High Plains Aquifer Information and Databases:
Large Data Sets for Earth Science and GIS Learning and Skill
Development
P. Allen Macfarlane, B.B. Wilson, and M.A. Townsend
Kansas Geological Survey, University of Kansas, 1930 Constant Ave., Lawrence Kansas 66047
Abstract
Saturated thickness and thickness change over time are important parameters used to model and manage the High Plains aquifer. Insight into how these parameters are
being used for High Plains aquifer management can be found through HiPLAIN (http://www.hiplain.org/). Calculation of these parameters is made possible because of
depth to water measurements taken annually in irrigation and other types of water wells and the driller’s and geophysical logs of the thousands of wells that have been
drilled in the region. These data are readily available over the Internet from HiPLAIN or the Kansas Geological Survey directly (KGS, http://www.kgs.ku.edu/) through the
WIZARD, Water Well Completion Records, Oil and Gas, and other derivative databases.
These large databases represent the collected field observations and experiences of science practitioners (well drillers and field technicians) and thus present
opportunities for learning, 3-D visualization, and skill development, especially the ability to use geographic information systems (GIS) to analyze geospatial data sets
from diverse sources. Using the WIZARD database, students can directly import data into spreadsheet programs to (1) calculate the water-table elevation at each well
measured and (2) create hydrographs showing trends in depth to water at a particular well and determine rates of water-level decline or rise, if there are sufficient
historical data. The driller’s logs in the Water Well Completion Records database and the geophysical logs in the Oil and Gas database must be interpreted to delineate
the depth to the base of the High Plains aquifer from surface. Alternatively, a depth to bedrock database derived from driller’s and geophysical log interpretation has
recently been completed and is on-line at the KGS web site, if working with the driller’s logs is not of interest. Land-surface elevation is generally not reported on these
forms, but can be determined from a digital elevation model using GIS procedures. Depending on its local relief, the elevation of the base of the High Plains aquifer data
can be contoured manually or automatically using a GIS geostatistics package. Saturated thickness and thickness change can then be calculated using one of several
GIS procedures to subtract the bedrock surface from the water-table surface elevation.
Kansas Ogallala/High Plains Aquifer Hydrostratigraphy
The High Plains aquifer consists of Pliocene and Quaternary unconsolidated to partly consolidated alluvial, lacustrine,
and eolian deposits. Lithologically, the aquifer consists of gravel, sand, silt, and clay in proportions that are highly
variable across the western Kansas region. Caliche and silcrete dominated horizons are prominent. In southwest
Kansas, lacustrine limestones and marls occur in the lower part of the section. All of these lithotypes occur as
discontinuous layers of highly variable lateral extent.
Driller’s logs of boreholes to install water wells were analyzed to characterize the distribution of lithologies within the
Ogallala aquifer in two small study areas of northwest Kansas. Each study area was approximately 324 mi2. The
histograms to the left and the scatterplots below illustrate the aquifer’s highly variable lithologic make-up.
Coarse Fraction Thickness =
Aggregate Sand + Aggregate Sand & Gravel
Thickness
Thickness
Caliche & cemented layer occurrence, upper half vs.
lower half in the two study areas
Calculation of Saturated Thickness
Calculation Algorithm
Land Surface Elevation (2000 feet)
Depth to bedrock from
surface estimated using
gamma-ray & driller’s logs
Depth to the water table from
surface estimated from depth
to water measurements taken
during annual surveys of
water wells
Land surface elevation
estimated from digital
elevation models
Water Table Elevation (1950’)
Water Table Elev. – Bedrock Elev. =
Saturated Thickness (150’)
Bedrock Elevation (1800’)
Digital Data Sources from the KGS or HiPLAIN Websites
http://www.kgs.ku.edu/
WIZARD Wells with a
Depth to Water
Measurement in
Ogallala Aquifer
Region of Kansas,
Winter 2002-2004
Bedrock Elevation
Data base in EXCEL
Spreadsheet form
WIZARD
Data Base
Query
Depth to
Water level
Locations of Wells & Boreholes
with Depth to Bedrock Data
Ogallala Portion of the High Plains
Aquifer, Western Kansas &
Surrounding States
http://www.hiplain.org/
HiPLAIN
Data Clearinghouse for all states
In the High Plains Region
Generation of Saturated Thickness Maps Using GIS Procedures
Map of the Elevation of the Water Table in the High Plains Aquifer
generated from the WIZARD well water-level elevations. The watertable surface is generated using automatic contouring and
geostatistical analysis techniques in ARC GIS.
Two methods are available to produce the regional
saturated thickness map of the High Plains aquifer.
The most straight-forward would be to directly
subtract the bedrock-surface elevation surface from
the water-table surface elevation to produce the map.
However, the method used in the map shown above
is to derive estimates of the water-table and bedrock
elevation at the center of each 1 sq. mile section
using interpolation, run the calculation algorithm at
each section center, and then automatically contour
the resulting saturated thickness values.
Values from interpolated surfaces
Elevation contours on the bedrock surface are
generated using manual methods because of its
high local relief. Following manual contouring, the
map was scanned and the contours were imported
into ARC GIS to generate a coverage. The contour
map of the bedrock surface in southwest Kansas is
expanded to show the high local relief on the
bedrock surface. In west-central and northwest
Kansas, the bedrock surface does not display such
high local relief. For these areas using the
automatic or geostatistically based contouring
methods may be more appropriate.
are assigned to a PLSS section centers
Summary
Concerns about depletion of the Kansas High Plains aquifer and management of the remaining resource have brought to the fore the need for up-to-date
information on water-table elevation and saturated thickness changes. Consequently, there is now an abundance of digital, geospatial information with
which it is possible to generate detailed maps of the elevation of the bedrock surface and track changes in the water-table elevation from year to year.
K-16 earth science education is experiencing significant growth with the introduction of geotechnologies, including GIS. The availability of these data
sets the Internet makes them ideal for GIS instruction and skill development. Additionally, these data sets in combination with other information on
HiPLAIN and the KGS websites can be used to conduct meaningful student research on water-resources issues in the High Plains region.