1

U.S. Department of the Interior

U.S. Geological Survey

Open-File Report 2011-1037

February 2011 Printed on recycled paper

Multiple Technologies Applied to Characterization of the 

Porosity and Permeability of the Biscayne Aquifer, Florida

Irregular topography on karstic upper surface of the Miami Limestone in Miami-Dade County shows an example of highly macroporous oolitic limestone. 

The macroporosity is related to an Ophiomorpha-dominated ichnofabric. The sample shown in figure 5 was collected at this site. Photograph by Kevin 

Cunningham, USGS. Terms defined in the glossary are shown in boldface type where first used in the text.

where it extends eastward from the Ever

R 

 esearch is needed to determine how seepage-control actions planned by the Comprehensive Everglades Restoration 

 Plan (CERP) will affect recharge, groundwater flow, and discharge within the dual-porosity karstic Biscayne aquifer 

glades to Biscayne Bay. A key issue is whether the plan can be accomplished 

without causing urban flooding in adjacent populated areas and diminishing coastal freshwater flow needed in the 

restoration of the ecologic systems. Predictive simulation of groundwater flow is a prudent approach to understanding 

hydrologic change and potential ecologic impacts. A fundamental problem to simulation of karst groundwater flow is how 

best to represent aquifer heterogeneity. Currently, U.S. Geological Survey (USGS) researchers and academic partners are 

applying multiple innovative technologies to characterize the spatial distribution of porosity and permeability within the 

Biscayne aquifer.
2

Figure 1.  Generalized location of (A) pilot seepage feature 

(yellow bar) to be constructed for the L-31N (L-30) Seepage 

Management Pilot Project, (B) cross-section A–A’ shown in 

figure 3, and (C) map area in (B) and extent of Biscayne aquifer.

N

N

1 KILOMETER

G-3849 G-3871

G-3870 G-3869

G-3848

G-3850

G-3795

G-3849

G-3871

G-3870

G-3869

G-3848

250 METERS

B

A

A

 ́

A

Map

area

in B

C

Biscayne aquifer

Biscayne Aquifer Pore and Permeability Network

Ichnology

Ichnology is the study of trace fossils, which are structures 

that were produced in sedimentary rock or other substrate by 

the activity or growth of organisms (Bromley, 1996). Examples 

of trace fossils include footprints produced by dinosaurs and 

burrows made by worms.

The hydrologic properties of carbonate aquifers are highly 

variable, most notably in their heterogeneous permeability 

(Brahana and others, 1988). The Biscayne aquifer comprises 

karst carbonate rocks having a heterogeneous and anisotropic 

pore network with a range of measured permeability values 

that is at least 13 orders of magnitude (Cunningham and others, 

2004, 2006a,b; 2009). The Biscayne aquifer is considered a 

dual-porosity system (Renken and others, 2008; Cunningham and 

others, 2009), because it consists of (1) matrix porosity (interparticle pores and separate vugs), which provides much of the 

groundwater storage; and (2) touching-vug macroporosity, which 

can create stratiform, areally extensive, groundwater flow pathways and less commonly observed bedding-plane and cavernous 

vugs, vertical solution pipes, and solution-enlarged fractures.

Groundwater flow in the Biscayne aquifer is particularly 

difficult to characterize because of a broad range in pore size and 

complicated pore connectivity. A diverse permeability network 

represents a significant challenge to the accurate simulation of 

dual-porosity karst groundwater flow. State-of-the-art technologies, including ichnologic, cyclostratigraphic, borehole 

geophysical, and computational methods, are being utilized by 

USGS scientists and their colleagues to accurately conceptualize 

and simulate groundwater flow through the Biscayne aquifer.

Ichnology has recently emerged as an important applied 

science in the field of petroleum geology, because bioturbation 

(disturbances in sedimentary rocks generated by organisms) can 

play a significant role in the hydraulic properties of hydrocarbonbearing sedimentary units (Pemberton and Gingras, 2005). 

However, the use of ichnology in hydrology has been rare. 

Nevertheless, the USGS has recently been successful in applying 

ichnology to enhance carbonate aquifer characterization and 

map groundwater flow zones when it is integrated with other 

data types and characterization methodologies (Cunningham 

and others, 2006a,b; 2009). In some of the carbonate rocks 

of the Biscayne aquifer, fossilized burrows have a dominant 

presence where concentrated groundwater flow occurs within 

extremely permeable, vuggy passageways of the aquifer. Most 

of these burrows were likely created by callianassid shrimp 

(Shinn, 1968; Curran and Martin, 2003) during and shortly after 

deposition of carbonate sediments in a shallow, tropical marine 

environment. The fossil burrows that have a pelletal lining are 

named Ophiomorpha.

The USGS is applying the science of ichnology to hydrologic 

questions related to the CERP L-31N (L-30) Seepage Management 

Pilot Project (fig. 1) and to other Biscayne aquifer studies. The 

CERP project, designed to resolve critical uncertainties associated 

with seasonally managing seepage flows, is located within one of 

the most transmissive parts of the Biscayne aquifer (U.S. Army 

Corps of Engineers, 2010). Borehole geophysical data acquired 

by the USGS demonstrate that the very high transmissivities are 

related to bedded macroporous zones of intensely burrowed limestone (figs. 1-3). Delineating the continuity and lateral extent of 

these borrowed flow units is important to the conceptualization of 

groundwater flow at the site, and could be very useful in design and 

interpretation of aquifer performance tests and tracer tests (Renken 

and others, 2005, 2008; Cunningham and others, 2006a).

Cyclostratigraphy

Sequence stratigraphy is a newer conceptual advance in the 

expansive field of sedimentary geology (Miall, 1995), and has transformed the methodology of stratigraphic analysis. High-frequency 

cycles (HFCs) are the fundamental building blocks of sequence stratigraphy and often occur as discernable, repetitive vertical changes 

in lithostratigraphy. The delineation and use of HFCs for correlation 

is cyclostratigraphy. A cyclostratigraphy comprised of four types 

of ideal cycles has been described for the Miami Limestone and 

Fort Thompson Formation, which compose most of the Biscayne 

aquifer (Cunningham and others, 2009). In the context of these ideal 

cycles, stratiform zones of densely packed Ophiomorpha have a 

predictable pattern in their vertical arrangement. 

Concentration of Ophiomorpha in macroporous, extremely 

permeable zones in lower to middle parts of HFCs is common 

in upward-shallowing subtidal and upward-shallowing paralic 

cycles (figs. 2 and 3)—the dominant ideal cycle types of the 

Fort Thompson Formation (Cunningham and others, 2009). 

Specific physical characteristics of the tops and bottoms of 

the cycles, and the vertical and lateral arrangement of their 

lithostratigraphy and paleoenvironments provide a means for 

correlation and mapping of the macroporous and highly permeabable parts of the cycles. Thus, cyclostratigraphy can provide a 

realistic framework for hydrogeologic conceptual models when 

it is used as input for groundwater-flow simulations.
3

Figure 2.   Interpreted flow zones from digital optical 

borehole images and flowmeter, temperature, and conductivity 

measurements acquired in corehole G-3871 at the L-31N (L-30) 

Seepage Management Pilot Project (figs. 1 and 3).

Flow zone–Bedding plane vuggy 

Flow zone–Ophiomorpha-related porosity

macroporosity

Temperature Flow zones

24 0 modeled from Caliper C 26 flowmeter

Conductivity measurements

0

0 1800 3600 10 cm 30 400 μScm -1 700 0 % 100

5e

7

9

Biscayne aquifer

11

HU

MIS

IDEAL CYCLES

SEA LEVEL

NGVD 29 Altitude, in meters

2

-2

-4

-6

-8

-10

-12

-14

Digital 

optical

borehole

image

Upward-shallowing paralic cycle

Upward-shallowing peritidal cycle

Upward-shallowing subtidal cycle

Flow zone Aggradational subtidal cycle

High-frequency cycle top

IDEAL

CYCLES

1

-1

-3

-5

-7

-9

-11

-13

-15

EXPLANATION

HU Hydrogeologic unit 

MIS Marine isotope stage 

NGVD 29 National Geodetic Vertical 

Datum of 1929

Borehole Geophysics

Rock-core recovery using traditional coring procedures 

generally is problematic in more delicate macroporous, vuggy, 

groundwater flow zones. For these reasons, the USGS uses 

groundwater wells as a subsurface laboratory. Innovative logging 

tools provide reliable data on the physical properties of the rocks, 

water quality, and fluid flow within the subsurface borehole 

environment (Wacker and Cunningham, 2008). The USGS digital 

optical borehole imaging tool is markedly useful, because it offers 

a high-resolution image of the borehole wall and cross-sectional 

photo map of the macropore network (figs. 2 and 3). Cunningham 

and others, (2006a, b) have shown that the combination of 

digital image logs, caliper logs, water-quality logs (conductivity 

and temperature), and flowmeter measurements are effective in 

evaluating concentrated groundwater flow (figs. 2 and 3). 

Borehole flowmeters measure vertical flow within a single 

well, and the data used to identify areas of inflow into or outflow 

from the borehole. Differences in hydraulic head produce vertical 

flow within the borehole, which is measured by the flowmeter. 

Interpreted results from flowmeter data combined with other log 

data from the coreholes shown in figure 3 indicate that vertically 

stacked, multistoried layers of macroporous Ophiomorphadominated zones form an extremely transmissive aquifer 

(especially in the lower part of the HFCs) over a lateral distance 

of at least 8.4 kilometers (fig. 3). The broad continuity of the 

permeable zones depicted in figure 3 corroborates the conclusions, reported by Renken and others (2005), Cunningham and 

others (2006a,b; 2009), Renken and others (2008), and Shapiro 

and others (2008), that highly permeable zones of touching-vug 

macroporosity related to burrowing can form principal passageways for concentrated groundwater flow in the Biscayne aquifer. 

Computational Methods

The permeability of touching-vug macroporosity networks 

in carbonate rocks is exceedingly difficult to measure with 

traditional permeameter methodology. This is due to flow-rate 

limitations of the apparatus and issues related to imposing and 

maintaining the extremely small gradients needed to sustain 

Darcian flow regimes during operation of the instrumentation. 

Unfortunately, the upper range of accurate measurements of 

whole-core permeability using the permeameter method does 

not exceed about 10 to 30 Darcies, or about 0.0001 to 0.0003 

meter per second (Cunningham and others, 2009). The inability 

to obtain large permeability values from permeameter measurements of macroporous limestone samples impedes core-scale 

hydrologic characterization. Frequently used for computational 

modeling of small-scale fluid flow, Lattice Boltzmann methods 

(LBM; Sukop and Thorne, 2006) are ideally suited for accurate 

core-scale calculation of the exceptionally high permeabilities

of the Biscayne aquifer, which can be much larger values than a 

permeameter can measure. Figure 4 shows that permeability of 

Biscayne aquifer Ophiomorpha-related macropore networks can 

be 3 to 6 orders of magnitude larger than permeameter-based 

measurements. LBM simulations closely conform to analytical 

solutions for pipe flow, providing the impetus and justification 

for its application to carbonate macropore systems.
4

Figure 3.  Hydrogeologic cross-section in the area of the L-31N (L-30) Seepage Management Pilot 

Project (fig. 1). (A) Hydrologic units, geologic units, marine isotope stages, high-frequency cycles, 

ideal cycles, and correlation of zones of matrix porosity and zones of macroporosity related to either 

bedding-plane vugs or Ophiomorpha-dominated ichnofabric, and where preferential flow within the 

vuggy zones is confirmed by flowmeter measurements (red and yellow arrows).  

(B) Touching-vug macropority related to an Ophiomorpha-dominated ichnofabric. 

G-3795 G-3850 G-3849 G-3871 G-3870 G-3869 G-3848

5e

ML

7

9

?

YNE AQUIFER BISCA

PLEISTOCENE

FORT THOMPSON FORMATION

?

? ?

11

8.43 km

HU

EPOCH

FM

MIS

IDEAL

CYCLES

SEA LEVEL

NGVD 29 Altitude, in meters

SU

PLIO

TF

Casing Casing

No No

DOBI DOBI

Data Data

South North

1.01 km 0.66 km 0.12 km 0.12 km 0.08 km 6.78 km

No Casing Casing Casing Casing DOBI Data No No No No

DOBI DOBI DOBI DOBI

Data Data Data Data

A L-31N (L-30) SMPR

B

10 CENTIMETERS

NGVD 29

2

-2

-4

-6

-8

-10

-12

-14

-16

A A ́

EXPLANATION

ML Miami Limestone Upward-shallowing paralic cycle

SU Semiconfining unit Upward-shallowing peritidal cycle TF Tamiami Formation

Upward-shallowing subtidal cycle DOBI Digital optical borehole image

FM Formation Aggradational subtidal cycle

HFC High-frequency cycle Hydrostratigraphic zone dominated HU Hydrogeologic unit by Ophiomorpha-related MIS Marine isotope stage macroporosity PLIO Pliocene HFC boundary–Dashed where uncertain SMPR Seepage Management Pilot Project Base of Biscayne aquifer–Dashed National Geodetic Vertical Datum where uncertain of 1929

Flow zone–Ophiomorpha-related Flow zone–Bedding plane vuggy 

 macroporosity porosity

IDEAL

CYCLES

1

-1

-3

-5

-7

-9

-11

-13

-15
5

2040

759

1 x 108

731

U V V 1 x 107

319

H 1 x 106

H V

319

V 1 x 105

H

1 x 104

H 1 x 103

1 x 102

H

Permeability (Darcies)

V

1 x 101

V

SHR-1 ML-1 1 x 100

C100 H -Q5e-1 H G-3837-22 G-3837-18

EXPLANATION

U Unoriented permeability LBM calculated permeability

H Horizontal permeability Measured air permeability

V Vertical permeability 319 Sample volume (cm3)

LBM Lattice Boltzmann methods

Figure 4. Lattice Boltzmann methods and air-permeameter 

values derived from limestone samples with macropore networks 

related to abundant Ophiomorpha. 

Computation of intrinsic permeability of core-scale 

macroporous limestone samples from the Biscayne aquifer 

requires virtual renderings, essential for reconstruction of the 

vuggy flow network observed in rock samples. High-resolution 

X-ray computed tomographic (CT) scans of rock samples 

provide a digital sample that is the basis for calculating intrinsic 

permeability (figs. 5 and 6). The rock matrix is assumed to 

be a nonporous medium, and permeability is only measured 

within the network of macropores. Intrinsic permeabilities 

derived from LBM range from 1.5 x 104

 to 2.7 x 107 Darcies for 

Ophiomorpha-related macroporosity (fig. 4). LBM measurements in figure 4 should approximate the range in permeabilities of the flow zones identified in figure 3 using digital 

optical images and flowmeter measurements. Research is in 

progress to investigate the validity of the conceptual assumption 

that core-scale LBM calculated intrinsic permeability values 

are representative of field-scale pore networks. LBM also is 

being used to determine whether ambient flow is laminar or 

turbulent. Non-Darcian effects are of considerable interest if 

they occur under field-scale conditions (Shoemaker and others, 

2008). Sukop and others (2008) concluded that non-Darcian 

behavior due to inertial flow under field-scale gradients could 

effectively reduce the apparent hydraulic conductivity within 

well-connected macroporosity by nearly 50 percent. Future 

LBM groundwater flow simulations will examine the impact of 

non-Darcian flow on field-scale hydraulic conductivity. 

Predicting where concentrated groundwater flow occurs 

is important, especially in areas that have not yet been investigated by coring and logging methodologies. Therefore, 

experimentation with spatial prediction is being conducted 

through the use of variograms, a quantitative descriptive 

statistical tool that can be used graphically to characterize 

spatial continuity. Digital images of borehole walls (fig. 7A) are 

used to create approximately 0.2-meter-wide 3-D renderings 

of carbonate macroporosity. A thresholding process is used 

to partition the digital imagery into macropores and nonpermeable rock matrix (fig. 7B). Three-dimensional coordinate 

information is extracted that defines the presence or absence 

of rock matrix at individual image pixels of the borehole wall. 

Variograms for the 3-D data are computed, and a 3-D simulation is created of a volume comprised of only two components: 

macroporosity and rock matrix (fig. 7C). 

Experimentation with this methodology (Sukop and others, 

2008) may extend the use of variograms to predict flow-zone 

continuity between wells. A major goal of this work is to use 

LBM to simulate field-scale groundwater flow, providing an 

alternative to continuum models based on equivalent porous 

media flow.

5 CENTIMETERS

Figure 5. Sample of highly porous oolitic Miami Limestone 

that displays visible limestone macroporosity related to an 

Ophiomorpha-dominated ichnofabric. Photograph by Richard 

Wescott, USGS. 

2 CENTIMETERS

Figure 6.  Computer rendering created from sample SHR-1 

(fig. 5) collected at an outcrop of the Miami Limestone (cover 

photo). The limestone macroporosity is related to a Ophiomorphadominated ichnofabric. Light-blue areas represent rock matrix 

and darker areas macroporosity. LBM-calculated permeability of 

the macroporosity (78 percent) is 2.7x107

 Darcies (fig. 4). CT-scan 

acquired at the High-Resolution X-Ray CT Facility at the University 

of Texas. 
6

Figure 7.  (A) Borehole wall image from the G-3849 well (figs. 1 

and 3). Darker areas are carbonate macroporosity related to 

an Ophiomorpha-dominated ichnofabric. (B) 3-D threshold data 

of image in (A) where blue areas are macroporosity and white 

areas are matrix porosity. (C) Enhanced simulation of 3-D volume 

rendering in (B) based on borehole-image variogram. 1 METER

64 CENTIMETERS

A B C

20 CENTIMETERS 20 CENTIMETERS

20 CENTIMETERS

Conclusions

A major challenge to evaluating groundwater flow in the 

Biscayne aquifer is characterizing and simulating the complex 

geometry of its porosity and permeability networks. The USGS 

has expanded its integrated use of ichnology, cyclostratigraphy, 

borehole geophysics, and computational methods to characterize the Biscayne aquifer between the Florida Everglades 

and Biscayne Bay. The motivation of this research is to better 

understand the hydraulic properties of the Biscayne aquifer 

and to upscale core- and borehole-scale hydrogeologic characterizations to a field-scale conceptualization. An example 

of application of this research strategy is at the L-31N (L-30)

Seepage Management Pilot Project site, underlain by one 

of the most transmissive parts of the Biscayne aquifer. The 

exceptionally large transmissivity in this area is attributed to a 

limestone sequence of multistoried Ophiomorpha-dominated 

groundwater flow zones comprised of vuggy macroporosity 

that are compartmentalized within high-frequency cycles. This 

conceptualization of Biscayne aquifer macroporosity is a shift 

from earlier conceptualizations of the aquifer as an equivalent porous medium. Maps showing the spatial continuity of 

highly permeable flow zones are being developed to improve 

modeled conceptualization of groundwater flow. Ultimately, 

this information will be used to aid sustainable use, protection, 

Large cave that formed in the Miami Limestone where it is dominated by a stratiform Ophiomorpha ichnofabric (fig. 4; from Cunningham and 

others, 2008).  Photograph by Alan Cressler, USGS.
7

Glossary

Cyclostratigraphy—The study of stratified rock in relation to cyclic formation and destruction.

Ichnofabric—All aspects of the texture and internal structure of a substrate that result from bioturbation and bioerosion on all scales 

(Ekdale and Bromley, 1983; Bromley and Ekdale, 1986).

Ideal cycle—A sedimentary cycle that includes both stages of a rise and fall of relative sea level, in which the interplay of relative sealevel change and sediment supply or production results in a predictable arrangement of vertical lithofacies (see Helland-Hansen, 2009).

High-frequency cycle—The smallest set of sediment deposited during a single relative rise and fall in sea level.

Vug—A “pore space that is within grains or crystals or that is substantially larger than grains or crystals,” but does not include interparticle 

pore space (Lucia, 1995). Vugs are commonly present as leached fossils or other grains, fractures, and large, irregular cavities.

and restoration of the Everglades and other ecosystems within 

the region. Lattice Boltzman methods and new geostatistical 

approaches are offering practical approaches to the delineation of 

karst carbonate heterogeneity and the understanding of concentrated groundwater flow within the Biscayne aquifer.

By Kevin J. Cunningham and Michael C. Sukop

References Cited

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1988, Carbonate rocks, in Back, W. Rosenshein, J.S., and 

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Bromley, R.G., 1996, Trace fossils: Biology, taphonomy and 

applications (2d ed.): London, Chapman & Hall, 361 p. 

Bromley, R.G., and Ekdale, A.A., 1986, Composite ichnofabrics and tiering of burrows: Geological Magazine, v. 123, 

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Cunningham, K.J., Carlson, J.L., Wingard, G.L., Robinson, 

Edward, and Wacker, M.A., 2004, Characterization of aquifer 

heterogeneity using cyclostratigraphy and geophysical methods in the upper part of the karstic Biscayne aquifer, southeastern Florida: U.S. Geological Survey Water-Resources 

Investigation Report 03-4208, 46 p.

Cunningham, K.J., Renken, R.A., Wacker, M.A., Zygnerski, 

M.R., Robinson, Edward, Shapiro, A.M., and Wingard, G.L., 

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in the karst limestone of the Biscayne aquifer, SE Florida, in

Harmon, R.S., and Wicks, C., eds., Perspectives on karst geomorphology, hydrology, and geochemistry—A tribute volume 

to Derek C. Ford and William B. White: Geological Society 

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Cunningham, K.J., Sukop, M.C., Huang, H., Alvarez, P.F., 

Curran, H.A., Renken, R.A., and Dixon, J.F., 2009, Prominence of ichnologically influenced macroporosity in the 

karst Biscayne aquifer: stratiform “super-K” zones: 

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Cunningham, K.J., Sukop, M.C., Huang, H., Alvarez, P.F., 

Curran, H.A., Wacker, M.A., Florea, L.J., Renken, R.A., and 

Dixon, J.F., 2008, Biogenic macroporosity and its lattice 

Boltzmann method permeability in the karst Biscayne aquifer, in Sasowsky, I.D., Feazel, C.T., Mylroie, J.E., Palmer, 

A.N., and Palmer, M.V., eds., Karst from Recent to Reservoirs: Special Publication 14, Karst Waters Institute Proceedings, Leesburg, VA, p. 30-35.

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J.F., and Wingard, G.L., 2006b, A cyclostratigraphic and 

borehole geophysical approach to development of a threedimensional conceptual hydrogeologic model of the karstic 

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Bahamas: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 192, p. 229-245.

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Lucia, F.J., 1995, Rock-fabric/petrophysical classification of 

carbonate pore space for reservoir characterization: American 

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8

For more information on the USGS—the 

Federal source  for science about the 

Earth, its natural and living resources, 

natural hazards, and the environment: 

World Wide Web: http://www.usgs.gov 

Telephone 1-888-ASK-USGS

Any use of trade, product or

firm names is for descriptive

purposes only and does not

imply endorsement by the

U.S. Government

8

Miall, A.D., 1995, Whither stratigraphy?: Sedimentary Geology, 

v. 100, p. 5–20.

Pemberton, S.G., and Gingras, M.K., 2005, Classification and 

characterizations of biogenically enhanced permeability: 

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89, no. 11, p. 1493-1517.

Renken, R.A., Cunningham, K.J., Shapiro, A.M., Harvey, 

R.W., Zygnerski, M.R., Metge, D.W., and Wacker, M.A., 

2008, Pathogen and chemical transport in the karst limestone 

of the Biscayne aquifer: 1. Revised conceptualization of 

groundwater flow, Water Resources Research 44, W08429, 

doi:10.1029/2007WR006058.

Renken, R.A., Shapiro, A.M., Cunningham, K.J., Harvey, 

R.W., Metge, D.W., Zygnerski, M.R., Wacker, M.A., Osborn, 

C.L., and Ryan, J.N., 2005, Assessing the vulnerability of 

a municipal well field to contamination in a karst aquifer: 

Environmental Engineering Geoscience Journal, v. 11, no. 4, 

p. 341-354.

Shapiro, A.M., Renken, R.A., Harvey, R.W., Zygnerski, M.R., 

and Metge, D.W., 2008, Pathogen and chemical transport 

in the karst limestone of the Biscayne aquifer: 2. Chemical 

retention from diffusion and slow advection: Water Resources 

Research, v. 44, W08430, doi:10.1029/2007WR006059.

Shinn, E.A., 1968, Burrowing in recent lime sediments of 

Florida and the Bahamas: Journal of Paleontology, v. 42, p. 

879-894.

Shinn, E.A., 1968, Burrowing in recent lime sediments of 

Florida and the Bahamas: Journal of Paleontology, v. 42, p. 

879-884. 

Shoemaker, W.B., Cunningham, K.J., Kuniansky, E.L., and 

Dixon, J., 2008, Effects of turbulence on hydraulic heads 

and parameter sensitivities in preferential groundwater 

flow layers: Water Resources Research, v. 44, W03501, 

doi:10.1029/2007WR006601.

Sukop, M.C., Anwar, S., Lee, J.S., Cunningham, K.J., and 

Langevin, C.D., 2008, Modeling ground-water flow and 

solute transport in karst with Lattice Boltzmann methods, 

in Kuniansky, E.L., ed., Proceedings of the U.S. Geological 

Survey Karst Interest Group Workshop, May 27-29, 2008, 

Bowling Green, Kentucky: U.S. Geological Survey Scientific 

Investigations Report 2008-5023, p. 77-86.

Sukop, M.C., and Thorne, D.T., Jr., 2006, Lattice Boltzmann 

modeling: An introduction for geoscientists and engineers: 

New York, Springer, 172 p.

Wacker, M.A., and Cunningham, K.J., 2008, Borehole geophysical logging program: Incorporating new and existing 

techniques in hydrologic studies: U.S. Geological Survey 

Fact Sheet 2008-3098, 4 p.

U.S. Army Corps of Engineers, 2010, CERP Project—L-31N 

(L-30) Seepage Management Pilot: Accessed July 23, 2010, 

at http://www.evergladesplan.org/pm/projects/proj_36_l31n_

seepage.aspx.

For further information on carbonate aquifer

characterization, contact:

Kevin J. Cunningham

U.S. Geological Survey

3110 SW 9th Avenue

Fort Lauderdale, FL 33315

E-mail: kcunning@usgs.gov

For further information on Lattice Boltzmann

methods and geostatistics, contact:

Michael C. Sukop

Department of Earth & Environment

Florida International University

Miami, FL 33199

E-mail: sukopm@fiu.edu

Prepared by the Ft. Lauderdale Publishing Service Center