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Preliminary Assessment of Sand Dune Stability
Along a Bioclimatic Gradient, North Central and
Northwestern Oklahoma
Carlos Cordova
Oklahoma State University, Stillwater, OK
Jess Porter
Oklahoma State University, Stillwater, OK
Kenneth Lepper
North Dakota State University
Regina Kalchgruber
North Dakota State University
Gregory Scott
Natural Resources Conservation Service
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Cordova, Carlos; Porter, Jess; Lepper, Kenneth; Kalchgruber, Regina; and Scott, Gregory, "Preliminary Assessment of Sand Dune
Stability Along a Bioclimatic Gradient, North Central and Northwestern Oklahoma" (2005). Great Plains Research: A Journal of
Natural and Social Sciences. Paper 783.
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Great Plains Research 15 (Fall 2005):227-49
© Copyright by the Center for Great Plains Studies, University of Nebraska-Lincoln
PRELIMINARY ASSESSMENT OF SAND DUNE
STABILITY ALONG A BIOCLIMATIC GRADIENT,
NORTH-CENTRAL AND NORTHWESTERN OKLAHOMA
Carlos E. Cordova and Jess C. Porter
Department of Geography
Oklahoma State University
Stillwater, OK 74078
[email protected]
Kenneth Lepper
Department of Geosciences
North Dakota State University, Stevens Hall
Fargo, ND 58105
Regina Kalchgruber
Department of Physics
Oklahoma State University
Stillwater, OK 74078
Gregory Scott
Natural Resources Conservation Service
Stillwater Soil Survey Office, 100 USDA, Suite 206
Stillwater, OK 77074
ABSTRACT-Sandhills of eolian origin and currently active dunes in Oklahoma are located mainly on the northern side of the main rivers. Their longitudinal distribution spans a gradient of annual precipitation ranging from 914
mm in the east to 403 mm in the west. Vegetation types along this gradient
include cross-timbers woodlands in the east and sand-sage and short grasses
in the west. The information presented here is a preliminary assessment of
sand dune dynamics and morphology, soils, and vegetation as the basis for an
ongoing study on past and present processes of sand dune stability. For this
purpose, six areas along the east-west precipitation gradient were selected to
evaluate potential sources of information. Pedostratigraphic data were used
to reconstruct prehistoric landscape-change events and sequential aerial
photographs were used to reconstruct modern processes affecting sand dune
stability in the context of climate change and human agency.
Key Words: bioclimatic gradient, Oklahoma, sand dunes, soils, vegetation,
wind erosion (eolian erosion)
227
228
Great Plains Research Vol. 15 No.2, 2005
Introduction
Sand dunes in Oklahoma occur mainly along the large river valleys that
cross the state from west to east, a pattern common across the Great Plains.
Stabilized and active sand dunes in Oklahoma cover 29,000 km2, approximately
15% of the state's total area, of which only 20.7 km 2 are active sand dunes. Stabilized dunes are fixed by different types of vegetation, including cross-timbers
woodland in the east and sand-sage grassland in the west (Fig. 1). Although the
current surface area of active dunes is minimal, evidence suggests that sand dune
activity during 19th- and 20th-century droughts was more widespread than today
(Melton 1940; Muhs and Holliday 1995; Scott 1999). The most recent period of
widespread dune activity documented by aerial photography occurred at the end
of the 1930s. During the subsequent decades, large tracts of sand dunes have been
stabilized as annual precipitation increased (Rhinewald 2005).
Low precipitation, high evapotranspiration, strong winds, and sparse vegetation cover were the primary causes for sand dune activity in the sand-sage
grassland areas of western Oklahoma during long-term drought periods such as
the 1930s. In contrast, the cross-timbers woodlands, which are the westernmost
woods of North America's eastern deciduous forests have been more effective in
maintaining sand dune stability in eastern and east-central Oklahoma (Fig. 2).
This study is a preliminary assessment of sand dune stability along an eastwest precipitation gradient. Vegetative cover, soils, morphology, and location with
respect to river channels are the main factors considered in examining sand dune
stability in six study areas along the precipitation gradient in north-central and
northwestern Oklahoma (Figs. 1 and 2). This study represents the initial investigation in a long-term research project that attempts to elucidate pertinent variables
of sand dune stabilization in prehistoric and historic periods.
Methods
The initial step of this research involved mapping the areas of eolian sand
in Oklahoma (Fig. 1). The information on this map is based on state soil survey
maps (STATSGO); maps published by Kitts (1959, 1965), Fay (1962, 1965),
Fay and Hart (1978), and Stanley et al. (2002a, 2002b) under the sponsorship of
the Oklahoma Geological Survey; and numerous local studies by Blair (1975),
Meyer (1975), Nayyeri (1979), Robbins (1979), Brady (1989), and Scott (1999).
The areas of sand dunes were further classified into categories based on their
position in the river valleys and the type of stabilizing vegetation. In the process
of mapping eolian sand areas, we identified seven spots with presently active
dunes (triangles in Fig. 1).
1020
103' W
101'
I
I
I
16" 16"
99'
I
100'
I
98'
I
26"
18"
28"
97'
I
30"
32" 34"
96'
36"
[
95'W
I
I
36"40"
42"
-37' N
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Active dunes
A
o
Dune fields larger than 20 ha
C
::l
~
Stable dunes and sand sheets
CI:l
g
~ With cross timbers woodlands
~
With sand sage grassland
)
~ With Shinnery oak grassland
~
on fluvial
terraces
.....
'<
With Shinnery oak grassland
or cross timbers
~
With sand sage grasses
G23
Scattered lunettes
"" '"
)
00 """,,,
Other landforms
<..u..,
Escarpments
STUDY AREAS
J. Cimarron
2. Beaver
Precipitation
!
24"
(610)
Annual precipitation in inches and millimeters
3. Woodward-Harper
4. Woods
5 . Major
6 . Logan-Payne
(:})':I Severe and widespread
o
Less severe and localized
Figure 1. Classification of stabilized sand dunes and sand sheets in Oklahoma based on vegetation cover and location with respect to the main
river valleys. The map also shows the location of the main active sand dune fields and the location of the six areas referred to in this research.
tv
~
Great Plains Research Vol. 15 No.2, 2005
230
103"W
It
m
5000
1500
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
4000
Elevation
3000
2000
1000
CLIMATE
Precipitation (mm)..
101'
102'
I
I
I
100'
99'
I
I
97'
98'
96'
I
I
I
~
ApproXimate
westem limit of
Cross TImbers
"""""""
Area 1 ~
Cimarron
Area 2-
~
,
I
,J
Quercus marilandica (Blackjack oak)
and/or Q. stellata (Post oak)
Grasses
IJ
Artemisia spp. (Sagebrush)
Area~~..oQ m~~ __
Woodward~
A~~a~
Harper
Woods
Area 5 Major
Area 6Logan-Payne
~J'.5'
1000
800
Potential
Evapotranspiration (mm). 600
400
Wind % •
(percentage of time wind
speed is above the
threshold to move sand)
30
20
10
Cities
.............................................
EOLIAN ACTIVITY
Present
.....................................................................
HistOric
SOIL SERIES
Dalhart·Vona Alfisols and AridisOIS-----;:;;;;;;;;:;;;-:===~
Tivoli Entisols
Jester Entisols
.. Dune fields
•
Blowouts and floodplain
ndge dunes
______
--G:;d;;t:i8;;U;;;--------------Goodnight Entisols
Eda Alfisols and Entisols - - - - - - -
Devol
Alfisols _====:--
Nobscot alfisols
Efaula-Dougherty Alfisols
Konawa alfisols - - - - - -
Figure 2. Bioclimatic characteristics of the stabilized sand dune fields along a longitudinal profile in north-central and northwestern Oklahoma.
Six focus areas were selected for the purpose of a general assessment
of geomorphic and biogeographic variations along the east-west precipitation
gradient (Fig. 1; Table 1). Pedostratigraphic description and dating were carried
out only in areas 3 and 5 (Fig. 3). The objective of stratigraphic work in these
two areas was exploratory. Therefore, we did not attempt to establish a regional
chronology, but to explore the potential of pedostratigraphy for reconstructing
processes of sand dune activity and stability in the past.
Optically stimulated luminescence (OSL) and accelerator mass spectrometry (AMS) 14C radiocarbon dating are the techniques used to determine the age
of sections in Areas 3 and 5. OSL and AMS 14C ages for sections in Area 3 are
Preliminary Assessment of Sand Dune Stability
231
TABLE 1
RECENT EOLIAN ACTIVITY IN THE FOCUS AREAS OF THIS STUDY
Wind data
station,
Counties (city)
Sand
mobility
index (M)*
Cimarron
(Boise City)
43.0
1930s and sporadic blowouts afterwards. Some
current blowout activity
in agricultural lands
Sand-sage
grassland
2
Beaver
(Beaver)
46.4
Throughout the 20 th
century, with remarkable
activity in the 1930s.
Parabolic dunes are stabilized. Sporadic blowouts
occur. Transverse dunes
are still active, due to
ATVriding.
Sand-sage
grassland
3
WoodwardHarper
(Woodward)
29.6
1930s blowout. Sporadic
current blowout activity.
Sand-sage
grassland
4
Woods
(Freedom)
31.1
Mainly blowout and
transverse, active through
the 20 th century. Ridge
dune activity near fioodplain. ATV riding keeps
a large area of transverse
dunes active. Parabolic
dunes are stabilized.
Crosstimbers and
Sand plum
shrubs
5
Major
(Fairview)
20.5
Sporadic blowout activity
on old dunes and sand
drifting near the river
channel during the 20 th
century. None visible at
present.
Post and
blackjack
oak crosstimbers with
open areas
of sand plum
shrubs
6
Logan-Payne
(Guthrie)
13.9
None reported.
Post and
blackjack
oak crosstimbers
Area
* Based on Lancaster (1988)
Eolian activity
Vegetation
N
~
v~~ .,
Active sand dunes
l l
~~ ;
o
Stabilized sand dunes and sand sheets
Ie ~ el
Terrace deposits
,
I
LL
L \. l
L L
L
L L
L
L
L
e
l.;.)
:/'
M '
3
L
N
<$i, .
LL
L
: ' E,'
I,: ,::,:,:1 Streambed and floodplain deposits
~
o
~
r,
'/
'~
.~~\t·J :
.
,E'
River channel
. ,I' E-T'
Creeks. tributary streams
, ,T'
E
Gypsum escarpment
.E-T '
WOO 1
' eI
- ,
,'E~T
t
Q
-e-
'T
Soil series
Reservoir
o
Devol
E-l'
'J:
T'
Main highways
@
L
,
. '
~
•
E\Ms', N'
Hanor
N Nobscot
Buckminster
T Tivoli
Ames
J
Jester
/[t / ,
2
3 4
Hajek 1 and 2
mi
Figure 3, Areas 3 (Woodward-Harper), 4 (Woods), and 5 (Major), and locations of studied stratigraphic sections.
::s1
S'
en
~
L
\.. - c.
E Eda
Towns
a
N'
5 mi
~
en
(1)
8::r
~
>-'
VI
~
N
N
o
oVI
Preliminary Assessment of Sand Dune Stability
233
TABLE 2
AMS 14C and OSL AGES FOR SECTIONS IN AREA 3
AMS 14C in bulk sediment
Lab
number
Section, depth
(cm)
Conventional 14C
age (yrBP)
2-0 calibrated result
Beta189465
WMA-l
60-70
2900 ±40 BP
3160-2920 BP
Beta189466
WMA-l
140-150
5690 ± 50 BP
6630-6390 BP
Beta189467
WOO-l
48-52
103.2 + 0.5 pMC*
Post 1950 AD
* percent modern carbon
OSL
Section depth
(cm)
Dose
Dose rate
Age
(yr BP)
WOO-l
70cm
0.61 ± 0.057
2.86 ± 0.14
213 ± 23
reported in Table 2. Ages obtained from sections in Area 5 are reported in Lepper
and Scott (2002, in press).
We made a preliminary assessment of active sand dunes in Little Sahara
State Park (Area 4) using vertical aerial photography to compare the extent of
active sand dunes in 1937 and 1995. Changes in this area are now being studied
and compared to climatic trends for the decades following the 1930s drought.
Normal precipitation and temperature data for the period 1974-2003 were
obtained from the National Climatological Data Center (NCDC) and were used
for most locations. Data for assessing climate trends at Little Sahara State Park
covered the period 1928-2003. Wind-rose data for the period 1994-2003 were
obtained from the nearest Mesonet station located at Freedom, Woods County,
Oklahoma. For the purpose of evaluating sand dune activity at Little Sahara State
Park, sand drift potential (DP), resultant drift potential (RDP), and resultant
drift direction (RDD) were calculated and plotted following the methodology
234
Great Plains Research Vol. 15 No.2, 2005
proposed by Fryberger (1979). The sand mobility index (M) (Lancaster 1998)
was calculated for the six selected areas along the bioclimatic gradient (Table
1). Lancaster's sand mobility index evaluates sand mobility as a function of the
percentage of time that wind is above the threshold for sand transport (W) and
the ratio of precipitation to potential evapotranspiration (P:PE). Thus, the index is
obtained as follows: M = W / P:PE. Subsequently, M values were discussed in the
context of values from other locations in the Great Plains (Muhs and Maat 1993;
Muhs and Holliday 1995).
Geomorphic Settings and Sand Sources
Active and stable sand dune fields in Oklahoma are primarily located on
the northern side of the major rivers. Melton (1940) attributed this locational
pattern to the predominantly southerly wind direction, assuming that most
sands originated from the alluvial deposits in the riverbed. Although this is true
for the ridge dunes along the floodplain, later studies determined that the predominant location on the north sides is rather a result of sand source in Pleistocene and Early- to Middle Holocene alluvial deposits, most of which are located
on terraces along the northern riverbanks (Blair 1975; Meyer 1975; Brady 1989;
Scott 1999; Lepper and Scott 2002). The preponderance of Pleistocene alluvial
terraces on the northern banks responds to the long-term southward migration
of the main river valleys (Madole et al. 1991), which is preconditioned by the
regional southwestward dip of the Permian formations (see geologic profiles in
Fay 1962).
In the Oklahoma Panhandle, the location of sand dune fields with respect to
the main river channels varies. Along the Beaver River in Cimarron County, sand
dunes occur on both sides. Here the sand originates from channel alluvium and
weathered material from the Cretaceous sandstones along the valley (Rothrock
1925; Schoff 1943). Downstream, in Texas and Beaver counties, sand dune fields
predominantly occur on the north bank. Along the Cimarron River in Cimarron
(Oklahoma), Baca (Colorado), and Morton (Kansas) counties, sand dunes fields
occur primarily on the south bank, on the Pleistocene river terraces.
Another common eolian sand setting is on uplands, especially along the
divides between the North Canadian, Canadian, Washita, and North Fork rivers
(Fig. 1). Their origin is still not clear, but some sand dunes and sand sheets seem
to occupy high terraces of Lower and Middle Pleistocene paleochannels of the
Canadian, North Canadian, and Cimarron rivers (Fay 1959, 1962). Therefore,
the likely source of upland sands is the alluvial deposits of high Pleistocene terraces. On the basis of the age of the Lava Creek B Ash, Ward and Carter (1998,
Preliminary Assessment of Sand Dune Stability
235
1999) determined that some high terraces occupying the uppermost areas of
divides between the rivers are older than 0.61 million years.
In Beaver County, in the Panhandle of Oklahoma, upland terraces seem
to have originated from older eolian deposits corresponding to an unnamed
geological unit associated with the Pleistocene Black Water Draw Formation
of New Mexico and the Texas Panhandle (Reeves 1976; Stanley et al. 2002a).
Upland dunes in New Mexico and Texas originated from the sandy facies of the
Pleistocene Black Water Draw Formation (Holliday 1989a). However, Pleistocene eolian deposits overlying the Ogallala Formation in western Oklahoma
have not been thoroughly studied, dated, described, or formally defined. This
makes it difficult to establish direct correlation with similar deposits in other
areas of the Southern Great Plains.
Sand Dune Generations and Paleodata
Previous studies on sand dune deposits in Oklahoma have classified the
different generations of sand dunes based on the soil series assigned to them by
state soil surveys (Brady 1989; Scott 1999). Thus, soil series designations (Jester, Tivoli, Eda, etc.) are merely divisions of dunes by surface soil development
and position within the river valley (Fig. 3). We are using these designations
provisionally as a guide for our research. Future mineralogical, sedimentological, and pedostratigraphic studies will refine the chronological aspects of dune
formation and will help us redefine dune-generation classification.
Jester dunes are sand ridges paralleling the main channel of the North
Canadian and Cimarron rivers. Evolution of the Cimarron River from a braided
stream to a meandering channel and the subsequent rapid growth of vegetation
on its floodplain (Schumm and Lichty 1963) have reduced the amount of available sand for ridge-dune formation along floodplain margins. Therefore, Jester
dunes today are becoming more stable.
Tivoli dunes have parabolic and compound-parabolic shapes and are situated
in the lower river terraces, just above the Jester dunes. The majority of these dunes
seem to have formed from blowouts carved on older dunes. Subsequently, the dune
around the blowout develops into a parabolic dune that moves forward and eventually coalesces with other parabolic dunes to form a compound parabolic dune. They
are characterized mainly by entisols and a cover of sand-sage grassland.
Eda, Devol, and Nobscot dunes are found on higher terraces where they
form rolling sand plains. The natural vegetation on these dunes is cross-timbers,
and soils are often alfisols. However, large tracts of these woodlands have been
turned into pastures and cultivated fields. Toward the eastern part of the gradient,
236
Great Plains Research Vol. 15 No.2, 2005
the Konawa and Dougherty dunes appear to be equivalent in age with the Eda
and Devol dunes.
The Otero and Vona dunes occur only in the Panhandle of Oklahoma.
Otero dunes are parabolic, compound parabolic, and hairpin parabolic dunes
of relatively recent age, possibly the past millennium. Vona dunes are gently
rolling hills formed from older dunes of unknown age and are located on Pleistocene higher terraces.
Unfortunately, knowledge of Quaternary alluvium and eolian sands in
Oklahoma is scant. Pleistocene sand dune deposits have been reported on the
highest terraces and interftuvial surfaces between the major rivers. Thurmond
and Wyckoff (1996, 1998) obtained dates between 9371 ± 97 and 25,970 ± 270
14C yr BP from soils formed in sand dune deposits of the Dempsey Divide, located between the Washita and North Fork rivers (Fig. 1). However, the bulk of
eolian deposits along the main river valleys have been assigned a Holocene age
through relative dating (Blair 1975; Meyer 1975; Brady 1989).
Because of the paucity of chronological data, our research team began a
pilot project focusing on obtaining numerical dates from selected locations in
the stabilized dunes in Areas 3 and 5 (Fig. 3). On the northern side of the North
Canadian River near Woodward, AMS 14C and OSL dates from the WMA-l
section indicate that the Eda dunes began to form sometime around 6000 yr BP
(Fig. 4). The date obtained from the A/C soil horizon at WMA-l section (66306390 calculated yr BP) corresponds to a late phase of destabilization associated
with the dry event recorded in the Great Plains approximately between 6000
and 4000 yr BP (Dean et al. 1996). This dry event destabilized dunes and sand
sheets in Texas and New Mexico (Holliday 1989b; Muhs and Holliday 2001),
southern Kansas (Arbogast and Johnson 1998), and eastern Colorado (Forman
et al. 1992, 1995). A date obtained from another buried A/C horizon at 60-70
cm suggests a period of stability around 3160-2190 calculated yr BP (Fig. 4).
Due to the lack of dated sections in this region, it is not clear if this is a period of
stability that had a broad regional extent. However, this period of stability may
correlate with soil formation dated to 2300 yr BP in sand dunes in south-central
Kansas (Arbogast 1996).
Near the WMA-l section, an OSL date from a Tivoli dune at location
WOO-l dune provided a recent date (213 ± 23 yr BP) (Fig. 4). More recent dune
activity in the area has been documented, as shown by the accumulation of sand
during the 20th century on top of section WOO-I. Numerous cases of young
sand deposits like this one are associated with sand blowouts formed in recent
decades. At the Jake Bluff Site, located about 1.5 km east of the WOO-l section,
a sand deposit similar to the Tivoli dunes is found on top of the stratigraphic
""0
>-1
50
t----=-I_
~
Section WMA-1
C1
3'
3160-2920
s'
po
Most recent eolian activity
and road waste
>-1
'-<
~100
;J>
V>
V>
(1)
V>
V>
3
g
~
Edadune
(1)
"--.
g,
C/J
po
;:s
P-
O
s::
;:s
(1)
0, ,
1
C/J
~
p;
g:
~post1950
~ 50
Ab1
"'-..
;:;:
'-<
Section WOO-1
AC
20th century
eolian sand
213.:!:.23
I
I
100
r,
o
5 METERS
Cal AMS
I
I
"c Years BP
• OSL years BP
tB:;;~~~
~
.
Fence
TIvoIId_
~~~7
------ -
-
--
. _____
~
Figure 4, Stratigraphic profiles in Area 3 (Woodward-Harper), See Figure 3 for locations, AMS
14e
dates reported are 2-() calibrated,
N
W
---.J
238
Great Plains Research Vol. 15 No.2, 2005
sequence. A soil below this sand was dated 500 ± 40 14C yr BP (Bement and
Carter 2004). This suggests that the period of activity that formed the Tivoli
dunes in this area occurred between ca. 500 and 200 yr BP.
In the dune fields of eastern Major County, south of Ames, AMS 14C
and OSL dates illustrate cycles of sand dune deposition and stability (i.e., soil
formation) (Fig. 5). The last period of major dune activity in this area ended
ca. 800-700 yr BP, which correlates with the dry event identified in north and
central Oklahoma by Hall (1982) and Hall and Lintz (1984). However, activity
around 200 yr BP, as in the WOO-I section, was not recorded here. It is possible
that the stabilization period did not occur at this location or was not widespread
enough to become evident in the stratigraphic record.
Sand Dunes, Soils, and Vegetation along a Bioclimatic Gradient
Although most dunes along the bioclimatic gradient are stabilized, the
degrees of sand surface stability vary in relation to vegetation, soil development,
and recent eolian activity. The east-west gradient of precipitation encompasses
583 km (approximately 364 miles), ranging from 914 mm (36 in.) to 403 mm (16
in.) (Fig. 1). Accordingly, stabilized dunes in the eastern half of the bioclimatic
transect are presently covered by cross-timbers vegetation growing on alfisols
of the Nobscot, Eufaula, and Konawa soil series (Fig. 2). Dune fields in the
western half of the study area are covered by sand-sage grasslands growing on
entisols of the Vona, Jester, and Tivoli soil series, or on alfisols of the Eda and
Devol soil series.
The values of potential available moisture, obtained by subtracting potential evapotranspiration from precipitation, show a higher moisture deficit in the
sand dune areas of the western half of the transect. This deficit is manifest in a
less dense vegetation cover that makes soils more susceptible to wind erosion
during the high percentages of time in which winds are above the speed to move
sands. When these values are combined into Lancaster's sand mobility index
(M), it is evident that dune destabilization is more likely to occur in the western
areas (Table 1). Conversely, the surplus of moisture in the eastern areas allows
for conditions conducive to sand stability. These conditions may have prevailed
for centuries to millennia, allowi ng woodlands to become established on former
sand dunes.
The difference between western and eastern dune fields in terms of
stability is portrayed by the examples in Figure 6. The western dune fields of
Area 3 (Woodward-Harper) are in the process of stabilization under scattered
vegetation patches of herbs and shrubs. The moisture deficiency created by
TOP OF DUNE
o
'"0
A
A
A
A
A
~
S·
5'
....
po
100
I,",v
AC
'-<
AC
AC
AC
>-
00
00
(1)
00
00
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(1)
g
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g,
en
300
E
'OVriO-1540 Ab
C
(.)
• 769t60
400
.865t79
500
r-ue-
01275-1070 Ab
Iv
-ue-
Bb
600
Bcb
i"DU.
I"~'~
Btb
-ue-
012800-11950 4Ab
700
HAJEK 1
4Btb
BUCKMINSTER
o
1=
::I
.807t60
A.MES
3Ab
3AC
3C
800
• 828't58
P-
C
Btb
• 82yt71
r- Ue-
po
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• 871-t68
-ue-
'"
• 3330't230
(1)
en
.....
po
g,
~
HAJEK 2
A
Horizon name
•
OSL years BP
-ue-
Unconformity
O
c-
Cal AMS 14C Years BP
SITE NAME
I-
HANO R
Figure 5. Stratigraphy, radiocarbon, and OSL ages for a dune field in Area 5 (Major). See Figure 3 for locations. AMS
2-0" calibrated.
c-
tv
VJ
\0
14C
dates reported are
Great Plains Research Vol. 15 No.2, 2005
240
Area 3
Woodward-Harper
Stabilized parabolic dune
Blowout dune
Late Holocene eolian sand
Older Holocene eolian sand
Area 6
Logan-Payne
Hnlln"'>n<>
eolian sand
Late Pleistocene Perkins Alluvium
Permian red beds
Key to vegetation
Rhus
aromatica
Artemisia
filifolia
!
...
Yucca
glauca
...
Ulmus
amertcana
~~~~;f"=- •
...
Induced
pastures
Prunus
angustifolia
Quercus
martlandlca
•t
...
Celtis
laevigata
1
...
Quercus
stellata
Key to soil series
T
Tivoli
E
Eda
Ko-Do
Figure 6. Models of sand dune morphology and vegetation in Areas 3 and 6.
low precipitation and high evapotranspiration results in a sparse vegetation of
short grasses, principal\y sideoats grama (Bouteloua curtipendula) and buffalo
grass (Buchloe dactyloides), tall grasses such as switchgrass (Panicum virgatum), sagebrush (Artemisia filifolia), and yucca (Yucca glauca). Shrubs and
small trees such as sand plum (Prunus angustifolia) and lemon sumac (Rhus
aromatica) colonize the leeward sides of the dunes. Eastern redcedar (Juniperus virginiana) is not uncommon, but it does not dominate among the shrubs.
Soils in the Tivoli dunes consist mainly of entisols (e.g., Typic and Thermic
Preliminary Assessment of Sand Dune Stability
241
Ustipsamments). Strong winds in this area act rapidly to mobilize sand when
vegetation fails to protect sand dune surfaces. The process of sand dune stabilization in this area can be disrupted by occasional formation of blowout dunes.
In Area 6 (Logan-Payne) sand dunes were stabilized in prehistoric times,
as early-19th-century explorers had reported that these areas were covered with
dense oak vegetation (i.e., the cross-timbers) on the northern bank of the Cimarron River (Irving 1956; Graustein 1967). Although no numerical data exist,
the development of alfisols (e.g., Thermic and Ustic Haplustalfs; Thermic and
Arenic Haplustalfs) with relatively well-developed Bt horizons suggests a longer
period of stability, possibly on the order of millennia. Soils here support a cover
of cross-timber woodlands, although some are cultivated or used as pastures. The
most typical trees of the sandhill cross-timbers in this area are post oak (Quercus
stellata), blackjack oak (Q. marilandica), southern hackberry (Celtis laevigata),
and American elm (Ulmus americana). Higher precipitation levels and relatively
lower potential evapotranspiration help maintain stability by providing a more
dense vegetation cover than is evident in the western study areas (Table 1).
Are Dunes Becoming Stabilized?
Sand dunes in Oklahoma are largely inactive, according to the models produced by plotting time that wind is above the threshold to move sand (W) and the
precipitation-potential evapotranspiration ratio (P:PE) (Fig. 7). Even areas with
currently active dunes such as Little Sahara and Beaver Dunes state parks (study
areas 2 and 4) fall within the inactive class. This suggests that nonclimatic factors
playa significant role in keeping tracts of sand dunes active. In order to test this
assumption, Rhinewald (2005) reconstructed the process of landscape change in
Little Sahara and Beaver Dunes state parks during the last two-thirds of the 20th
century using sequential aerial photography. The reconstruction shows that the
process of sand dune stabilization after the 1930s parallels the slight increase in
annual precipitation, and that most of the areas of current sand dune activity correspond to areas of major sand dune vegetation disturbance, particularly through
ATV (all-terrain vehicle) riding. Nonetheless, despite human disturbance, active
sand dune areas in Little Sahara State Park at present have declined to 75% of
their total area in 1937. In Beaver Dunes State Park, the area of active dunes is
only 12% of their total area in 1941 (Rhinewald 2005).
The case of Little Sahara State Park is perhaps the most interesting regarding factors of sand dune stabilization since the Dust Bowl years (Fig. 8).
Annual and decadal precipitation and potential evapotranspiration patterns in
the past 75 years show a slight increase in moisture (Fig. 9; Table 3). Despite
Great Plains Research Vol. 15 No.2, 2005
242
(A)
100~----------,-----------~
Fully
active
75
~
~50
:=
25
•5.
6
0.00
0.25
0.50
0.75
1.00
PIPE
(8)
100
Largely inactive
75
--
(l)
(l)
>
o
e;:::: 50 -
t5t1l
~
"S
U.
>
u
00
008
o 0
t1l
>,
~o
....
t1l
-l
0
oa:lO
o
g
:>
~o
00 00
00 9
o 0.0 0
0
25
0 0
0 0
0
qJ, c9
•2 1
0
••
4 3
•5.
6
I
0.00
0.25
I
0.50
I
I
0.75
1.00
PIPE
Figure 7. Plots showing the variables of Lancaster's sand mobility index, the amount of
time wind is above the threshold velocity for moving medium sand (W), versus the ratio of
precipitation (P) to potential evapotranspiration (PE) for locations in this study (squares)
and other locations in the Great Plains (dots) according to Muhs and Maat (1993). (A) Dune
activity classes by Lancaster (1988). (B) Modification of (A) showing dune activity classes
based on P:PE values based on Muhs and Maat (1993) and Muhs and Holliday (1995).
Preliminary Assessment of Sand Dune Stability
575
DP
RDP
197
0.34
RDPIDP
Flp
J
TS 1
TS2
T
243
1 kilometer
1 mile
Floodplain
Jester dunes (stabilized in the late 20th century)
Dunes stabilized before 1937
Dunes stabilized after 1937
Tivoli dunes (long stabilized)
Figure 8. Little Sahara State Park dunes. Stabilized dunes and extent of sand dunes in
1937 and 1995. The photograph was taken in 1995.
244
Great Plains Research Vol. 15 No.2, 2005
1300
:i
:E
Z
o
~
'a:::"'
(j
w
0::
Do
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
W'
,,~
r---------------------------------------------------,
............... ANNUAl. ..
.~
POTENTIAL
EVAPOTRANSPIRATION
-- ---------- .. _"---- - ------- --,
- --- --""-------
_. ---."
---"~
_
-"
~
~"J
,,~
Figure 9. Annual precipitation, annual potential evapotranspiration, and March-April precipitation for 1928-2003, registered at Waynoka, OK, north of Little Sahara State Park.
dry periods in the 1950s and 1960s, mean annual precipitation tends to increase.
The most noticeable changes since the mid-1970s are a slight increase in annual rainfall and relatively moderate annual potential evapotranspiration rates
compared to previous decades. Averages for March and April precipitation for
each year were also plotted and compared with annual values because the spring
season is the most critical time of eolian activity during the year in the Southern
Great Plains (Holliday 1991; Stout 2001). A slight increase in March-April precipitation is observed since the late 1960s (Fig. 9; Table 3). This suggests that
moisture is becoming available for grasses and other annual herbs at the time
when winds are the strongest. Therefore, minimal increases in moisture during
the past three decades have led to the reduction of most active dune fields as
they become stabilized with grasses, sage, and shrubs. In view of this potential
scenario, our team is monitoring the seasonal development of vegetation in relation to precipitation. However, at this writing, the first annual cycle of seasonal
data is not yet available.
Another interesting pattern observed at Little Sahara State Park is the
relatively rapid stabilization in areas where ATV riding is not allowed. Some of
these areas had fully active sand dunes in 1937, but now they are vegetated (Fig.
8). Vegetation cover consists mainly of a cover of sages, tall and short grasses,
yuccas, and sand plum shrubs.
Although sand dune stabilization has been increasing in recent decades,
the question of the fate of the dunes in a major drought still lingers. Our current
research aims to collect data to create a predictive model of sand dune destabilization in the event of 1930s-magnitude drought.
Preliminary Assessment of Sand Dune Stability
245
TABLE 3
DECADAL AVERAGES OF ANNUAL PRECIPITATION, POTENTIAL
EVAPOTRANSPIRATION, AND MARCH-APRIL PRECIPITATION
AT WAYNOKA STATION, NORTH OF LITTLE SAHARA STATE PARK
Decade
Annual
precipitation
(mm)
Annual potential
evapotranspiration
(mm)
March-April
precipitation
(mm)
Number
of years of
precipitation
above average*
1931-40
622.3
916.9
99.1
4
1941-50
645.2
796.6
101.6
4
1951-60
609.6
916.9
94.0
4
1961-70
640.1
825.5
86.4
5
1971-80
663.0
901.7
106.7
5
1981-90
617.2
726.4
111.8
6
19912000
668.0
873.7
129.5
8
*Mean annual precipitation (1928-2003) = 655 mm
Conclusions
Sand dunes in north-central and northwestern Oklahoma are located
mainly where the sources of sands are Pleistocene and Early Holocene alluvial
deposits. This setting corresponds to alluvial terraces located mainly on the
northern side of the large rivers. The oldest dunes are located on the highest
river terraces, where preliminary dates show that they formed during the Early
and Middle Holocene. The most recent dunes are located in the lower terraces
and along the main channels. They include dunes ofthe Tivoli soil series which,
according to preliminary chronometric data, formed during the last millennium. Sequential aerial photography shows that the youngest parts of the Tivoli
soil series (TS] and TS) and the ridge dunes along the river channels (Jester soil
series) became stabilized during the second half of the 20th century as is seen
in the area around Little Sahara State Park (Fig. 8).
Our preliminary assessment suggests that sand dune stability patterns are
tied to bioclimatic variations along an east-west precipitation gradient. In the east,
246
Great Plains Research Vol. 15 No.2, 2005
sand dune stabilization has been more effective for the development of oak woods
of the cross-timbers woodlands. No historic dune activity is reported in this area
of Oklahoma, suggesting that sand surfaces are fully stabilized. Even though
some cross-timbers areas have been cleared for cultivation and other economic
activities, there is no destabilization threat, particularly under the current climatic
conditions. Most of the historic and current dune activity, however, has occurred
west of the 98th meridian, where vegetation consists of sand-sage grassland and
scattered shrubs. In these areas, frequent strong winds and low P:PE ratios allow
destabilization, particularly through human disturbance.
The areas of sand dune activity have decreased during the second half
of the 20th century due to a slight increase in precipitation, particularly during
the early spring, when the strongest winds occur. Active dunes persist mainly
in areas where ATV riding occurs, as is the case in Little Sahara State Park.
References
Arbogast, A.F. 1996. Stratigraphic evidence for late-Holocene aeolian sand
mobilization and soil formation in south-central Kansas, U.S.A. Journal
of Arid Environments 35:403-14.
Arbogast, A.F., and W.C Johnson, 1998. Late Quaternary landscape response to
environmental change in south-central Kansas. Annals of the Association
of American Geographers 88:126-45.
Bement, L.C, and B.l Carter. 2004. Trip 4, Stop 6: The Jake Bluff Site: Clovis
bison hunting adaptations at the brink of mammoth extinction on the
Southern Plains of North America. In 18th Biennial Meeting of the American Quaternary Association Guidebook for Fieldtrips, ed. R. Mandel,
4.45-4.42. Lawrence: Kansas Geological Survey.
Blair,lA. 1975. Surficial geology of the Cimarron Valley from Interstate 35
to Perkins, north-central Oklahoma. Master's thesis, Oklahoma State
University, Stillwater.
Brady, R.G. 1989. Geology of the Quaternary dune sands in eastern Major and
southern Alfalfa counties, Oklahoma. PhD diss., Oklahoma State University, Stillwater.
Dean, E.W., T.S. Ahlbrandt, RY. Anderson, and J.P. Bradbury. 1996. Regional aridity in North America during the middle Holocene. The Holocene 6:145-55.
Fay, R.O. 1959. Pleistocene course of the south Canadian River in central western Oklahoma. Oklahoma Geology Notes 19: 3-12.
Fay, R.O. 1962. Part I. Stratigraphy and general geology of Blaine County. In
Geology and Mineral Resources of Blaine County, Oklahoma, 12-99,
Oklahoma Geological Survey Bulletin 89.
Preliminary Assessment of Sand Dune Stability
247
Fay, R.O. 1965. Geology and Mineral Resources of Woods County, Oklahoma.
Oklahoma Geological Survey Bulletin 106.
Fay, R.O., and D.L. Hart, Jr. 1978. Geology and Mineral Resources (Exclusive
of Petroleum) of Custer County, Oklahoma. Oklahoma Geological Survey Bulletin 114.
Forman, S.L., A.F.H. Goetz, and R.H. Yuhas. 1992. Large scale stabilized dunes
on the High Plains of Colorado: Understanding the landscape response to
Holocene climates with the aid of images from space. Geology 20:145-48.
Forman, S.L., R. Oglesby, Y. Makgraf, and T. Stafford. 1995. Paleoclimatic significance of Late Quaternary eolian deposition on the Piedmont and High
Plains, Central United States. Global and Planetary Change 11:35-55.
Fryberger, S.G. 1979. Dune forms and wind regime. In A Study of Global Sand
Seas, ed. E.D. McKee, 137-69. Washington, DC: United States Geological
Survey, Geological Survey Professional Paper 1052.
Graustein, IE. 1967. Thomas Nu tta I, Naturalist: Explorations in America,
1808-1841. Cambridge, MA: Harvard University Press.
Hall, S.A. 1982. Late Holocene paleoecology of the Southern Plains. Quaternary Research l7:391-407.
Hall, S.A., and C. Lintz. 1984. Buried trees, water table fluctuations, and 3000
years of changing climate in West-Central Oklahoma. Quaternary Research 22:129-33.
Holliday, Y.T. 1989a. The Blackwater Draw Formation (Quaternary): A 1.4plus-m.y. record of eolian sedimentation and soil formation on the Southern High Plains. Geological Society of America Bulletin 10l :1598-1607.
Holliday, Y.T. 1989b. Middle Holocene drought on the southern High Plains.
Quaternary Research 31 :74-82.
Holliday, Y.T. 1991. The geological record of wind erosion, eolian deposition,
and aridity on the Southern High Plains. Great Plains Research 1:6-25.
Irving, W. 1956. A Tour of the Prairies, ed. IF. McDermott. Norman: University
of Oklahoma Press.
Kitts, D.E. 1959. Cenozoic of Roger Mills County. Oklahoma Geological Survey Circular 48.
Kitts, D.E. 1965. Geology of the Cenozoic Rocks of Ellis County Oklahoma.
Oklahoma Geological Survey Circular 69.
Lancaster, N. 1988. Development oflinear dunes in the southwestern Kalahari,
southern Africa. Journal of Arid Environments 14:233-44.
Lepper, K., and G.F. Scott. 2002. Late Holocene episodic aeolian activity and
landscape development in the Cimarron River valley, western Oklahoma.
In Proceedings of ICARSIGCTE-SEN Joint Conference, 463-66. Lubbock, TX: Center for Arid and Semiarid Lands Studies.
248
Great Plains Research Vol. 15 No.2, 2005
Lepper, K., and G.F. Scott. In press. Late Holocene aeolian activity in the
Cimarron River Valley of Western Oklahoma. Geomorphology.
Madole, R.F., C.R. Ferring, M.l Guccione, S.A. Hall, w.e. Johnson, and C.l
Sorenson. 1991. Quaternary geology of the Osage Plains and Interior
Highlands. In Quaternary Non-Glacial Geology; Conterminous U.S.,
ed. R.B. Morrison, 503-46. Boulder, CO: Geological Society of America,
Geology of North America K-2.
Melton, E.A. 1940. A tentative classification of sand dunes and its application to
dune history in the Southern High Plains. Journal of Geology 48:113-74.
Meyer, G.D. 1975. The surficial geology of the Guthrie North Quadrangle,
Logan County, Oklahoma. Master's thesis, Oklahoma State University,
Stillwater.
Muhs, D.R., and y.T. Holliday. 1995. Evidence of active dune sand on the Great
Plains in the 19th century from accounts of early explorers. Quaternary
Research 43:198-208.
Muhs, D.R., and Y.T. Holliday. 2001. Origin of late Quaternary dune fields on
the Southern High Plains of Texas and New Mexico. Geological Society
of America Bulletin 113:75-87.
Muhs, D.R., and Maat, P.B. 1993. The potential response of eolian sands to
greenhouse warming and precipitation reduction on the Great Plains of
the U.S.A. Journal of Arid Environments 25:351-61.
Nayyeri, C. 1979. Surficial geology of Cimarron River valley from one mile east
of Perkins eastward to Oklahoma Highway 18, north-central Oklahoma.
Master's thesis, Oklahoma State University, Stillwater.
Reeves, e.e., Jr., 1976. Quaternary stratigraphy and geologic history of the southern Great Plains. In Quaternary Stratigraphy of North America, ed. W.e.
Mahaney, 213-34. Stroudsberg, PA: Dowden, Hutchinson, and Ross Inc.
Rhinewald, e. 2005. Sand dune stabilization patterns in Little Sahara and
Beaver Dunes state parks in relation to climate change and recreational
activities. Master's thesis, Oklahoma State University, Stillwater.
Robbins, G.D. 1979. Geology of the Yale Southwest Quadrangle, Payne County,
Oklahoma. Master's thesis, Oklahoma State University, Stillwater.
Rothrock, E.P. 1925. Geology of Cimarron County, Oklahoma. Oklahoma Geological Survey Bulletin 34. Norman: Oklahoma Geological Survey.
Schoff, S.L. 1943. Geology and Ground Water Resources of Cimarron County,
Oklahoma. Oklahoma Geological Survey Bulletin 64. Norman: Oklahoma Geological Survey.
Preliminary Assessment of Sand Dune Stability
249
Schumm, S.A., and R.w. Lichty. 1963. Channel Widening and Flood-Plain
Construction along the Cimarron River in Southwestern Kansas. Washington, DC: US. Government Printing Office, US. Geological Survey
Professional Paper 352-D.
Scott, G. 1999. Aeolian modification of Pleistocene terraces along the Cimarron River in Major County, Oklahoma. Master's thesis, Oklahoma State
University, Stillwater.
Stanley, T.M., N.H. Suneson, and G.R. Standridge. 2002a. Geologic map of the
Beaver 30' x 60' Quadrangle, Beaver, Ellis, Harper, and Texas Counties,
Oklahoma. Scale 1: 100,000. Norman: Oklahoma Geological Survey.
Stanley, T.M., N.H. Suneson, and G.R. Standridge. 2002b. Geologic map of
the Guymon 30' x 60' Quadrangle, Texas County, Oklahoma. Scale
1: 100,000. Norman: Oklahoma Geological Survey.
Stout, lE. 2001. Dust and environment in the Southern High Plains of North
America. Journal of Arid Environments 47:425-41.
Thurmond, J.P., and D.G. Wyckoff. 1996. A dated eolian soil sequence on the
Dempsey Divide. Newsletter of the Oklahoma Anthropological Society
44:6-8.
Thurmond, J.P, and D.G. Wyckoff. 1998. Late Pleistocene dunes along the
Dempsey Divide. Current Research in the Pleistocene 15:139-43.
Ward, P.A., III, and B.J. Carter 1998. Paleopedologic interpretations of soils
buried by Tertiary and Pleistocene-age volcanic ashes: South-central
Kansas, western Oklahoma, and northwestern Texas, US.A. Quaternary
International 51/52:213-21.
Ward, PA., III, and B.J. Carter. 1999. Rates of stream incision in the middle
part of the Arkansas River basin based on late Tertiary to mid-Pleistocene
volcanic ash. Geomorphology 27:205-28.
250
Great Plains Research Vol. 15 No.2, 2005
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