, structural remains, and a deposit containing earth- and lime - based building materials may suggest dark earth developed in a collapsed building shell. In both examples, a calcitic (~calcareous) “crystallitic” microfabric would be present, but in example 1, this would be formed of relict ash crystals and recrystallized calcite from weathered ash, while in the second example, the calcitic fi ne fabrics are likely to be derived from the weathering of lime- based plasters and mortar. Th us, as seen under the microscope, two microfacies types (termed MFTs – Goldberg and Macphail, 2006: 355– 356, 396– 402) would be diff erentiated employing both microfabric and coarse inclusion information, in order to comprehend the diff erent site formation pro-cesses involved in these two dark earth deposits. Th ese would still be classed as two diff erent MFTs even if the pedofeatures characterizing them were the same,



https://doi.org/10.1017/9780511895562.002



24

i.e., in the form of decalcifi cation , secondary calcite formation, and bioturbation, for example, because all aspects of the deposits need to be considered. Th is is dis-cussed more in Chapter 3 and in the various examples of site reconstruction given in the rest of the book.

Th e analysis of the fi ne fabric / microfabric (“Groundmass ”: Bullock et al., 1985 : 88; Stoops, 2003 : 91) is given special emphasis in this book, because it is so oft en ignored by students, when in fact should be given as much emphasis as any coarse compo-nent or pedofeature. Th is fi ne fabric can be a binder in a plaster or mud brick , form the “fi ne earth” in a soil horizon, or provide the groundmass in an anthropogenic layer. Th rough petrological analysis these can be characterized and diff erentiated in SMTs ( Soil/ Sediment Microfabric Types ; Chapter 3 ).

1.4 Examples of Sedimentary Geology

For the purposes of this book, Tables 1.1 and 1.– 3 gives some examples of a num-ber of marine and associated transitional environments and what microfacies have been identifi ed in them (Goldberg and Macphail, 2006b ; Reineck and Singh, 1986 ). As transitional environments are so important to coastal and marine archaeology, especially given the modern day threat to coastal sites from sea level rise, the eff ects of rising base levels, fresh and salt water inundation have been given extra attention in later sections (e.g., Chapters 5 and 6, Table 6.3 ) ( Macphail et al., 2010 ). One of the chief case studies of this volume is the Middle Pleistocene , Lower Palaeolithic site of Boxgrove (West Sussex, UK), where sediments vary between (1) marine beach sands, lagoonal/ tidal fl at and probable salt marsh silts and clays, and (2) terrestrial freshwater pond , low energy silt loam brickearths, path gravels, and unsorted soli-fl uction head deposit ( Table 5.2 ; see Plate Ib ). Th ese are the sequences that are asso-ciated with dramatic changes (and fl uctuations) in climate and sea level ( Roberts and Parfi tt, 1999 ). Importantly, chipping fl oors were identifi ed on (1) ephemeral surfaces formed on tidal fl ats, (2) short- lived ripened soil- sediments, and (3) cool climate solifl uction soil- sediments. Th ese sediment type characterizations are con-sistent with both micro- and macro fossil identifi cations (animal and hominid bones, foraminifera, mollusca, nanofossils, pollen ) (Roberts et al., Forthcoming; Roberts et al., 1994 ). Th ese studies also usefully illustrate a commonly asked ques-tion: are we dealing with a sediment or a soil? As discussed in much detail later in Chapter 5 concerning “soil- sediments” (e.g., Fedoroff et al., 2010a ; Fedoroff and Goldberg, 1982 ), forcing a microfacies type into a sediment “box” or soil “box” is



https://doi.org/10.1017/9780511895562.002



25

counterproductive, incorrect, and can be a waste of descriptive and analytical data. At Boxgrove , laminated beach sands and intertidal silts and clays, once- humic salt marsh sediments, pond marls, brickearth , path gravels and solifl uction deposits are all sediments, but some can show ripening / weathering and biological eff ects of soil formation. Another example of this can occur in wetlands where hydroseral sequences occur as sites undergo drying out as woodland takes over from grasses, sedges, and reeds for example, and peat and included macrofossils are converted into a terrestrial moder humus for example (see Chapter 5 : Pilgrim’s School , River Itchen, Winchester, UK, and Stainton West, Cumbria, UK). Also within the River Itchen alluvial sediments there were examples of tufa formation, where springs pre-cipitated calcium carbonate derived from local chalk bedrock and calcareous river gravels.

1.4.1 Calcium Carbonate Features and Inclusions

In addition to tufa , this kind of secondary calcareous formation can also occur as massive travertine , which diff ers from soft er, more porous tufa which oft en embeds plant material (Courty et al., 1989 : 98– 99) ( Table 1.2 ). Speleothem formation in caves as stalagmites, stalactites, and dripstone features are also very important secondary calcium carbonate (CaCO 3 ) phenomena, sometimes cementing occupation deposits for example ( Gillieson, 1996 ; Goldberg and Macphail, 2006: 177– 178) (see Chapter 8 ). Th e Middle Pleistocene Red and Yellow Breccias found at the cave of Westbury- sub- Mendip , Mendip Hills, Somerset, UK, are discussed in Chapter 8 , in relationship to karstic cave sediment formation in environments associated with bird and animal occupation ( Andrews, 1990 ; Macphail and Goldberg, 1999 ). Descriptions of calcite are presented in Chapter 3 .

In northwest Europe, there are many instances of late glacial- early Holocene calcium carbonate formation, which at the cave of Arene Candide (Liguria, Italy ) formed a cemented breccia containing Epipalaeolithic materials, while at Th ree Ways Wharf (Uxbridge, UK) the early Mesolithic levels were sealed in places by a tufa (Lewis et al., 1992 ; Macphail et al., 1994). An early Holocene lake marl was encountered at Westhampnett , West Sussex, UK; a humic Allerød soil merged upward into this impure, minerogenic calcium carbonate sediment) (Lewis et al., 1992 ; Lewis and Racham, 2011; Macphail, 2008c ) (see also Chapter 5 ). Specifi cally in regard to such sediment types when viewed as “archaeological materials ” ( Chapter 7 ), it should be noted that tufa can also be an important building material,



https://doi.org/10.1017/9780511895562.002



26

although used diff erently from limestone- like travertine . For example, it has been used as walling slabs in timber framed buildings dating to at least the medie-val period in the Cevennes , France . Th is is because it is so light in weight, being much more porous compared to travertine. Th e clear identifi cation and diff eren-tiation of tufa from lime plaster is highly important therefore. A case in point is given in Chapter 7 from Huizui , Henan Province, China , where Yangshao (Middle Neolithic ) occupations in the loess plateau region included “white fl oors” (Liu et al., 2002 – 2004 ) (see Plates Ic– e ). An original fi eld and laboratory interpreta-tion of these as lime plaster fl oors was contradicted by the soil micromorpholog-ical and chemical identifi cation of these as tufa slabs; a lime plaster identifi cation could not be justifi ed aft er this study (Macphail and Crowther, 2007c). A chief clue was the presence of “blackened” (not charred) plant fragments embedded within the tufa, which had been quarried as slabs.

Other examples of (1) tufa and tufa- like formations and (2) marls occur:

1. As tufa embedding basalt tools at the Olduvai Gorge sites, Tanzania, Africa ( Plate IId ) and spring- fed carbonate-rich humic Rendzina soil- sediments at Upper Palaeolithic Kostenki, Russia and palaeochannel deposits along the River Itchen, Winchester – Pilgrim’s School ( Holliday et al., 2007 ), and

2. marl sediments at Middle Pleistocene Boxgrove (freshwater ponds utilized by animals and hominins); early Holocene Westhampnett (lake marl); ancient and historic Playa Vista , California, USA (coastal lagoon marl; Goldberg and Macphail, 2006a ),

are detailed in Chapters 5 and 8 . Calcium carbonate (and calcitic materials) also makes up important calcitic

pedofeatures in soils and sediments (e.g., root pseudomorphs , cemented calcrete ), as well as being present as faunal remains (e.g., earthworm granules , mollusk shells), and as the minerogenic residues of plants (e.g., calcium oxalates and as transformed into calcite, cemented hearth ash) and herbivore dung (“dung spherulites ”) (Durand et al., 2010 ) ( Table 1.2 ; see Plates IIIc– f and XIh ). At the same time, pedological processes which give rise to a variety of soils and soil horizon types ( Table 1.4 ), include both the formation of calcitic features and the decarbonation of calcareous soils and rocks (Courty et al., 1989 : 172– 174; Duchaufour, 1982 ). Although there can be acid rain from dissolved atmospheric sulphur dioxide (forming sulphuric acid) from industrial and volcanic activity that aff ects soils and buildings, we shall mainly discuss here the eff ects of weak carbonic acid ( H 2 CO 3 ) formed from the mixing of



https://doi.org/10.1017/9780511895562.002



27

rainwater with dissolved atmospheric CO 2 . Precipitation and dissolution of calcium carbonate is expressed as:

CaCO 3 + CO 2 + H2O ↔ Ca 2+ + H 2 CO 3 , and in the archaeological and conservation sciences, this means that lime plasters and mortars , as well as calcareous rock constructions are prone to such weathering attacks. Plant acids also play a part, whether these are from soil humus, plant roots, and/ or cya-nobacteria ( Straulino et al., 2013 ). Th e combined eff ects of such weathering are dealt with in terms of European dark earth formation and specifi cally weathering of Maya lime- based structures at Marco Gonzalez , Belize in Chapter 12 – “Site Transformation ” (see models in Macphail, 1994; Goldberg and Macphail, 2006: 271– 273).

1.5 Coastal and Terrestrial Soil- Sediments Examples

Some examples of coastal environments and associated sediments are given in Table 1.3 . Such soil- sediments forming in “transitional” environments are dealt with in full detail in Chapters 5 and 6.

1.6 Soils

Archaeological sites and materials are subject to post- depositional processes , and these include soil formation processes. A previous publication has dealt with these processes in detail (Courty et al., 1989 : 138– 189). Many of the microfeatures formed by these processes have been extensively illustrated by various authors in Stoops et al. ( 2010 ), but unlike the Courty et al. ( 1989 ) publication, there are few case studies from archaeological sites. Some soil types and horizons are listed in Table 1.4 , as previously published in Goldberg and Macphail (2006) (see Plates Via- b , Xa- d , and XIa- b ). Th ere have been further changes to soil classifi cation since then, but on the basis that the actual soils and processes involved in their formation have not altered, it seems reasonable not to further update this table to any great extent. Classifi cation of soils will continue to develop and change in any case even aft er this volume is published. Table 1.4 is therefore only given for guidance alongside a list of relevant exemplars, as this book focuses on archaeo-logical soils and sediments and their associated site formation processes . In fact, Chapter 4 (“Soils and Burial”) provides a series of examples of soil types and their associated edaphic conditions, albeit only from the northern hemisphere,



https://doi.org/10.1017/9780511895562.002



28

where vegetation and land use interpretations are based upon micropedological features, standard bulk analyses, and paleoenvironmental studies, when available. More importantly, all are from archaeological sites and many have been buried, with the eff ects of burial being monitored for some types by classic archaeological experiments (Earthworks Project ; see Section 1.7 ). In addition, each of the chap-ters in Parts II – IV discusses relevant post- depositional processes, and how they can cause “noise” – especially in Pleistocene sites – for example, and alter both the buried constituents and the nature of the microfabric itself (see also Huisman, 2009 ). Chapter 12 focuses on post- depositional processes from a number of envi-ronments including tropical Belize , and also discusses human activities as part of this reworking process.

1.7 Soils and Experiments, Including Archaeological Reconstructions and History of Research

One way we have as scientists to understand the timescales involved in pedo-genic and site formation processes is through analog studies and experiments. For example, the deposition of loess , the stability of loess soils under forest and arable impact have been studied systematically in Europe ( Imeson et al., 1980 ; Kwaad and Mücher, 1977 , 1979 ; Mücher and de Ploey, 1977 ). Other experiments have been car-ried out in order to address specifi c questions in archaeology – the eff ects of burial, how to recognize cultivation, and how to identify use- of- space from occupation deposits. Most information on ancient “natural” soils has come from soil profi les buried by the construction of monuments or by the deposition of sediments, such as alluvium . In the fi rst case, many of the early soil investigations (e.g., by Ian Cornwall in the UK; reviewed in Macphail, 1987 ), were paralleled by environmen-tal studies of land snails on calcareous substrates ( Carter, 1987 ; Evans, 1972 ) and pollen on acid soils ( Davidson et al., 1999 ; Dimbleby, 1962 ; Dimbleby and Evans, 1974 ; Sageidet, 2005 ). In order to understand better the eff ects of burial on base rich and acid soils, two Experimental Earthworks were constructed in the UK, at Overton Down , Wiltshire (Rendzinas on chalk ; see Plate V ) and at Wareham , Hampshire (Podzols on Tertiary sands) ( Bell et al., 1996 ; Crowther et al., 1996 ; Evans and Limbrey, 1974 ; Macphail et al., 2003a ). Results are detailed in Chapter 4 . Th e study of ancient tillage benefi ted from studies in modern agronomy ( Collins and Larney, 1987 ; Jongerius, 1970 , 1983 ; Kooistra, 1987 ). Moreover, the eff ects of cultivation at “ancient farms ” and experimental plots has been recorded for exam-ple from:



https://doi.org/10.1017/9780511895562.002



29

• “Iron and Romano- British” Butser Ancient Farms , Hampshire, UK on calcareous colluvium , rendzinas and argillic brown earths (see Plate If ),

• “Prehistoric and historic” Bagböle , Umeå, north Sweden on Boreal podzols , • “Neolithic ” ard ploughing at Hambacher Forest , Rhinelands, Germany on loess

(luvisols), • “Viking” ploughing at the Lehre Experiment, Denmark , • Clearance, slash and burn cultivation on broadleaved woodland forest soils

(luvisols) on loess covered Triassic geology on the Hohenlohe Plain, southwest Germany (Th e Forchtenberg- Experiment ), and

• Ard ploughing of diff erent soil mixtures at Rothamsted Experimental Institute, Harpenden, Hertfordshire, UK ( Banerjea et al., 2015 ; Gebhardt, 1990 , 1992 , 1995 ; Lewis, 1998; Lewis, 2012 ; Macphail, 1998 ; Macphail et al., 1990 ; Schulz et al., 2011 ) (see Chapter 9 ).

Data on anthropogenic deposits has also been gathered from experimental settle-ments and ethnoarchaeological studies ( Banerjea et al., 2015 ; Friesem et al., 2011 ; Friesem et al., 2014b ; Macphail et al., 2006a ; Macphail et al., 2004 ; Mallol et al., 2013a ; Mallol et al., 2007 ; Matthews et al., 2000 ; Milek, 2006 ; Shahack- Gross et al., 2009 ; Shahack- Gross et al., 2003 ; Wattez, 1992 ) (see Chapters 7 , 10 , 11, and 12 ). Th ese new and exciting fi ndings are dealt with thematically in detail in Part III , in the context of archaeological soil and sediment studies. It is clear, however, that when ancient soils are compared to their modern counterparts, post- depositional pro-cesses , for example general ageing of soil organic matter need careful consideration before they can be directly equated. For example, at Hazelton the Neolithic long cairn- buried topsoil has 0.8– 1.22% Org C (n=5) (midden area: Org C=1.06– 1.47%). Th is can be compared to the amount of organic matter (Org C) in the local present day cultivated soil profi le (Ap: 3.48%; B1: 2.18%; B2: 0.89%). In the same way, cal-careous sediments (e.g., Boxgrove Units 4b and 4c) and occupation deposits that were once ash- rich (Ecsegfalva , Hungary ; “dark earth ”), can become strongly decal-cifi ed due to post- depositional subaerial weathering , losing both the detail of their microstratigraphy and bulk, becoming much thinner as a consequence (possibly up to 40% loss of bulk). As already noted, such post- depositional pedological and geo-genic processes were detailed in Courty et al. ( 1989 ); where relevant these eff ects are included in the case studies presented in subsequent chapters. Th is includes “phosphatization ” (pp. 186– 189). Studied examples include the formation of the Yellow Breccia in the Middle Pleistocene cave of Westbury- sub- Mendip , Somerset, Upper Palaeolithic levels in the Arene Candide rock shelter, Liguria, Italy , the exper-imental stabling fl oor at Butser Ancient Farm, and numerous instances of calcium



https://doi.org/10.1017/9780511895562.002



30

phosphate contamination of occupation sediments ( Macphail and Goldberg, 1999 ; Macphail et al., 1994, 2004). Such autofl uorescent features show up during scanning of thin sections under blue light (see Chapters 2 – 3 ).

1.8 Reference Materials and Their Study

Whereas geology and soil science had well established reference collections and numerous published “atlases” of diff erent rock types and soft sediments ( Adams et al., 1984 ; Reineck and Singh, 1986 ), and soil microfabrics formed by numerous processes were presented in numerous journals and Proceedings of the International Working Meetings on Soil Micromorphology, for example (Bullock and Murphy , 1983 ; Fedoroff et al., 1987 ), no such reference collection existed during the 1970s and 1980s for archaeological soil micromorphology. Th e three authors of Soils and Micromorphology in Archaeology (1989) therefore had to develop their own refer-ence collections (see Chapter 7 ). Th ese were formed by:

• the analysis of numerous reference materials found on archaeological sites (e.g., dog coprolite at Iron Age , Maiden Castle , UK; Neolithic burned daub at Ecsegfalva , Hungary ),

• the specifi c collection of excrements, including that of hyena , at Tel-Aviv Zoo , Israel , and domestic animal dung at Butser Ancient Farm ,

• experimental soils and sediments as found at Butser Ancient Farm (including domestic and stabling fl oor deposits), in a pig pen at West Stow Anglo- Saxon Village , Suff olk, and as formed by deliberate marine inundation at Wallasea Island , Essex (see Plates If , VIII , VIIIc– d and Xe– g ), and

• well-studied archaeological soils and deposits, which produced “type” materi-als, varying from Roman lead droplets (Free School Lane , Leicester; Plate XIVg ), burned eggshell in fl oor deposits (Early Medieval London Guildhall), human mineralized cess (Norman Monkton ), uncharred hazel nut and broadleaved tree buds (Mesolithic Stainton West, Carlisle ; Plates IVa– b ), iron and phosphate - stained byre waste of woody browse origin (Prehistoric E18 , Norway ), layer cake cave sediments composed of ashed woody fodder stabling origin (Neolithic Arene Candide , Italy ), Palaeolithic bedding (Middle Stone Age Sibudu Cave ) and tin ore – cassiterite (Bronze Age Bodmin Moor ), for example.

Such “archaeological materials ,” or microartifacts and microfacies types were sum-marized by Macphail and Goldberg (Goldberg and Macphail, 2006b ; Macphail and



https://doi.org/10.1017/9780511895562.002



31

Goldberg, 2010 ), with special deposits being recorded in various publications, for instance (Goldberg et al., 2009b ; Macphail et al., 2010 ; Macphail and Crowther, 2011a ; Macphail et al., 2004 ). Many others have produced experimental and analog results (Friesem et al., 2010, 2014a, 2014b; Gé et al., 1993 ; Karkanas, 2007 ; Karkanas and Goldberg, 2010 ; Matthews, 2005 ; Rentzel and Narten, 2000 ; Shahack- Gross, 2010 ). Co- workers have also produced thematic sections in recently published Encyclopaedias (Encyclopaedia of Geoarchaeology and Encyclopaedia of Global Archaeology), while a multi- authored “Archaeological Soil and Sediment Micromorphology,” initiated by K . Milek is currently in press (Nicosia and Stoops , In press/ 2017). In many cases now, soil micromorpholog-ical description ( Chapter 3 ) is complemented by other analyses ( Chapter 2 ), to aid the interpretational process. Th ese methods include both associated bulk sample analyses employing standard techniques (both from soil science and geology, and methods spe-cifi cally designed for geoarchaeology – fractionated phosphate and magnetic susceptibil-ity including both qualitative and maximum potential MS), and specialized techniques, such as XRF (X- ray fl uorescence) , XRD (X- ray diff raction) , and organic chemistry . Th ere are also numerous instrumental techniques which can be applied directly to the thin section (EDS , microprobe, and micro- FTIR ). Microfacies analyses may well also include associated microfossil (e.g., pollen , foraminifera ) and macrofossil studies.

1.9 Fieldwork, Sampling and Laboratory Processing

Most aspects of fi eld work and sampling strategies have been elucidated already (Courty et al., 1989 ; Goldberg and Macphail, 2003 , 2006b ), and in order to save space, this section focuses on methods applied to some of the case studies employed in this book. More detail on sampling for micromorphology combined with micro-fossil and bulk soil analyses are given in Chapter 2 (see also Figures 5.4 – 5.5 ).

Although aft er the stone and sediment make up had been removed at Hazleton long cairn, Gloucestershire, exposing sections through it, none of the Neolithic soil was sectioned. To create sondages through the buried soil, small pits were excavated. Th ese in fact produced a number of Mesolithic artifacts. In the end, some fi ve cairn sections were sampled, including “midden” and tree- throw areas (see Plate Xa ). Quarry fi lls and local (“control”) profi les were also included in the palaeoenviron-mental study carried out with Martin Bell (currently Reading University) that also included an auger survey across the site as a whole ( Bell and Macphail, 1990 ; Saville, 1990 ). Soil micromorphology, chemistry, and grain size analyses chiefl y focused on understanding buried soil taphonomy, identifying buried soil areas of grassland, arable, and Atlantic Period tree- throw; the charcoal - rich midden area also seem to



https://doi.org/10.1017/9780511895562.002



32

have had a cultivation history ( Macphail, 1990 a). A similar team approach was car-ried out on sections and features at Brean Down , Somerset from the most recent historic soils, down through Bronze and Iron Age occupation and coastal dune sequences, and others made an auger survey ( Bell, 1990 ). Quaternary palaeosols were re- investigated employing Dr Ian Cornwall ’s thin section collection (Institute of Archaeology, University College London ), alongside new samples through Beaker cultivation colluvium and dune sequences, Bronze Age hut fl oors made of estua-rine “clay,” hearths, and salt working layers (Macphail, 1990 d). Bulk analyses also included magnetic susceptibility studies as a joint investigation with soil chemistry ( Allen and Macphail, 1987 ). A similar approach was carried out at Uscio , a Castellaro in Liguria, Italy . Th e soil study at Maiden Castle , Dorset also followed a similar pat-tern of studying Neolithic, and Early and Late Iron Age “bank barrow” and rampart buried soils , respectively. But, in addition, a full sequence of Early Iron Age discard deposits was investigated from one of the deep ditches, at the base of which water-laid silty clay “silting” sediments were found ( Macphail, 1991 ).

In all the above listed sites, sampling had to focus on available excavated sections, which did not always allow for lateral control samples, although modern soil exam-ples were compared to their ancient counterparts at Hazleton , Uscio , Maiden Castle , for example. Th is can be a problem when sites have been very thoroughly “excavated” in the past, as for example at cave sites. Much of the study of the semi- continuous ver-tical sequences from diff erent areas, and their lateral control samples of the Holocene (“stabling “) deposits in Arene Candide rock shelter, Finale Ligure, had to be carried out on “testimony baulks,” while mainly only sondages penetrated the Palaeolithic levels ( Courty et al., 1991 ; Macphail et al., 1994 , 1997; Maggi, 1997 ). Ten areas already excavated by Bernabò Brea, Cardini, and Gandolfi , were targeted by some forty- nine mammoth thin sections, for example. More studies are continuing ( Maggi and Nisbet, 2000 ; Rellini et al., 2013 ). Similarly, at Gough’s Cave , Cheddar, very little Late Pleistocene sediment had been preserved by the Victorian entrepreneurs, whereas at Westbury- sub- Mendip Cave, quarrying had left Middle Pleistocene sediments that were very diffi cult to access. Both sites, however, contributed to important integrated palaeoenvironmental reconstructions by the Natural History Museum, London (Andrews et al., 1999 ; Macphail and Goldberg, 1999 , 2003 ; Stringer, 2000 ).

Boxgrove and Chongokni In contrast, the Lower Palaeolithic and Middle Pleistocene site of Boxgrove and Late Pleistocene Chongokni (Korea ) off ered a series of blank canvases (see Chapters 5 , 6, and 8; Plates Ib and VIIa– b ). Choosing the right sampling strategy and focusing on specifi c locations within the sequences to mitigate the eff ects of Pleistocene “noise” (i.e., usually dominating natural geomorphologi-cal and pedological site formation process in outdoor sites) that generally obscures



https://doi.org/10.1017/9780511895562.002



33

attempts to pinpoint human activity and the exactly contemporary environment (see Figure 5.16a and Plates Ib and VIIa ). Eight meters of Late Pleistocene sediments had accumulated over a lava fl ow at Chongokni , Hantan River, Korea ( Yi, 2005 ). Sediments containing Acheulian - like hand axes ( Yi, 1988 ) were studied employing a semi- continuous thin section sequence. In addition, a series of thin section samples were carefully taken from below rare cobble- size stones, including artifacts such as a hand axe and a core , which hypothetically off ered some protection.

Similarly at Boxgrove , although numerous small and large quarry exposures along a 900 m- long site were variously sampled, including both single monoliths to semi- continuous sequences, some samples were taken specifi cally through artifact scatters. Th is allowed numerous variants of the marine- continental/ temperate- cool climate sediments to be studied in the fi rst few seasons alone, employing fi ft y- two thin sec-tions, which were collected from nineteen areas. Particle size , organic carbon , calcium carbonate analyses, and EDS studies were also carried out, to complement a system-atic heavy mineral and sedimentological study by John Catt ( Catt, 1999 ; Macphail, 1999a ). Areas of refi tting Acheulian artifacts associated with hand axe manufacture and butchery sites were specially targeted. In order to make sure the thin section actually recorded such “chipping” fl oors , Mark Roberts inserted Kubiena boxes into artifact- rich sediments as the only way to be sure any “surfaces” could be studied – a lateral sample was just not good enough when such an important investigation was required to help reconstruct the occupied landscape. A major macrofossil study examining faunal remains, including those of Homo heidelbergensis , was also under-taken ( Roberts and Parfi tt, 1999 ; Roberts et al., 1994 ). A <100 m size “waterhole” area of marl- like sediments which contained two hominid teeth and a tibia came under renewed scrutiny and where the tibia location was intensively sampled (other “water-hole” samples including its margins were also part of the study). In addition to a series of individual samples (46 x 80– 130 mm- long thin sections) across the base of the waterhole fi ll and which focused on a number of specifi c features and concentra-tions of artifacts, and the tibia and teeth locations themselves, a control profi le near the tibia site was taken. Th is control profi le comprised two lengths of 0.40 m- long plastic downpipe creating a continuous 0.80 m- long “sample.” Th is was for soil and sediment micromorphology study. It was exactly paralleled by another 0.80 m- long plastic downpipe “sample” for bulk analyses . Th e fi rst sample was resin- embedded for thin section manufacture (8 ~130 mm- long thin sections) while the second was subsampled for bulk samples ( n =44 taken every 10– 20 mm). Th e types of bulk anal-yses and use of complementary methods such as Image Analysis and Microprobe , are detailed in the next chapter . Equally, at the Tower of London moat , 0.40 m- long monoliths were employed to provide a continuous thin section and bulk sample



https://doi.org/10.1017/9780511895562.002



34

sequence through the moat sediments that dated from the thirteenth century to when it was drained in the nineteenth century ( Keevill, 2004 ). Both Kubiena tin - and long plastic downpipe - sampling have been used to investigate colluvia and intertidal sedi-ments, for example. In the latter case, safety is a very important issue with deep mud, quicksand, and rapidly advancing tides being dangers ( Bell et al., 2000 : 11). In the UK, sites are accessed at low tide, with the lowest tides being chosen to reach experimen-tally fl ooded grassland at Wallasea Island , Essex and in order to have enough time to excavate pits and take samples (see Chapter 6 ).

Subsequent to the open quarry studies at Boxgrove a series of boreholes were taken across this part of West Sussex Coastal Plain and showed that the coastal embayment associated with Lower Palaeolithic occupation extended to some 25 km in width. One key junction is between Units 4c (Old Land Surface – see Table 8.1 ) and 5a (Iron pan – coastal peat – see Table 5.1 ) and selected ~110mm- wide cores were split and one half used to make a series of 75 mm long, 50 mm wide thin sections across this boundary. One core , BH5, found the best and thickest example of the Unit 4c– 5a junction, and was studied employing four thin sections and associated bulk samples (see Chapter 6 ; Macphail et al., 2010 ; Roberts and Pope, in press/ 2017). Other examples of borehole studies employed in this book are from the Gokstad Ship Burial Mound, Norway (see below: Gokstad Ship Burial Mound) and Pilgrim’s School, Winchester. At the latter, the core was split between bulk samples for bulk soil analyses, radiocarbon dating and pollen sequences, and parallel thin section studies (Macphail et al., 2009 ).

At Chongokni , on the River Hantan , Korea , eight meters of Late Pleistocene sedi-ments had accumulated over a lava fl ow ( Yi, 2005 ) ( Chapter 5 ). Sediments contained Acheulian - like hand axes ( Yi, 1988 ), and were studied employing a semi- continuous thin section sequence. As similar sediments had been studied previously from the Hantan and Imjin River sites, and much confusing Quaternary “noise” was expected. A series of thin section samples were carefully taken from below rare cobble- size stones, including artifacts such as a hand axe and a core , which hypothetically off ered some protection. Th e reader can fi nd out how successful this was in Chapters 5 and 8 .

Gokstad Ship Burial Mound Here, at a Norwegian cultural icon site, the only way to properly investigate the mound makeup and its Viking setting was through coring, in order that only ~2 percent disturbance was caused ( Figures 1.8 – 1.10 ). Th is was in part related to earlier excavations (1880, 1902, 1928– 1929, and 2007), espe-cially of the center, but also including the removal of the well- preserved Viking long-ship now housed at the Viking Museum, Oslo (Cannell, 2012; Macphail et al., 2013a ; Nicolaysen, 1882 ). One complication to overcome was the backfi lling and landscap-ing that was carried out aft er previous excavations. Th e investigation involved eight



https://doi.org/10.1017/9780511895562.002



35

Figure 1.8 Gokstad Ship Burial Mound, near Sandefj ord, Vestfold, Norway: motor cor-ing was carried out along transects across the mound, fi rst using a spiral core to approxi-mately record the makeup of the mound and underlying and surrounding soils and geology, and secondly to take meter- long cores – here, from the sloping side of the mound (fi eld-work by Jan Bill, Rebecca Cannell, Marianne Hem Erikson, and Richard Macphail).

Figure 1.9 Location maps of Gokstad Mound and the nearby Viking coastal settlement of Heimdaljordet (Heimdal), which are located on the outskirts of Sandefj ord, between the Norwegian coastal towns of Larvik and Tønsberg. Th e Gokstad Viking long ship was recov-ered from the Gokstad Mound, while the equally famous Oseberg long ship was found near Tønsberg. Both are now housed in the Viking Museum, Oslo (Macphail et al., 2013 , Figure 1).



https://doi.org/10.1017/9780511895562.002



36

transects across and into the mound with a spiral core , in order to describe and log the underlying sediments and deposits making up the mound, before deciding upon where to take undisturbed “cylinder” cores for analysis. Cylinder cores subsequently focused on examples of the thickest parts of the mound and their varied make up, pos-sible locations of the tenth-century robber and earliest excavation trenches, and the

Figure 1.10 Gokstad Ship Burial Mound: Location of spiral coring (SP) and extracted cyl-inder cores (CY), showing central area of ship burial and 1880 excavation (now backfi lled). Examples of cores mentioned in the text: clockwise – North East Quadrant CY3: location of turf mound and buried soil/ intertidal sediment/ till sequence, and hypothetical access point to ship burial during its AD 900 construction; CY15: turf mound; beetles in poorly drained “laminated mull” turves; South East Quadrant CY18 and CY21: sample sequence through tenth century robber trench; South West Quadrant CY9: sampled location of 1880 trench; CY1: turf mound; examples of sedge grassland pollen in poorly drained “laminated mull” turves; North West Quadrant CY8: wood chip layer in lower turf mound. (Figure aft er Cannell, 2012).



https://doi.org/10.1017/9780511895562.002



37

one area of seemingly intact old ground surface. Th e cylinder cores were then stored under cool and dark conditions. Th e selected 75mm- wide cores were then opened in a laboratory at the Cultural History Museum, University of Oslo, where the cores were described and logged (in part through employing a magnetic susceptibility meter), before being cut longitudinally for thin section and bulk sample studies. Th e still intact bulk sample half of the cores were then re- examined at the Environmental Archaeology Laboratory (MAL), University of Umeå, and then horizontally sliced for combined bulk geoarchaeological (LOI, P, and magnetic susceptibility), pollen and macrofossils studies, that perfectly correlated with the layers being studied in thin section. Broad fi ndings included palaeoenviromental reconstructions dating to post- glacial land emergence ~700 BC and the AD 900 Viking landscape (from buried soil and turf mound materials), mound constructional methods for example as related to ship preservation, and the eff ects of the tenth-century break- in trench ( Bill and Daly, 2012 ; Cannell, 2012; Linderholm et al., 2013; Macphail et al., 2013a ).

Complex societies Th e sampling strategies applied to famous settlement sites such as Lattes in southern France and Çatalhöyük , Turkey , and tells in general, have been well- documented ( Cammas, 1994 ; Courty, 2001 ; Matthews et al., 1996 , 1998 , 2000 ; Shahack- Gross et al., 2005 ). An example of a Romanian tell study is given later ( Box 11.1 ), and here monoliths were partially cut out using a hand- held motor saw. Other settlement types have also been sampled in ways to both cover the in situ settlement and its surrounds, one example being the Arbon/ Bleiche 3 Neolithic Swiss lake village (Ismail- Meyer and Rentzel, 2004 ; Ismail- Meyer et al., 2013 ). As is discussed in Chapter 11 , few large scale excavations that investi-gate a settlement as a whole rarely take place. Oft en excavations are in confi ned spaces, especially in urban archaeology, but here the small studied areas can be used to understand the settlement makeup as a whole as more and more excava-tions take place. Th is has also been true of dark earth studies, even though these superfi cially compare badly as an information source to the well- preserved strat-ifi ed archaeology found below (~Roman ) and above (~medieval). Now it is estab-lished that sampling also needs to focus on the dark earth for the very reason that these represent gaps in our urban history, even while recording occupation sometimes by large populations (see Chapter 12 ) ( Galinié, 2004 ; Galinié et al., 2007 ; Macphail et al., 2003b ). At the London Guildhall site Roman buried soils , the Arena and late Roman deposits, dark earth, early medieval and later medieval features were all studied. Aft er numerous samples were archived this still led to the analysis of fi ft y thin sections, and fi ft y- one bulk samples and thirty- one pol-len samples.



https://doi.org/10.1017/9780511895562.002



38

1.10 Conclusions

Th is chapter has introduced some of the geological and soil science principles employed in archaeological soil micromorphology, and outlines how the subject and techniques of archaeological soil micromorphology developed by both the eff orts of individuals and through a Working Group within the International Union of Soil Sciences. Although it is true that archaeological soil micromorphology was fi rst based upon soil and geological research it soon became clear that it had to construct its own database, employing archaeological reference materials, well stud-ied archaeological sediments, and experimental analogs. As described in Chapter 2 , many of the advances in archaeological soil micromorphology come from the use of complementary techniques analyzing background fossil assemblages and physical and chemical properties ( www.geoarchaeology.info/ asma ). In addition, a number of instrumental techniques can now be employed on the thin sections themselves.



https://doi.org/10.1017/9780511895562.002


applied principles from geology and soil science · applied principles from geology and soil...

Documents