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Reid, C. 1892 The Pleistocene deposits of the Sussex coast, and their equivalents
in other districts. Quarterly Journal of the Geological Society 48, 344365.
Seaward, D.R. 1982 Sea Area Atlas of the marine molluscs of Britain and Ireland.
Nature Conservancy Council, Shrewsbury.
Seaward. D.R. 1990Distribution of the marine molluscs of north west Europe.
Nature Conservancy Council, Peterborough, 114 pp.
Sparks, B.W. 1961 The ecological interpretation of Quaternary non-marineMollusca.Proceedings of the Linnean Society of London 172, 7180.
Stace, C. 1997 New Flora of the British Isles. 2nd edition. Cambridge University
Press, Cambridge 1130 pp.
Stinton, F. 1985. British Quaternary sh otoliths.Proceedings of the Geologists
Association 96, 199215.
Tebble, N. 1966British Bivalve Seashells. Royal Scottish Museum, Edinburgh,
212 pp.
West, R.G. 1980 Pleistocene forest history in East Anglia.New Phytologist 85,
571622.
West, R.G. and Sparks, B.W. 1960. Coastal interglacial deposits of the EnglishChannel.Philosophical Transactions of the Royal Society of London B306,
95133.
West, R.G., R.J.N. Devoy, B.M. Funnell, and J.E. Robinson. 1984. Pleistocene
deposits at Earnley, Bracklesham Bay, Sussex.Philosophical Transactions of
the Royal Society of London B 306, 137157.
Whatley, R.C. & Kaye, P. 1971. The palaeoecology of Eemian (Last Interglacial)
Ostracoda from Selsey, Sussex. In: Oertli, H.J. (ed.), Colloque sur la
Palocologie des Ostracodes, Pau 1970. Bulletin de Centre de Recherches
Pau-SNPA, Supplment 5: 311330.
Whittaker, J.E. 2003.A Micropalaeontological Analysis of the Lepe (Stone Point)
Pleistocene Deposits, Hampshire. The Natural History Museum, London.7pp.
6.The archaeological and sedimentary records from
Boxgrove and Slindon
Mark B. Roberts and Matthew I. Pope
Introduction: The Westbourne to Arundel Raised BeachBetween 2001 and 2006 the Boxgrove Project team undertook eldwork and
research to ascertain the total surviving extent of the sediments of the Slindon
Formation, which constitutes the bulk of the Boxgrove temperate depositional
sequence (Roberts et al. 1997; Roberts and Partt 1999): this work was entitled
the Raised Beach Mapping Project (Roberts 2003; Roberts and Pope in press).
The mapping project revealed that sediments of the Slindon Formation were
mappable over an east-west distance of 26 km, the resulting feature is now
known as the Westbourne to Arundel Raised Beach, reecting its two mapped
western and eastern extremities (Figure 6.1). The north to south survival
of the sediment stack, in front of the relict cliff line, was more variable. The
conformable sequence is best preserved in the eastern central area of the mappedextent (Figure 6.1), between the Valdoe and Slindon (Pope 2001; Pope et al. in
press); in this region the conformable sequence extends some 0.25 km south of
the cliff, with the unconformable sequence extending up to 0.80 km. Beyond
0.80 km the geliucted Palaeogene and Cretaceous regolith, together with the
gravel generated by cliff erosion and collapse, pinch out the marine Slindon Sand
Member and directly overlie the heavily weathered and dissected Chalk wave
cut platform. Elsewhere, preservation of the sediments is more variable, west
of the River Lavant between Trumley Copse and West Stoke the conformable
sequence is pinched out after less than 50 m in front of the cliff. West of Adsdean
Farm and east of Penfolds Pit at Slindon, the conformable sequence is lost as
the two ends of the beach begin to swing south and the cliff line diminishes
with the transition from Cretaceous to Palaeogene bedrock. Even in the central
areas, the conformable sequence is often disrupted by erosion associated with
slope processes and mass movement, such as at Goodwood, between Boxgrove
and the Valdoe, and Downs Farm, between Trumley and Adsdean (Figure 6.1).
The marine sediments of the Slindon Formation are also cut through by uvial
deposits of the Downland winterbournes, the Rivers Lavant and Ems (Figure
6.1), although the temporal relationship between these two sediment packages
has yet to be elucidated. The marine sediments are for the most part buried under
varying thicknesses of Head Gravel, that range from in excess of 15m in the
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centre of the distribution to a few meters where the beach crosses the Reading
Beds Formation. At either end of its distribution the beach achieves surfaceexpression and outcrops. In the east the beach can be found on or just below the
surface for 2 km between Tortington and Racton, whilst in the west it outcrops
over its nal 1 km in the area around Westbourne Common (Figure 6.1).
A physical relationship between the early Middle Pleistocene sediments of the
Slindon Formation and deposits of the next surviving marine trangression in the
coastal plain sequence, the Aldingbourne Raised Beach (Figure 6.2), has not been
demonstrated: although the BGS map an outcrop to the south east of Slindon,
at Binsted, where the two are in contact (Figure 6.1, 6.9). The Aldingbourne
Beach cuts through the weathered platform of the Westboune-Arundel Raised
beach and shares the same east-west distribution; this constrained extent is quite
different from the younger Brighton-Norton Beach, which extends some 30kmeast of the River Arun and runs continuously westward, passing immediately
to the south of Portsdown Hill. An age estimation from OSL has been obtained
from the Aldingbourne Sand, which correlates with a position in MIS 7. If this
date is correct it means that the palaeogeography of the coastal plain had to
change radically, early in the stage (see below), with the Brighton Norton event
either representing a later intra stage transgression or a regressing but expanded
coastline. An alternative proposition is that the Aldingourne sediments are older
and were laid down during MIS 11 or MIS 9.
Figure 6.2. The Arundel-Westbourne cliff line running westwards fromBoxgrove, through Goodwood into west Stoke and on to
Westbourne. Q1 = Quarry 1.
The disposition of the sediments of the Slindon Formation is thought to be
constrained by the Middle Pleistocene palaeotopography, which in itself was
determined by the solid geology and its associated structures (Roberts and
Pope in press), and has been described as the extant anticline hypothesis. The
hypothesis develops that proposed by Martin (1938), to explain why there were
no higher raised beaches to the east of the River Arun. Essentially, it is proposed
that the Littlehampton and Portsdown Anticlines exhibited signicant relief and
covered an area more closely related to their current mapped distribution (Figure
6.3), thus creating another range of Downs to the south of the current South
Downs dipslope. The extant anticline hypothesis demonstrates that there was
therefore no connection, except a temporal one, between the c. 40 m beaches
of the western Portsdown Anticline and the Slindon Formation, similarly the
proposed role of the River Solent in terms of contribution to the sedimentary
and biological regimes of the Boxgrove embayment can now be correspondingly
reduced. Marine transgression through the distal ends of the anticlines resulted
in the formation of a semi-enclosed marine bay (Barnes 1980), which became
progressively enlarged through time. At either end of the bay, where the energy
Figure 6.1. Location map showing the distribution of the Slindon
Formation.
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regime decreases, the littoral sediments arc southwards giving the entire sediment
package a gently parabolic shape. The wave cut platform within the bay includesPalaeogene sediments of the Reading and London Clay Formations to the south
and at the eastern and western extremity of the beach. In the centre of the bay
the platform extends across progressively older beds of the chalk in a classic
ofapping sequence. The time scale of eustatic sea level rise during an interglacial
is difcult to ascertain. However, the fact that fully interglacial faunas were able
to colonise the British Isles in successive temperate episodes, after the Anglian
breaching of the Weald-Artois Anticlinorum, suggests that there was a signicant
lag response between climatic amelioration and sea level heights, probably on
a 104 year scale. Erosion rates of the Palaeogene sediments were substantially
smaller than those of the Chalk but even with a time averaged retreat of 0.5m pa
in the relatively sheltered environment of the bay, the time required to achieve
the maximum point of transgression would only have been in the order of 6kyr. At the close of the interglacial, a similar but reverse lag response is visible,
whereby it appears that sea temperatures are cooling faster than the land. This
fact accounts for the more continental signature of the Boxgrove mammalian
faunas (Partt in Roberts et al. in prep) and also the presence of ice rafted exotic
rocks in all three members of the Slindon Formation (see below).
Explanations for the elevated height of Pleistocene raised beaches and
associated marine sediments above the present day sea level, have moved on
considerably since the formulation of simple eustatic and isostatic models, based
on Milankovitch cycle duration sea level rise and fall, and post continental
ice sheet depression and rebound, respectively. Current thinking links eustatic
and isostatic modeling with processes such as intraplate tectonics (Cloetingh
et al. 2005); crustal extension and shortening resulting in basin development
and basin inversion (Chadwick 1986; Lake and Karner 1986; Hopson 1999, in
press; Aldiss 2002); basement control of overlying Mesozoic structure though
reactivation of Variscan and older faults (Jones 1980, 1981, 1999a, 1999b; van
Vliet-Lano et al. 2000; Lagarde et al. 2003); post Cretaceous to Neogene upliftas a consequence of these aforementioned processes (Plint 1982; Mortimore and
Pomerol 1997; Gale et al. 1999; Evans and Hopson 2000; Blundell 2002); and
lithosphere controlled uplift related to sub crustal rheology, as a result of the
erosion and movement of proglacial continental sediment bodies coupled with
the effect of emplacement and displacement of glacial ice masses (Watts et al.
2005; Westaway et al. 2002, 2003; 2006). In an analysis of the structure and
uplift history of the Raised Beach Mapping Project survey area; all these process
will have played a role. The underlying geological structure of the survey area
and its associated tectonic activity is still active today and is responsible for
the preservation of the Westbourne Arundel Raised Beach, which since its
deposition has been uplifted somewhere in the region of 40m. (Maddy 1998;
Roberts and Partt 1999; Westaway et al. 2006). Although it is clear that uplift isa punctuated event, the 40m gure corresponds to c.8m per 100 kyr on average.
The combination of uplift and the eustatic rise in sea level in the ensuing
interglacial dictate whether raised beach sequences remain intact or are eroded
away and incorporated into the new beach. Similarly, intra interglacial sea level
uctuations can operate with the same effect.
The sediments of the Slindon Formation have been dated to the nal temperate
stage of the Cromerian Complex that in the United Kingdom is correlated with
MIS 13 (Roberts and Partt 1999; Preece and Partt 2000; Partt et al. 2007).
The overlying sediments of the Eartham Formation probably all belong to the
ensuing MIS 12 cold stage, the Anglian Glaciation. Other researchers such
as Bowen (Bowen and Sykes 1994); and Gard (1999) and Young (in Robertsand Pope in press) prefer a designation to MIS 11, based upon amino acid
racemisation and coccolith biostratigraphy, respectively. The MIS 11 age is
rejected because of the taxonomic composition of the Boxgrove mammal fauna
which contains species of both large and small mammals with regionally mapped
last occurrence data (LOD) in MIS 12 (Roberts and Partt 1999). Similarly, the
MIS 11 or Hoxnian Interglacial contains species with rst occurrence data that
almost certainly evolved from their Cromerian predecessors, in refugia, during
the Anglian. Boxgrove now heads a growing group of sites with a Cromerian
Figure 6.3. The coastline in the Boxgrove area at the end of MIS 13.
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surrounding intact Slindon Silts, together with a small but signicant amount of
highly calcareous material carried by the spring water discharge. The calcareous
component becomes greater up the prole (Figures 6.5, 6.6), as the availability
of other sediment sources declines. The pond deposits are in part capped by Unit
5a the ferric manganese organic bed of the standard sequence and by colluvial
deposits derived from erosion of the chalk gravel scree slopes in front of the cliff
(Table 6.1) (Figure 6.5); these latter deposits are associated with climatic decline
at the end of the Cromerian Complex and the advent of the ensuing Anglian
Glaciation in Marine Isotope Stage 12 at c. 480 kyr bp.
The inuence of freshwater into the catchment around Q1/B only becomes
apparent after marine regression, although rare freshwater and some euryhalineostracods in the standard sequence might reect the overall contribution of
spring fed freshwater into the neritic environment and localised reduction in net
salinities. Evidence for the initial deposition of freshwater sediments is found
in the main northwest-south east trending channel that runs through the site
(Figure 6.5) and in the truncated surface of Unit 3, the Slindon Sand, this unit
also exhibits smaller scour channels that migrate southwards across the surface.
The main channel, which achieves a maximum depth of 0.8m, is inlled with a
Figure 6.4. (a) The classic Boxgrove marine-terrestrial sequence from the
western edge of area Q1/B (left) and (b) the freshwater terrestrial
sequence from the middle of the Q1/B waterhole (right).
Figure 6.5. The channel deposits, Unit 3c, underlying the calcareous silts of
Unit 4. Note the preservation of Unit 5a, the organic bed, at this
part of the waterhole.
Figure 6.6. The excavated landsurface at the top of the marine Slindon Sand,
Unit 3, at Q1/B. The surface of the sand has been reworked by
freshwater emanating from springs issuing from the base of the
cliff, some 50m to the north of the site.
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coarse gravel deposit at the base, containing int beach pebbles, worked int and
bone fragments; the ne component of Unit 3c is largely arenaceous, with some
chalky clay deposition with ne to massive bedding (Macphail in Roberts et al.
in prep). Reworked and in situ lithics and faunal remains were found throughoutthe unit as well as chalk mud clasts and humic soil traces, indicating the erosion
of nearby landsurfaces. Outside of the main channel, the truncated surface of
Unit 3 has undergone pedogenesis and ripening prior to the deposition of Units
4u and 4 (Figures 6.6, 6.7), which constitute the main body of the freshwater
sediments. These processes along with an input of dung from mammals using
the waterhole, give rise to a phosphate-P concentration twice as great as that
encountered in the standard sequence at this stratigraphic level (Crowther in
Roberts et al. in prep). Similarly, the upper part of the sands at Q1/B contains
a signicantly higher silt component than elsewhere at the site, attesting to the
admixture of ner sediments from the Slindon Silt Member (Units 4a and 4b)
both during the truncation and subaerial weathering phase, and during the later
redeposition of the silts by the calcareous freshwater source.
The channel deposits are completely overlain by Unit 4u, the basal freshwater
unit of the waterhole sequence, and its associated sub-units 4us and 4.* (Table
6.1). Elsewhere in the waterhole Unit 4u only partially covers the Unit 3 surface,
whether this distribution mirrors its original deposition or if it has been partially
eroded, has yet to be elucidated. This unit is a massive silt with rare traces of
bedding, although in places a sandier facies, indicating higher energy deposition
has been noted. Unit 4u is overlain by Unit 4, the thickest and most extensive
Member
D
escriptionandInterpretation
Standard
Q1/B
Descriptionand
Interpretation
C
alcareousHead.Massmovement
deposit.
Unit10
Unit10
CalcareousHead.Massmovementdeposit.
EarthamUpperGravel
Pathgravel.Freezethawsortedint
gravel.
U
nit9
NotseenatQ1/B.
C
halk
pellet
gravel.
Waterlain,
w
eatheredandsortedchalkclasts.
U
nit8
Unit8
UpperChalkpelletgravel.Dewateringstructures
initiated.
EarthamLowerGravelC
liffcollapse.
U
nit7
NotseenatQ1/B,probably
toofarsouthofthecliff.
C
alcareous
muds/brickearth.
C
olluvialandwaterlainsilts.
Units5b,6
Unit6b
Calcareousmuds/brickearth
..Colluvialandwaterlain
silts.
M
ineralisedandcompressedorganic
deposits.Alder/fencarr.
Unit7
Unit5a
Unit5a
Mineralisedandcompresse
dorganicdeposits.Alder/
fencarr.
Soilhorizondevelopedontopofthe
silts.Poldertypesoil.
Unit4c
4d2,4d3,
5ac
Spring
dischargesedimen
tswith
colluvial,chalk
pellet,inputtowardsthetop
(5ac)
Unit4d1
Springdischargesediment.
Intraformationalcalcretes.
Unit4b
SlindonSilt
Intertidallaminatedmudslaiddown
in
a
Unit4
Massivesiltfrom
freshwaterreworkingofUnits4a
and4b.Heavilydeformed.
semi-enclosedmarinebay.
Unit4a
Unit4u
Massivenesiltfrom
freshwaterreworkingofUnits
4aand4b.Includessubunits
4usand4*
Units3/4,
3c
Freshwaterchannelsandfreshwaterscoured
landsurface,fromspringsatcliffbase.
Unit7
SlindonSand
N
ear-shoremarinesands.
U
nit3
Unit3
Nearshoremarine
sands
with
atruncated
upper
surface.
Table6.1.Stratigraphicrelationshipbetweenthestandard
Boxgrovesequenceandthatrecor
dedatQuarry1/B,the
springfedw
aterhole.Unit4canditschronostratigraphiccorrelativesareoutline
dinblack.Unit7isa
sedimentary
unitthatisincontinuousformatio
nuntiltheburialofthecliffbyma
ssmovementdeposits.
(Nottoscale).
Figure 6.7. Photomicrographs of M29, Q1B, Unit 3/4, showing detail
of curved pans of chalky mud at the base of a 80+ mm wide
depression (animal print?) that contains coarsely fragmented
sandy sediments; pans are also associated with the anomalous
concentrations of iron staining here that may be relict of inputs
of amorphous organic matter/dung. OIL and PPL frame widths
are ~4.62 mm.
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of the waterhole deposits, it comprises a dense massive silt that is relatively
homgenous at both the macro and micro scale, the unit has been heavily disturbed
by pore water release deformation structures from dewatering (Figures 6.5, 6.7),
most especially towards its surface. Macphail (ibid) has identied three phases
of deposition; the rst of which involves erosion and redeposition of Unit 4u
material; the second is characterised by an increase in plant detrital material and
bioturbation; and the third is characterised by massive calcareous silting under
an increasingly wet depositional regime.
The upper pond deposits begin with Unit 4d1, a highly calcareous white silt of
variable thickness that contains intraformational calcrete nodules, the source of
the carbonate is likely to be from directly from the Cretaceous Chalk at the cliff
base. Unit 4d1 is overlain by the highly mixed sediments of Unit 5ac (Figures 6.5
& 6.7), this poorly sorted deposit is predominantly a coarse silt, with subrounded
chalk clasts and sand size quartz grains. Bedding is occasionally present along
with organic laminae similar to but thinner than Unit 5a. The origins are Unit
5ac are a mix of redeposited pond sediments combined with upslope colluvial
deposits. Unit 5ac is succeeded by a return to highly calcareous spring deposition
of Units 4d2 and 4d3, which are in turn overlain by the marker horizon and
upper bed of the Slindon Silt Member, Unit 5a. This bed, between 10 and 15mm
thick has recently been mapped over a distance of 15km by Roberts and Pope(in press). Unit 5a comprises many microlaminations of detrital organic material
and was deposit in an alder/fen carr environment that developed on top of the
Slindon Silts. The colluvial sedimentation that overlies Unit 5a sees a reversion
to the standard stratigraphic sequence seen elsewhere at Boxgrove, although at
this part of the sequence certain units are not represented.
The waterhole or pond sediments described here were deposited under fully
interglacial conditions, as demonstrated by the taxonomic composition of
the mammalian, herpeto and ostracod faunas. Evidence for drying out of the
waterhole either in its entirety or through a shrinking shoreline, is attested to
by the presence of earthworm granules and discrete horizons containing dead
freshwater ostracod tests. The locale, which would have been rich in terrestrialand aquatic vegetation was utilised by many elements of the Boxgrove fauna,
including hominins (Figure 6.8). The remains of butchered rhinoceroses, deer
and other animals point to it being a place of food procurement and processing
as well as a water source (Figure 6.6). The whole of the depositional sequence
at Q1/B from the basal channel deposits up to the surface of Unit 4d3 was time
equivalent and thus a chronostratigraphic correlative of Unit 4c, the soil bed that
developed on the surface of the Slindon Silts after marine regression (Roberts
and Partt 1999).
Slindon
The village of Slindon is located on the dip slope of the South Downs; some 4km east of Boxgrove, 9 km east of Chichester and 12 km north of the current
English Channel at Middleton (Figures 6.1, 6.8). Various Middle Pleistocene/
Palaeolithic sites have been revealed along the line of the relict cliff of the
Westbourne-Arundel Raised Beach, both by the research of the Raised Beach
Mapping Project team and by earlier workers (Prestwich 1859; Calkin 1934;
Jeffries 1959; Woodcock 1981; Roberts and Pope in press). The sites running
from west to east are: Everymans Pit; Slindon Bottom; Slindon Park; Gaston
Farm and Penfoldss Pit. The sedimentary sequence at Slindon Park and Gaston
Farm were revealed in cable percussion boreholes whilst at the other locations,
sections were available after cleaning.
The bedrock of the cliff and wave cut platform largely comprises the Tarrant andNewhaven Members of the Upper Chalk Formation. However, in places, part of
the cliff and the solid to the north of the cliffs is made up of an elongate outlier
of Reading Beds. The Palaeogene deposits are preserved in a c. 4 km long, strike
parallel, normal fault. The downthrow, to the north of the fault, is estimated to be
in the region of 10 m (Hopsonpers comm.), with the surface footprint extending
to a maximum extent of 150 m. The presence of the impermeable Reading Beds
in the cliff has had important implications for Pleistocene coastal morphology,
preservation of organic sediments and Anglian snow-melt drainage.
Figure 6.8. Pre-mortem cut-marked incisors from the waterhole sediments
at Q1/B.
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Everymans Pit
This quarry contained the full sequence of Slindon and Eartham Formationdeposits and was very similar to that at Boxgrove, albeit further south of the cliff
and lacking the freshwater sediments (Woodcock 1981; Wessex Archaeology
1996; Wymer 1999). A handaxe was found on the oor of the pit by the Reverend
Fowler (1929) but there is little other lithic material recorded. In 2003 the authors
carried out a watching brief on a water transfer pipeline beginning at the Slindon
reservoir immediately to the north of Everymans Pit, and located the clifine
and raised beach, together with lithics and vertebrate microfauna (Roberts and
Pope 2004; Roberts et al. in prep).
Slindon Bottom
This site is probably the best known of all the Slindon exposures and until the
excavation of Boxgrove, produced the largest assemblage of Lower Palaeolithic
artefacts in Sussex. The site has been subject to sporadic collection by the likes
Jeffrey, and Zeuner who used to bring classes from the Institute of Archaeology
to the site; and focussed excavation by Calkin (1934), Woodcock (1981) and
Pope (2001). Excavation of the oor of Slindon Bottom by Pope (ibid), as part
of the RBMP rediscovered the original sections of Calkin and Woodcock along
with a handaxe and associated knapping debris. Previously, it had been proposedby Woodcock (1981) that Slindon Bottom represented a tidal inlet of the Slindon
Formation sea, that extended, through its connection with a downland valley
system, northwards beyond the relict cliff. However, test pitting across the valley
and to the north of the Slindon Eartham Road shows unequivocally that the cliff
and beach are extant in this area but have been reduced or removed by Pleistocene
snow melt discharge, leading to their preservation and exposure on either side of
the valley (Figure 6.14). It was the conguration and combination of the eastern
Eartham Valley and the Courthill Valley that therefore led to the formation of
Slindon Bottom, similar drainage patterns are also likely to be the precursors of
other substantial valley systems such as the Binsted Valley/Avisford Dell (Figure
6.9).
Slindon Park
Eleven boreholes were sunk in Slindon Park, immediately to the east of Slindon
Bottom (Figures 6.9-6.11). The boreholes proved a long 0.70 km north to south
sequence similar to that revealed by quarrying at Boxgrove and a west to east
sequence that revealed previously unrecorded organic deposits trending back into
the full conformable marine terrestrial sedimentary prole. The organic deposits
contain a late temperate pollen ora (Gibbard in Roberts and Pope in press)
(Figure 6.15), that includes Larch (larix) which appears to be an indicator species
for late Cromerian IV/ MIS 13 sites (Gibbard et al. 2003). Further examination
of selected levels of the organic deposits using micromorphology has revealed
well preserved plant detritus and wood charcoal (Macphail in Roberts and Pope
in press) (Figure 6.17) The stratigraphic correlation of these organic sediments
with the sequence recorded at sites such as the Valdoe, Boxgrove, Everymans
Pit and Slindon Park east requires further borehole work. However, they are
possibly a local continuation of the freshwater organic beds of Unit 5a that have
been mapped over a distance of 15 km between Adsdean and Slindon (Figure
6.1). The organic beds do however thicken to the west and achieve their greatest
extent in BHs 2 and 3, where they unconformably overlie the marine Slindon
Sand, it may be that they were deposited in a actively owing freshwater system
that was a prototype of the Slindon Bottom valley.
Figure 6.9. Geology of the area around Slindon showing the line of the
Slindon-Park Farm normal fault. Note the oulier of Reading
Beds preserved by the fault, to the south of Slindon Village.
SCk=Seaford Chalk; NCk=Newhaven Chalk; TCk=Tarrant
Chalk; SPCk=Spetisbury Chalk; ReaB=Reading Beds;
LClay=London Clay; URBs=Upper Raised Beaches; Lower
Raised Beaches; Cwf=Clay-with-ints; HGrvl=Head Gravel;
Be=Brickearth; TAlluv=Tidal Alluvium.
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The QuaTernary of Th e SolenT BaS in an d WeS T SuSSex raiSedBeacheS
Figure 6.10. Slindon Park looking south from the downland dipslope to-
wards the coastal plain. Note the break of slope that indicates
the position of the buried cliff line.
Figure 6.11. Plan showing the location of boreholes in Slindon Park.
Figure 6.12. West to east borehole logs through the stratigraphy at
Slindon.
Figure 6.13. North to south borehole logs through the stratigraphy at
Slindon.
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The QuaTernary of Th e SolenT BaS in an d WeS T SuSSex raiSedBeacheS
Figure 6.14. Geliucted Reading Beds and Chalk overlying the surface of
the beach at Slindon Bottom.
Figure 6.15. Pollen diagram from the organic deposits in Borehole 5 at
Slindon Park.
Figure 6.16 a-f. Examples of sediment micromorphology from Slindon Park
BH5.
Figure 6.16a. U100 from BH5.
Figure 6.16b. Scan of 50 mm long thin section
BH5-M.2B; contains many plant
fragments some large and well
preserved.
Figure 6.16e. Scan of 60 mm long thin section
BH5-M.3A; contains layer of
wood charcoal.
Figure 6.16c. Detail of Fig. 16b, long plant
fragment; Plane polarised light
(PPL), frame width is ~7.7 mm
Figure 6.16d Detail of Fig. 16c , well preserved
blue light autofuorescent plant
tissues. Frame width is ~1.6 mm.
Figure 6.16f Detail of wood charcoal in non-
calcareous iron-stained clay. PPL,
frame width is ~7.7 mm.
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Gaston Farm
Three boreholes were sunk at Gaston Farm (Figure 6.17); the rst was abandoned
after less than 2m as it went directly into the Reading Beds, eighty metres to
the south BH2 was drilled down through almost 25m of relatively homogenous
silts before the hole was abandoned. However, a further seventy metres south of
BH2, BH3 passed back into the normal sequence. Whether the unique sequence
at BH2 is the result of snow melt run-off over the impermeable Reading beds
cliff creating a plunge pool or a feature of the fault line itself is as yet unknown.
Samples looking for mammals, freshwater invertebrates and pollen all proved
barren.
Penfolds Pit
The most easterly of the Slindon sites Penfolds Pit is at the northern end of
the Binsted Valley, which is the modern name of Prestwichs Avisford Dell
(1898). Penfolds Pit like Everymans Pit to the west, is located on the side of the
valley, and has produced numerous handaxes from residual contexts (Pyddoke1950; Woodcock 1981). Detailed records were made by Jeffrey (1957, 1960)
who recorded two levels of beach, a phenomenon noted in GTP 13 at Boxgrove
(Collcutt in Roberts and Partt 1999) and the fact that the pebbles from the basal
beach were sat in a pink clay like eggs in a box. It is now clear that the clay was
derived from the Reading beds that form part of the cliff at this site. Penfolds
Pit is now completely overgrown but would repay diligent section cleaning if the
opportunity arose.
Acknowledgements
The authors are grateful to English Heritage for their funding of the Raised Beach
Mapping Project and the Boxgrove Project. We extend our thanks to the many
landowners who facilitated our research by allowing access and investigation.We are indebted to Richard Macphail and Phillip Gibbard for their work on
the micromorphology and palynology, and most importantly to John Whittaker
for his work on the invertebrate microfauna, and his unstinting support of our
research.
References
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Barnes 1980
Blundell 2002
Bowen 1999
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Calkin 1934
Cloetingh et al. 2005
Chadwick 1986;
Evans and Hopson 2000;
Gard (1999)
Gibbard et al. 2003
Hedberg 1986,
Figure 6.17. Boreholes at Gaston Farm revealing the great depth of inll
deposits in front of the cliff at BH2. Both axes scaled in metres,
Y axis is m OD.
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