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Th
e R
ive
r E
xe
: A
Fie
ld G
uid
e t
o t
he
Pala
eo
lith
ic L
an
dscap
e
P
ictu
re o
f E
xe f
loodpla
in fro
m F
ort
escue F
arm
taken b
y L
aura
Basell
(PR
oS
WeB
)
Pro
du
ce
d b
y
Th
e P
ala
eo
lith
ic R
ive
rs o
f S
ou
th-W
es
t B
rita
in P
roje
ct
a
nd
th
e
Na
tio
na
l Ic
e A
ge
Ne
two
rk
Funde
d b
y th
e A
ggre
gate
s L
evy S
usta
inabili
ty F
und
th
rough E
nglis
h H
eri
tag
e
Ple
as
e n
ote
th
at
the
fli
nt
kn
ap
pin
g d
em
on
str
ati
on
wil
l ta
ke
pla
ce
sh
ort
ly a
fte
r th
e w
alk
fin
ish
es
. T
he
re a
re a
dd
itio
na
l d
isp
lays
ab
ou
t P
ala
eo
lith
ic a
rch
ae
olo
gy
in
th
e v
illa
ge
ha
ll
an
d o
rig
ina
l a
nd
re
plic
a P
ala
eo
lith
ic s
ton
e t
oo
ls w
ill
be
on
d
isp
lay.
Re
fere
nc
e
Whitto
w,
J.
20
00
. T
he
Pe
ngu
in D
iction
ary
of P
hysic
al G
eo
gra
ph
y
(2nd E
ditio
n).
Pen
gu
in B
oo
ks: L
on
don
. N
ote
T
he
info
rmatio
n in
th
is g
uid
e is d
erive
d f
rom
a n
um
be
r of
diffe
ren
t so
urc
es in
clu
din
g B
GS
map
she
ets
, a
ccom
pan
yin
g m
em
oirs a
nd
Je
nn
y B
enn
ett’s
unp
ublis
he
d P
hD
the
sis
(U
niv
ers
ity o
f E
xe
ter)
. P
Ro
SW
eB
an
d N
IAN
wo
uld
lik
e t
o t
ha
nk J
enn
y B
en
nett
an
d th
e
BG
S fo
r th
eir a
ssis
tan
ce
on t
his
pro
ject.
4.
He
re t
he r
ive
r is
cu
ttin
g t
hro
ugh
a n
eck in t
he n
ort
he
rn b
an
k to
fo
rm a
gra
ve
l is
lan
d.
Bo
th s
ide
s o
f th
e v
alle
y c
an
be
see
n f
rom
h
ere
, w
ith
Te
rra
ce
4 d
ep
osits o
n e
ith
er
sid
e g
ivin
g a
n
imp
ressio
n o
f h
ow
la
rge
the
riv
er
syste
m m
ust
ha
ve
be
en.
Lo
okin
g s
ou
th to
wa
rds E
xe
ter,
the
ra
ise
d g
rou
nd
to
th
e s
ou
th
we
st
is S
toke
Hill
. T
he
re a
re th
e r
em
ain
s o
f a
Ro
man
fo
rt
he
re, o
ve
rlo
okin
g t
he
riv
er
va
lley.
5.
Ma
ny s
ou
rce
s o
f in
form
ation
can
be
use
d to
dis
ce
rn f
orm
er
rive
r ch
an
ne
ls.
Bra
mpfo
rd S
pe
ke
ha
s a
n A
nglo
-Sa
xo
n c
ha
rte
r so
the
pa
rish
bou
nd
ary
is lik
ely
to
be
at
lea
st a
tho
usan
d y
ea
rs
old
. T
he
lin
e o
f th
e p
arish
bou
nda
ry is s
inu
ou
s,
su
gge
stin
g t
he
lin
e o
f a
riv
er
ch
an
ne
l, a
nd
se
ve
ral of
the
ab
an
don
ed
ch
an
ne
ls
vis
ible
fro
m h
ere
fo
llow
th
e lin
e o
f th
e p
arish
bo
und
ary
. It
se
em
s lik
ely
th
at
the
se p
ala
eo
cha
nne
ls w
ere
pa
rt o
f th
e m
ain
ch
ann
el in
th
e 1
1th
centu
ry.
6.
He
re a
rou
nd
ba
rro
w (
Bro
nze
Age
) ca
n b
e s
ee
n f
rom
th
e p
ath
, a
nd
th
ere
is a
no
the
r to
th
e n
ort
h. T
he
se
ba
rrow
s a
re b
oth
on
th
e s
urf
ace
of
Te
rra
ce
2,
an
d g
ive
a b
road
age
co
nstr
ain
t fo
r th
e te
rra
ce
(i.e
. th
e t
err
ace
mu
st h
ave
be
en f
orm
ed
befo
re th
e
ba
rro
w w
as b
uilt
!).
Inte
restin
gly
th
ere
are
no
ho
use
s o
n th
e
floo
dp
lain
, a
pa
rt f
rom
th
e S
tation
Ho
use
, o
n th
e r
ais
ed
ra
ilwa
y
em
ba
nkm
en
t.
7.
The
gro
un
d h
ere
ris
es f
rom
Te
rra
ce
2 to
Te
rra
ce
3. T
he b
rea
k
of
slo
pe
be
twe
en
th
em
is q
uite
su
btle
, a
s is t
he
altitud
ina
l d
iffe
ren
ce
.
8.
As t
he e
dge
of
Te
rra
ce 2
is c
rossed
(a
nd
we
re
turn
ba
ck o
nto
th
e f
loo
dp
lain
), th
ere
is e
vid
en
ce
of
larg
e p
ala
eo
cha
nne
ls o
n
bo
th s
ide
s o
f th
e p
ath
, su
gge
stin
g t
ha
t an
ea
rlie
r co
urs
e o
f th
e
ma
in r
ive
r flo
we
d a
long t
he
ed
ge
of
the T
err
ace
.
9.
The
re is a
no
the
r go
od
vie
w o
f th
e r
ive
r clif
f at B
ram
pfo
rd
Sp
eke f
rom
he
re.
Yo
u c
an
als
o s
ee t
he
va
lley t
o th
e s
ou
th o
f B
ram
pfo
rd S
pe
ke
. T
his
va
lley p
ost-
da
tes T
err
ace
4.
Sim
ilar
va
lleys (
cu
ttin
g t
hro
ugh
Te
rra
ce
4)
are
co
mm
on
ly f
ou
nd in
th
e
sa
me s
tra
tigra
ph
ic p
ositio
n t
hro
ugh
out
the
Exe
va
lley.
Th
ey
are
usua
lly f
ille
d w
ith
he
ad
de
po
sits (
pu
rple
on
the
wa
lk m
ap
).
10
. A f
urt
he
r se
rie
s o
f d
istin
ctive
pa
laeo
ch
an
ne
ls c
an
be
see
n
he
re, a
fin
al re
min
de
r of
the
dyn
am
ic n
atu
re o
f th
e R
ive
r E
xe
a
t va
rio
us t
ime
s in
its
pa
st
an
d p
rese
nt.
A F
ield
Gu
ide
to
th
e P
ala
eo
lith
ic L
an
dsca
pe
: T
he
R
ive
r E
xe
W
ritte
n a
nd
pre
pa
red
by T
he
Pa
laeo
lith
ic R
ive
rs o
f S
ou
th-W
est
Brita
in P
roje
ct
Intr
od
uc
tio
n
The
Lo
we
r a
nd
Mid
dle
Pa
laeo
lith
ic is g
en
era
lly c
on
sid
ere
d to
ha
ve
la
ste
d f
rom
c.
70
0,0
00 y
ea
rs a
go
to
c. 4
0,0
00 y
ea
rs a
go
, e
nd
ing d
urin
g
the
De
ve
nsia
n g
lacia
tio
n.
At
va
rio
us t
ime
s d
urin
g t
his
pe
rio
d B
rita
in
wa
s s
till
linke
d t
o m
ain
lan
d E
uro
pe
, w
ith
a ‘la
nd
brid
ge
’ str
etc
hin
g f
rom
H
ull
rou
nd
to
Ea
stb
ou
rne
. D
urin
g t
he
Lo
we
r a
nd
Mid
dle
Pa
lae
olit
hic
B
rita
in w
as s
pa
rse
ly,
an
d p
rob
ab
ly o
nly
in
term
itte
ntly,
inh
ab
ite
d b
y
diffe
rent fo
rms o
f ho
min
ins (
a t
yp
e o
f p
re-m
od
ern
hum
an
): H
om
o
he
ide
lbe
rgen
sis
du
rin
g t
he
Lo
we
r P
ala
eo
lith
ic a
nd t
he
n H
om
o
Ne
an
de
rth
ale
nsis
du
rin
g t
he
Mid
dle
Pa
lae
olit
hic
. M
ost
Lo
we
r a
nd M
idd
le P
ala
eo
lith
ic a
rch
ae
olo
gy is f
ou
nd
in
riv
er
se
dim
en
ts a
nd
ca
ve
s. W
hils
t a
rtefa
cts
re
co
ve
red
fro
m c
ave
s h
ave
oft
en
(b
ut ce
rta
inly
no
t a
lwa
ys)
no
t m
ove
d fa
r fr
om
th
e p
lace t
he
y
we
re o
rig
ina
lly d
isca
rde
d, 8
0-9
0%
of
kn
ow
n L
ow
er
an
d M
idd
le
Pa
laeo
lith
ic a
rcha
eo
log
y (
ma
inly
sto
ne
to
ols
) h
as b
een
fo
und
w
ith
in r
ive
r sa
nd
s a
nd
gra
ve
ls.
The
sto
ne
to
ol a
rch
aeo
logy o
f th
e
rive
r se
dim
en
ts (
the
san
ds a
nd
gra
ve
ls),
wh
ile s
om
etim
es d
ifficu
lt
to in
terp
ret,
is th
ere
fore
im
po
rtan
t to
ou
r u
nde
rsta
nd
ing o
f th
e
Pa
laeo
lith
ic p
erio
d. L
ike
oth
er
are
as o
f B
rita
in t
he
so
uth
-we
st
regio
n h
as m
an
y e
xa
mp
les o
f th
is s
ort
of
arc
ha
eo
logy,
mo
st
no
tab
ly t
he
ric
h a
sse
mb
lage
of
Lo
we
r P
ala
eo
lith
ic a
rtefa
cts
fro
m
the
gra
ve
ls o
f th
e A
xe
Riv
er
at
Bro
om
, o
n t
he D
evo
n/D
ors
et
bo
rde
r.
On
e o
f th
e m
ajo
r a
ims o
f th
e P
ala
eo
lith
ic R
ivers
of
Sou
th-W
est
Brita
in (
PR
oS
WeB
) p
roje
ct
is to
re
co
rd a
nd
da
te th
e te
rra
ce
s o
f th
e r
ive
rs A
xe
, E
xe
and
Otte
r a
nd
eva
lua
te the
ir a
rch
aeo
logic
al
co
nte
nt a
nd p
ote
ntia
l. M
an
y s
an
d a
nd
gra
ve
l qu
arr
ies in
th
e U
K
op
era
te w
ith
in r
ive
r te
rra
ce
sed
ime
nts
ric
h in
Pa
laeo
lith
ic a
rtefa
cts
a
nd
th
e N
atio
na
l Ic
e A
ge
Ne
two
rk (
NIA
N)
is w
ork
ing w
ith
th
e
aggre
ga
tes in
du
str
y t
o e
sta
blis
h a
pro
toco
l fo
r re
po
rtin
g a
nd
id
en
tify
ing P
ala
eo
lith
ic f
ind
s u
nco
ve
red
du
rin
g q
ua
rryin
g.
Th
is w
alk
will
fo
llow
so
me
of
the
riv
er
terr
aces a
nd t
he
flo
od
pla
in
of
the
Riv
er
Exe
. W
e w
ill d
iscu
ss t
he
fo
rma
tion
of
rive
r te
rra
ce
s
(se
e t
he
Ke
y C
on
ce
pts
se
ctio
n),
pro
ce
sse
s o
f la
nd
sca
pe
ch
an
ge
, a
nd
so
me
of
the
te
ch
niq
ue
s t
hat
are
used
to s
tud
y r
ive
rs a
nd
th
eir
de
po
sits. W
e w
ill a
lso
dis
cu
ss t
he
arc
ha
eo
logy o
f th
e P
ala
eo
lith
ic
in t
he s
outh
-we
st
regio
n b
oth
du
rin
g a
nd
aft
er
the
wa
lk.
We h
ope
th
at b
y t
he
en
d o
f th
e w
alk
yo
u w
ill h
ave
a b
ette
r u
nde
rsta
nd
ing o
f th
e L
ow
er
an
d M
idd
le P
ala
eo
lith
ic p
eriod
in
th
e
so
uth
-we
st,
the
Riv
er
Exe
la
nd
scap
e, a
nd
som
e o
f th
e te
chn
iqu
es
an
d m
eth
od
s u
se
d in
th
e s
tud
y o
f P
ala
eo
lith
ic g
eo
arc
hae
olo
gy.
Ke
y t
erm
s
Th
is s
ectio
n in
clu
de
s s
om
e o
f th
e k
ey t
erm
s a
nd
con
ce
pts
use
d in
this
fie
ld g
uid
e (
aft
er
Wh
itto
w 2
00
0).
A
llu
viu
m:
Th
e s
ed
imen
ts d
ep
osite
d in r
ive
r ch
ann
els
an
d
floo
dp
lain
s b
y t
he
flo
win
g w
ate
r o
f str
eam
s a
nd
riv
ers
, in
clu
din
g
gra
ve
ls,
sa
nd
s, cla
ys a
nd
silt
s. T
he
gra
ve
ls a
nd
san
d o
f floo
dp
lain
s (
see
be
low
) a
nd t
err
ace
s (
se
e b
elo
w)
ha
ve
be
en
co
mm
erc
ially
qu
arr
ied
fo
r m
an
y y
ea
rs a
nd
th
is q
ua
rryin
g h
as
oft
en
le
d t
o th
e d
isco
ve
ry o
f P
ala
eo
lith
ic s
tone
too
ls w
ith
in t
he
se
dim
en
ts.
An
gli
an
: T
he m
ost e
xte
nsiv
e g
lacia
tio
n o
f th
e B
ritish
Mid
dle
P
leis
tocen
e (
the
pe
rio
d b
etw
ee
n c
. 78
0,0
00–
12
5,0
00
BP
), d
urin
g
wh
ich
gla
cie
r ic
e c
am
e a
s f
ar
so
uth
as th
e B
risto
l C
han
ne
l a
nd
wh
at
is n
ow
no
rth
Lo
nd
on
. C
oll
uviu
m:
Se
dim
ents
de
po
site
d a
t th
e b
ott
om
of
slo
pe
s,
aft
er
be
ing t
ran
sp
ort
ed
by g
ravita
tio
na
l fo
rce
s.
De
ve
ns
ian
: T
he
la
st gla
cia
l (s
ee
be
low
) o
f th
e B
ritish
P
leis
tocen
e,
lastin
g b
etw
ee
n c
. 70
,00
0–1
0,0
00
ye
ars
ago
.
2.
The
flo
od
pla
in c
on
sis
ts o
f gra
ve
l o
ve
rla
in b
y s
ilts,
and
if
the
w
ate
r le
ve
l in
th
e r
ive
r is
lo
w t
he
n th
e g
rave
ls c
an
be
see
n
from
th
e b
rid
ge
, o
r, in a
sh
ort
div
ers
ion
, in
the
sid
e o
f th
e fo
rd
on
th
e o
the
r sid
e o
f th
e g
ate
at th
is p
oin
t. T
he r
ive
r p
eb
ble
s
(kn
ow
n a
s c
lasts
) a
re s
ligh
tly r
ou
nd
ed
and
mostly f
lat
in
sh
ape
, an
d th
e r
ock t
yp
es m
ain
ly s
late
s a
nd s
an
dsto
ne
s,
with
o
cca
sio
na
l p
iece
s o
f qu
art
z.
Ro
cks o
f th
ese
typ
es a
nd
age
s
(th
e s
late
s a
nd
sa
nd
sto
ne
s a
re D
evo
nia
n (
410
–36
0 m
ya
) a
nd
C
arb
on
ife
rou
s (
360
–2
90
mya
)) a
re a
ll fo
und
be
twe
en
he
re
an
d E
xm
oo
r. T
he
slig
htly r
ais
ed
gro
un
d o
n t
he
we
ste
rn s
ide
of
the
riv
er,
ne
ar
this
ob
se
rva
tio
n p
oin
t is
Te
rra
ce
1.
3.
On
ce
ove
r th
e e
mba
nkm
ent
of
the
dis
ma
ntle
d r
ailw
ay lin
e (
the
o
ld E
xe
Va
lley L
ine
) th
e n
ext fie
ld s
ho
ws m
any r
idge
s a
nd
p
ala
eo
ch
an
ne
ls. T
he
se
are
Ho
loce
ne
fe
atu
res,
and
pro
ba
bly
re
pre
se
nt
ea
rlie
r po
sitio
ns o
f th
e r
ive
r ch
an
nel. L
oo
kin
g n
ort
h,
on
th
e w
este
rn s
ide
of th
e r
ive
r, T
err
ace
4 o
ve
rlie
s t
he
riv
er
clif
f a
t F
ort
escu
e. T
he c
liff
he
re c
on
sis
ts o
f bed
rock,
with
T
err
ace 2
map
ped
at
its f
oo
t. A
nim
al scra
pe
s in
th
e c
liff
sho
w
as o
ran
ge
-re
d m
ark
s, w
he
re t
he
be
dro
ck is r
eve
ale
d (
se
e
figu
re b
elo
w).
F
ort
escue r
iver
clif
f (r
epro
duced fro
m J
. B
ennett’s
unpublis
hed P
hD
thesis
, U
niv
ers
ity o
f E
xete
r w
ith p
erm
issio
n)
Po
ints
of
inte
res
t G
en
era
l
•
The
ma
jority
of
the
wa
lk is c
on
ce
rne
d w
ith
su
pe
rfic
ial
ge
olo
gy (
i.e
. a
lluviu
m a
nd
co
lluviu
m,
wh
ich
are
u
ncon
so
lida
ted
se
dim
en
ts)
as o
ppo
se
d t
o b
ed
roc
k g
eo
log
y
(i.e
. h
ard
ro
cks s
uch
as g
ran
ite
).
•
The
ora
nge
are
as a
re r
ive
r te
rra
ce
s (
bo
th th
e la
ndfo
rm a
nd
the
te
rra
ce
de
po
sits).
On
th
is m
ap
th
ey a
re o
fte
n d
ivid
ed
in
to
se
pa
rate
te
rra
ce
un
its. D
urin
g t
he
wa
lk lo
ok o
ut fo
r te
rra
ce
s
at
sim
ilar
he
igh
ts o
n e
ith
er
sid
e o
f th
e r
ive
r va
lley (
i.e
. o
n
bo
th s
ide
s o
f th
e r
ive
r) —
pa
ire
d te
rra
ce
s o
f sim
ilar
he
igh
ts
(an
d th
ere
fore
age
) can
giv
e u
s v
alu
ab
le info
rma
tion
ab
ou
t ri
ve
r va
lley e
vo
lutio
n a
nd
cha
nge
ove
r tim
e.
•
The
ye
llow
are
as a
re m
ode
rn (
Ho
loce
ne
) a
lluvia
l d
ep
osits.
Fo
rme
r rive
r ch
an
ne
ls (
pa
lae
och
an
ne
ls)
can
be
see
n in
the
se d
ep
osits, a
nd
org
an
ic r
em
ain
s f
ou
nd in t
he
p
ala
eo
ch
an
ne
l d
ep
osits c
an
be
rad
ioca
rbo
n d
ate
d t
o p
rovid
e
de
taile
d info
rmatio
n a
bo
ut
rive
r ch
an
ne
l m
ove
me
nts
acro
ss
the
cu
rre
nt flo
odp
lain
du
rin
g t
he
Ho
loce
ne.
•
The
pu
rple
are
as o
n the
ma
p r
ep
resen
t he
ad
de
po
sits (
se
e
Ke
y T
erm
s).
S
pe
cif
ic O
bse
rva
tio
n P
oin
ts (
se
e n
um
be
rs o
f th
e W
alk
Ma
p)
1.
The
vill
age
of
Bra
mpfo
rd S
pe
ke
is b
uilt
on r
ive
r te
rra
ce
gra
ve
ls.
Gra
ve
ls o
f th
e 4
th R
ive
r T
err
ace c
an b
e s
ee
n o
n th
e
no
rth
ern
(le
ft h
and
) sid
e o
f th
e p
ath
wa
y d
ow
n t
o th
e
floo
dp
lain
. M
an
y o
f th
e p
ebb
les a
re v
ert
ica
lly o
rie
nta
ted
he
re,
su
gge
stive
of
fro
st h
eave
in
pe
rigla
cia
l co
nd
itio
ns.
At
the
b
otto
m o
f th
e p
ath
, th
e b
ed
rock is e
xp
osed
. T
his
is o
f P
erm
ian
a
ge
, fr
om
the
Exe
ter
Gro
up
of
the
Ne
w R
ed
Sa
nd
sto
ne (
abo
ut
30
0 m
illio
n y
ea
rs o
ld).
The
gra
ve
ls h
ave
slu
mp
ed
an
d t
he
re is
a g
rea
t de
al of m
ode
rn v
ege
tatio
n m
akin
g t
he c
on
tact
be
twe
en
th
e g
rave
l a
nd
the
be
dro
ck d
ifficu
lt to
se
e. T
he
re is a
cle
ar
altitud
ina
l b
rea
k b
etw
ee
n T
err
ace
s 4
and
3,
with
T
err
ace
s 3
, 2
, a
nd 1
situ
ate
d a
dja
cen
t to
, an
d ju
st
a fe
w
me
tre
s a
bo
ve
, th
e m
ode
rn f
lood
pla
in.
Flo
od
pla
in: T
he
pa
rt o
f a
riv
er,
ne
xt
to th
e c
ha
nne
l, o
ve
r w
hic
h
the
riv
er
flo
ws d
urin
g p
erio
ds o
f flo
od
ing. T
he f
loo
dp
lain
con
sis
ts
of
allu
viu
m (
see
ab
ove
) a
nd
oft
en
in
clu
de
s p
ala
eo
cha
nne
ls (
se
e
be
low
).
Gla
cia
l: O
ften
mo
re c
om
mo
nly
re
ferr
ed
to
as a
n ‘ic
e a
ge
’, a
gla
cia
l is
a g
eo
logic
al p
erio
d o
f tim
e d
urin
g w
hic
h t
he
clim
ate
co
ole
d s
ign
ific
an
tly (
a g
lacia
l is
a c
old
ph
ase
) a
nd B
rita
in w
as a
t le
ast
pa
rtia
lly c
ove
red
in
gla
cie
r ic
e.
Gla
cia
l m
ax
imu
m: T
he
la
rge
st
exte
nts
ach
ieve
d b
y g
lacie
rs (
ice
sh
ee
ts)
du
rin
g a
gla
cia
l p
erio
d.
He
ad
: A
ma
ss o
f sa
nd
, gra
ve
l a
nd
cla
y p
rod
uce
d b
y s
olif
luction
(s
ee
be
low
) u
nd
er
pe
rigla
cia
l co
nd
itio
ns (
se
e b
elo
w)
du
rin
g t
he
P
leis
tocen
e (
see
be
low
). I
t is
oft
en
fo
un
d f
illin
g v
alle
y b
ott
om
s.
Ho
loc
en
e: T
he
cu
rre
nt ge
olo
gic
al p
erio
d,
wh
ich
sta
rted
ab
ou
t 1
0,0
00
ye
ars
ago
, a
nd
wh
ich
is c
ha
racte
rise
d b
y g
en
era
lly w
arm
(t
em
pe
rate
) co
nd
itio
ns.
Inte
rgla
cia
l: A
ge
olo
gic
al p
erio
d o
f tim
e b
etw
ee
n tw
o g
lacia
l p
erio
ds w
he
n th
e c
limate
wa
rme
d s
ign
ific
antly (
an
in
terg
lacia
l is
a
tem
pe
rate
ph
ase
), a
nd t
em
pe
ratu
res w
ere
sim
ilar
to th
ose
of
the
p
rese
nt d
ay.
Ma
/mya
: m
illio
n y
ea
rs/m
illio
n y
ea
rs a
go
N
ec
k: A
ne
ck is a
na
rro
w s
trip
of
lan
d s
imila
r to
an
isth
mu
s
Pa
lae
oc
ha
nn
els
: A
ban
don
ed
riv
er
or
str
eam
ch
ann
els
th
at n
o
lon
ge
r ca
rry w
ate
r a
nd
wh
ich
in
dic
ate
old
er
rou
tes o
f th
e r
ive
r.
Pe
rig
lac
ial:
The
are
a a
rou
nd
the
frin
ge
s o
f a g
lacie
r o
r ic
e-s
he
et.
The
gro
un
d s
urf
ace
is s
ub
jecte
d to
re
pe
ate
d fre
ezin
g a
nd
th
aw
ing,
an
d to
dis
tin
ctive
pro
ce
sse
s s
uch
as s
olif
luctio
n (
see
b
elo
w),
wh
ile t
he
un
derl
yin
g g
rou
nd
is p
erm
an
en
tly f
roze
n.
Ple
isto
ce
ne
: A
ge
olo
gic
al p
erio
d w
hic
h s
tart
ed
abo
ut 1
.6 m
illio
n
ye
ars
ago
an
d e
nd
ed
aft
er
the
De
ve
nsia
n (
see
abo
ve
) a
t 10
,00
0
ye
ars
ago
(th
e s
tart
of
the
Ho
loce
ne
). I
t co
nsis
ts o
f a
se
rie
s o
f gla
cia
ls a
nd
in
terg
lacia
ls (
se
e a
bo
ve
).
So
lifl
uc
tio
n:
Lite
rally
“so
il flo
w”
or
the
slo
w m
ove
me
nt of
so
ils
do
wn
slo
pe
. P
erigla
cia
l p
roce
sse
s (
free
ze
and
th
aw
) m
ake
th
e s
oil
pa
rtic
les u
nsta
ble
an
d p
rod
uce
en
ou
gh
wa
ter
to a
id t
he
ir
mo
ve
me
nt d
ow
nslo
pe
. T
err
ace
: S
ee
Ke
y C
once
pts
. K
ey c
on
ce
pts
R
ive
r te
rra
ce d
eve
lop
me
nt:
riv
er
terr
ace
s a
re r
em
nan
ts o
f th
e
form
er
flo
odp
lain
(see
ab
ove
) of
a r
ive
r th
at
ha
ve
be
en
ab
an
don
ed a
nd
left
at a
hig
he
r le
ve
l a
s th
e r
ive
r d
ow
ncu
ts.
Th
e
term
te
rra
ce
refe
rs t
o b
oth
th
e la
ndfo
rm (
wh
ich
ha
s t
he
a
ppe
ara
nce
of
a b
en
ch in
pro
file
) an
d to
th
e a
lluvia
l d
ep
osits o
f th
e fo
rme
r flo
od
pla
in (
e.g
. sa
nd
s a
nd
gra
ve
ls)
wh
ich
are
la
id
do
wn
on
th
e f
loo
dp
lain
du
rin
g p
erio
ds o
f flo
odin
g.
Riv
er
do
wn
cu
ttin
g (
lea
din
g t
o th
e f
orm
ation
of
terr
ace
s)
app
ea
rs
to o
ccu
r a
s a
re
su
lt o
f th
e g
lacia
l/in
terg
lacia
l clim
atic c
ycle
s o
f th
e
Ple
isto
cen
e. In
sim
ple
te
rms:
1.
Se
a le
ve
l fa
ll (w
hic
h o
ccu
rs d
urin
g g
lacia
l p
erio
ds a
s la
rge
qu
an
titie
s o
f glo
ba
l se
aw
ate
r a
re lo
cke
d u
p in
ice
sh
ee
ts o
n
the
lan
d)
resu
lts in
riv
ers
re
-ad
justin
g t
he
ir p
rofile
, a
s t
he
ir
ultim
ate
de
stina
tio
n p
oin
t (t
he s
ea
) is
no
w lo
we
r a
nd f
urt
he
r a
wa
y.
Th
is is a
ch
ieve
d b
y d
ow
ncu
ttin
g a
nd c
rea
tin
g b
oth
a
ne
w,
low
er
flo
odp
lain
an
d a
ne
w t
err
ace
(ab
an
don
ed
at a
h
igh
er
leve
l).
2.
Se
a le
ve
l rise
(w
hic
h o
ccu
rs a
t th
e s
tart
of
an
in
terg
lacia
l a
s
the
ice s
hee
ts m
elt a
nd
the
wa
ter
retu
rns to
th
e s
ea
s)
resu
lts
in s
ed
ime
nta
tion
of
the lo
we
st
rea
ch
es (
i.e.
ne
ar
the
coa
st)
of
the
riv
ers
’ n
ew
flo
od
pla
in.
3.
Up
lift of
the
la
nd (
in r
esp
on
se
to t
he
re
mo
va
l of
sed
imen
t th
rou
gh
ero
sio
n a
nd t
he
re
mo
va
l of
the
we
igh
t of
ice
) o
ccu
rs
gra
du
ally
th
rou
gh
ou
t ea
ch
gla
cia
l/in
terg
lacia
l cycle
an
d t
he
risin
g o
f th
e lan
d m
ea
ns t
ha
t th
ere
is a
nee
d fo
r th
e r
ive
r to
cut
do
wn
aga
in d
urin
g t
he
ne
xt
gla
cia
l: r
etu
rn to
po
int
1 a
bo
ve
).
The
ma
ny g
lacia
l/in
terg
lacia
l cycle
s o
f th
e P
leis
tocen
e o
ften
re
su
lt
in a
se
rie
s o
f a
ltitu
din
ally
-se
pa
rate
d t
err
ace
s in
riv
er
va
lleys:
usu
ally
re
ferr
ed
to
as a
te
rra
ce
sta
irc
as
e. W
he
re th
ere
are
te
rra
ce
s a
t d
iffe
ren
t h
eig
hts
ab
ove
th
e f
loo
dp
lain
(a
s in
th
e E
xe
va
lley),
th
e h
igh
er
terr
ace
s a
re u
su
ally
(b
ut
not
alw
ays)
old
er.
R
ew
ork
ing
of
Pala
eo
lith
ic a
rte
fac
ts:
Pa
laeolit
hic
art
efa
cts
su
ch
a
s s
ton
e to
ols
are
oft
en
fou
nd in
te
rra
ce
de
po
sits w
hic
h w
ere
fo
rmed
in
th
e P
leis
tocen
e.
It is a
ssu
me
d th
at th
e a
rtefa
cts
we
re
left
by h
om
inin
s o
n r
ive
r b
an
ks,
gra
ve
l b
ars
, an
d o
the
r a
rea
s o
f th
e f
loo
dp
lain
, a
nd
we
re t
he
n w
ash
ed in
to t
he r
ive
rs d
urin
g
floo
din
g e
pis
ode
s. T
he a
rtefa
cts
we
re la
ter
dep
osited
alo
ng w
ith
th
e g
rave
ls a
nd
sa
nd
s, a
nd a
re th
ere
fore
ve
ry r
are
ly f
oun
d in t
he
p
lace
wh
ere
th
ey w
ere
dis
ca
rded
by t
he h
om
inin
s.
Ma
p o
f th
e w
alk
R
oute
map p
roduced b
y L
.S. B
asell
(PR
oS
WeB
) usin
g b
ackgro
und g
eolo
gic
al data
repro
duced b
y
perm
issio
n o
f th
e B
ritish G
eolo
gic
al S
urv
ey,
Lic
ence 2
005/0
89 ©
NE
RC
and D
igim
ap d
ata
lic
ensed
to E
xete
r U
niv
ers
ity. A
ll rights
reserv
ed.
Th
is m
ap
is c
op
yri
gh
t an
d n
ot
to b
e r
ep
rod
uced
.
![[Supplementary material] Palaeolithic occupation and](https://img.pdfslide.us/doc/110x75/62761d2ca094c31a4379a58c/supplementary-material-palaeolithic-occupation-and-.jpg)
