Professor Emeritus. My research is focused on better understanding the flow of geofluids in the subsurface. I am interested in groundwater flow and the facilitated transport of solutes, particulates and heat within heterogeneous aquifer systems. I am also interested in the sequestration of CO_{2} within geologic reservoirs, and in the past influence of El Niño events on local watershed hydrology.

## Education History

- Ph.D. in Hydrology and Water Resources from the University of Arizona, 1989
- MS in Geological Sciences from Wright State University, 1983
- BA in Geology from Wittenberg University, 1981

## Research Statement

See publications listed below.

Funded Projects (NSF, DOE) have included:

Hydrogeology

- Understanding and modeling multi-scaled and hierarchical aquifer architecture
- Clarifying relationships between porosity, permeability and grain-size distributions
- Relating plume dispersion and retardation to sedimentary architecture within heterogeneous aquifer systems

Ecohydrology

- Quantifying and modeling processes associated with groundwater and surface water exchange of heat and nutrients in streambed sediments
- The influence of El Niño Southern Oscillation events on local hydrology

Energy

- Quantifying and understanding capillary trapping of CO
_{2}(secondary seal effect) injected for deep geologic sequestration

## Students Advised

#### Student Theses and Dissertations

(MS thesis unless otherwise indicated. Please also see the publication list below with references for the associated scientific articles published by these students)

- Blue, J., 2022, “Has winter weather in southwest Ohio been affected by the El Nino Southern Oscillation, the North Atlantic Oscillation, the Pacific Decadal Oscillation, and the Atlantic Multidecadal Oscillation?”
- Cornett, T., 2021, “Grain-size and permeability of sediments within the hyporheic zone at the Theis Environmental Monitoring and Modeling Site, Great Miami River and Buried Valley Aquifer, Southwest Ohio, USA”
- Delaney, N., 2020, “Quantifying contributions to the variance of permeability and porosity within the western-belt sandstones of the Cypress Formation, Illinois Basin”
- Shelters, A., 2019, “Paradoxical behavior in groundwater levels in response to precipitation events”
- Ghose, R., 2017, "Linking the local vertical variability of permeability and porosity to newly interpreted lithofacies at the site of the Illinois Basin -Decatur Project, Decatur, Illinois"
- Soltanian, R., 2015, Ph.D. Dissertation
**:**“Relating reactive transport to hierarchical and multiscale sedimentary architecture” - Young, N., 2014, “Effect of rivers on groundwater temperature in heterogeneous buried-valley aquifers: extent, attenuation, and phase lag of seasonal variation"
- Grigsby, N., 2012, “Evaluating the effect of hyporheic exchange on intake temperatures of open-loop geothermal wells in glacigenic outwash aquifers”
- Zhou, Y., 2012, “The influence of streambed heterogeneity on hyporheic exchange in gravelly rivers”
- Verdibello, S., 2012, “Evaluating the Kozeny-Carman model for permeability in binary grain mixtures”
- Porter, L., 2011, “The Kozeny-Carman equation considered with a percolation threshold”
- Huang, L, 2010, “Transport through georeservoirs: spatial entropy in hydraulic properties, and temporal entropy in residence time distributions”
- Mastera, L., 2010, “Estimating permeability from the grain-size distributions of natural sediment”
- Ramanathan, R., 2009,
- Guin, A., 2009, Ph.D. Dissertation: “The continuity of high-permeability zones in sedimentary deposits”
- Esselburn, J.D., 2009, “Porosity and permeability in ternary sediment mixtures”
- Ferreira, J.T., 2009, “Measuring the permeability of open-framework gravel”
- Damico, J., 2007, “Geostatistical Characterization of Heterogeneity in the Aberjona River Aquifer, Woburn, Massachusetts”
- Conrad, C., 2006, “Air-Based Measurements of Permeability in Pebbly Sands”
- Guin, A., 2005, “Linking Indicator Geostatistics to Percolation Theory in the Analysis of Spatial Continuity of Permeable Sediments”
- Popken, E., 2005, “Spatial Correlation of Permeability at the Oyster Site, Virginia”
- Kamann, P., 2004, “Porosity and Permeability in Sediment Mixtures”
- Roy, Motusi, 2004, “The Spatial Distribution of Permeability in Depositional Sedimentary Structures”
- Proce, C.J., 2002, “Multi-Scale Heterogeneity of the Spiritwood Buried-Valley Aquifer Region Modeled Using Transition Probability Geostatistics”
- Patterson, W.E., 2002, “Characterization of Heterogeneity in the Confluence of the Mackinaw and Mahomet Bedrock Valleys, Illinois, and Implications for Interconnectedness of Sand and Gravel Lithofacies”
- Reed, D. 2001, “Characterization of Heterogeneity Using Indicator Geostatistics in the Mahomet Sand Aquifer, Champaign County, Illinois”
- Bogle, J.L, 2000, “Characterization of Macrodispersion As Related to Facies Proportions and Orientation in Buried-Valley Aquifers”
- Kausch, K.W., 1999, “Analysis of Heterogeneity in a Northern Reach of the Miami Valley Aquifer Using Indicator Geostatistics”
- Means, B., 1999, “Evaluating Three Aspects of Methods Used to Characterize Transport in Buried-Valley Aquifers: Number of Particles Simulated, Flow Domain Length, and Variogram Range”
- Klohe, C.A., 1998, “Determining the Effects of Heterogeneity on Macrodispersion in Buried-Valley Aquifers with Dipping Facies Assemblages”
- Masters, R.W., 1998, “Geostatistical Simulations of Binary Heterogeneity and Characterizations of Transport From a Point Source in Buried Valley Aquifers”
- Gillett, B.E., 1997, “Geostatistical Characterization of the Mahomet Sand, Champaign County, Illinois”
- Greer, C.B., 1997, “A Three-Dimensional Geostatistical Model for the White River Aquifer System, Marion County, Indiana”
- Slesers, A.J., 1997, “A Geostatistical Analysis of the White River Aquifer System Underlying Indianapolis and Marion County, Indiana”
- Titzel, C.S., 1997, “Quantification of the Permeability Distribution Within Sand and Gravel Lithofacies in a Southern Portion of the Miami Valley Aquifer System”
- Bukowski, J.M., 1996, “Modeling the Fresh Water - Salt Water Interface in the Pleistocene Aquifer on Andros Island, Bahamas”
- Henderson, R.F., 1996, “Relation Between Soil Moisture, Vegetation, and Climate in a S.W. Ohio Wetland During 1993 and 1994”
- Henn, K.W., 1996, “Evaluation of Pumping Strategies for Capturing Aqueous Tetrachloroethylene and Trichloroethylene at Wright-Patterson Air Force Base, Ohio”
- Kreswick, K., 1996, “The Hydrogeological and Hydrogeochemical Characterization of Sandy Hook, a Prograding Carbonate Sand Body, San Salvador, Bahamas”
- Podgorney, R.K., 1996, “Capture Zone Geometry of a Fractured, Carbonate Aquifer”
- Basial, M.J., 1995, “The Worth of Geostatistical Information in Conditional Simulation and Transport Simulation: An Evaluation of Aquitard Continuity in Glaciofluvial, Buried-Valley Aquifers”
- Brown, N.R., 1995, “An Evaluation of Three-Dimensional Aquitard Continuity Within A Southern Reach of the Miami Valley Aquifer, Southwestern Ohio: A Geostatistical Analysis”
- McAlleney, P.J., 1995, “Using Geostatistics to Evaluate the Three-Dimensional Hydrofacies Geometry within a Portion of the Miami Valley Aquifer Near Moraine, Ohio”
- Martin, J.T., 1995, “The Correlation Between Solid-Phase Radium and Dissolved Radon In a Fractured Carbonate Aquifer In Southwestern Ohio”
- Chapman, Mike, 1994, “A Study of the Ground Water Temperature Gradients Within a Constructed Wetland and Effects on the Establishment and Distribution of Vegetation.”
- Goel, Shubhra, 1994, “Understanding Ground Water Flow Through a Constructed Fen in the Beavercreek Wetlands,Ohio”
- McCready, Roger, 2004, “A Boron Plume Migration and Hydrogeological Interpretation Study Using Groundwater Flow and Solute Transport Modeling”
- Shestak, Carol, 2004, “Spatial Variability in the Hydrogeochemistry of a Near Surface Aquifer, and Spurious Factors Due to Temporal Variability”
- Zahradnik, Arthur, 2004, “Quantifying the Uncertainty Associated with Preferential Flow Paths for Flow and Transport Modeling in Glaciofluvial Buried Valley Aquifer Settings”
- Gall, Ivan, 2003, “The Correlation Between Bedrock Uranium and Dissolved Radon in Ground Water of a Fractured Carbonate Aquifer in Southwestern Ohio”
- Strecker, John, 2003, “Determination of Volumetric Soil Moisture Content Variations and the Relation to Vegetative Biomass in a Constructed Fen, Southwestern Ohio”
- Aguirre, Aida, 2002, “Finite Element Modeling of Seepage Pressures Within an Earthen Dam Under the Maximum Probable Flood”
- Russo, Luigi, 2002, “Evaluation of the Efficiency of Pressure Relief Wells”
- Balmer, Richard, 1991, “Evaluation of a Proposed Modification of the Slope Matching (SM) Method of Aquifer Test Analysis for the Determination of Transmissivity and Storativity”
- Field, Adrian, 1991, “Application of a Three Dimensional Ground Water Flow Model and Particle Tracking for Well Field Management”
- Smith, Ronald, 1991, “Use of Multilevel Slug Testing and Mass Transport Modeling to Evaluate Impacts of Heterogeneity on Nitrate Transport in Fractured Carbonate Rocks”
- Wright, Stephen, 1991, “Statistical Analysis of Spatial Variations in Regional Hydrogeochemistry Utilizing Factor Analysis and Correspondence Analysis”
- Andolsek, Robert, 1990, “Advective Mass Transport in an Anisotropic, Fractured, Carbonate Aquifer”
- Basile, Joseph, 1989, “A Dual Approach to Evaluating the Ground Water Pollution Potential to an Aquifer System in Cortland County, New York, Using Both the "DRASTIC" Methodology and the Estimation of Advective Fluid Velocities”

## Publications

**Peer-Reviewed Publications** (Many are available at Dr. Ritzi's CORE Scholar Site)

* denotes current or former students or post-docs and WSU researchers

† denotes invited submissions

- R. Ritzi, Roberson, L., and M. Bottomley, (2021), El Niño Southern Oscillation (1896 to 2016): Quantifying Effects on Winter Precipitation and Temperature in Southwest Ohio, USA,
*Ohio Journal of Science*, 121(2): 64-77, https://doi.org/10.18061/ojs.v121i2.7650 - Zhang, X, F Ma, S. Yin, C. Wallace, M. Soltanian, Z. Dai, Z. Ma, C. Zhan, and R. Ritzi, (2021), “Application of upscaling methods for fluid flow and mass transport in multi-scale heterogeneous media: A critical review,”
*Applied Energy*, (303), https://doi.org/10.1016/j.apenergy.2021.117603 - Ershadnia, R., S. Hajirezaie; A. Amooie; C. Wallace; N. Gershenzon; S. Hosseini; D. Sturmer; R. Ritzi; and R. Soltanian, (2021), “CO
_{2}Geological Sequestration in Multiscale Heterogeneous Aquifers: Effects of Heterogeneity, Connectivity, Impurity, and Hysteresis,”*Advances in Water Resources*, (151), https://doi.org/10.1016/j.advwatres.2021.103895 - Reesink, R., J. Best, C. Monson, J. Freiberg, and R. Ritzi, (2020), Interpreting pre-vegetation landscape dynamics: the Cambrian Lower Mount Simon Sandstone, Illinois, USA,
*Journal of Sedimentary Research*, (90), doi: 10.2110/jsr.202.7 - Dai*, Z., C. Zhan, M. R. Soltanian*, R. Ritzi, (2019), Identifying spatial correlation structure of multimodal permeability in hierarchical media with Markov Chain approach,
*Journal of Hydrology*, v.568 p. 703-715, 10.1016/j.jhydrol.2018.11.032 - Damico*, J.R., R.W. Ritzi, N.I. Gershenzon*, and R.T. Okwen, (2018),, Challenging geostatistical methods to represent heterogeneity in CO2 reservoirs: evaluation in the context of residual trapping of CO2,
*Environmental and Engineering Geoscience*, 24 (4), 357-373, 10.2113/EEG-2116, Best Publication Award given in 2019 by the Association of Engineering Geologists - Ritzi, R.W., R. Ghose*, M. Bottomley, A.J.H. Reesink, J. Best, J.T. Freiburg and N.D. Webb, (2018), Linking the local vertical variability of permeability and porosity to newly-interpreted lithofacies in the lower Mt. Simon CO
_{2}reservoir,*International Journal of Greenhouse Gas Control*, 68, p. 26–41, http://dx.doi.org/10.1016/j.ijggc.2017.09.017 - Soltanian, M.R., M. Amooie, N.I. Gershenzon*, Z. Dai, F. Xiong, R.W. Ritzi, D. Cole, J. Moortgat, (2017), “Dissolution trapping of carbon dioxide in heterogeneous aquifers,”
*Environmental Science and Technology**,*51 (13), pp 7732–7741, DOI: 10.1021/acs.est.7b01540 - †Gershenzon*, N.I, R.W. Ritzi, D. Dominic, E. Mehnert, and R. Okwen, (2017) “Effective constitutive relations for simulating CO
_{2}capillary trapping in heterogeneous reservoirs with fluvial sedimentary architecture”, special issue of*Geomechanics and Geophysics for Geo-Energy and Geo-Resources*titled*: Geologic CO*. 3(3), pp 221–223, DOI 10.1007/s40948-017-0057-3_{2}Sequestration - Gershenzon*, N.I, R.W. Ritzi, D. Dominic, E. Mehnert, and R. Okwen, (2017) “Capillary trapping of CO
_{2}in heterogeneous reservoirs during the injection period”,*International Journal of Greenhouse Gas Control*(59), p. 13-23. http://dx.doi.org/10.1016/j.ijggc.2017.02.002 - Freiburg, J., R. Ritzi and K. Kehoe, (2016), Depositional and diagenetic controls on porosity within a deeply buried CO
_{2}storage reservoir—the Cambrian Mt. Simon Sandstone, Illinois Basin, USA, submitted to*International Journal of Greenhouse Gas Control*, 55 (2016) 42–54, http://dx.doi.org/10.1016/j.ijggc.2016.11.005 - Gershenzon*, N.I, R.W. Ritzi, D. Dominic, E. Mehnert, R. Okwen, and C. Patterson, (2016), CO
_{2}trapping in reservoirs with fluvial architecture: sensitivity to heterogeneity in permeability and constitutive relationship parameters for different rock types,*Journal of Petroleum Science and Engineering*, http://dx.doi.org/10.1016/j.petrol.2016.09.008 - Gershenzon*, N.I, R.W. Ritzi, D. Dominic, E. Mehnert, and R. Okwen, (2016) “Comparison of CO
_{2}Trapping in Heterogeneous Reservoirs with Brooks-Corey and van Genuchten Capillary Pressure Curves”,*Advances in Water Resources*, 96, 225-236, http://dx.doi.org/10.1016/j.advwatres.2016.07.022 - Ritzi, R.W., J.T. Freiburg, N.D. Webb, (2016), “Understanding the (co)variance in petrophysical properties of CO
_{2}reservoirs comprising fluvial sedimentary architecture,”*International Journal of Greenhouse Gas Control*, 51, p. 423–434, http://dx.doi.org/10.1016/j.ijggc.2016.05.001 - Gershenzon*, N.I, M. R. Soltanian*, R.W. Ritzi, D. Dominic, E. Mehnert, and R. Okwen, (2015) “Influence of small-scale, fluvial, sedimentary architecture on CO
_{2}trapping processes in deep saliner”,*Water Resources Research*, 51, 8240–8256, doi: 10.1002/2015WR017638 - Gershenzon*, N.I, M. R. Soltanian*, R.W. Ritzi, D. Dominic, D. Keefer, E. Shaffer, B. Storsved ”(2015) How does the connectivity of open-framework conglomerates within multi-scale hierarchical fluvial architecture affect oil sweep efficiency in waterflooding? ”
*Geosphere*, v. 11, no. 6, p. 2049–2066, doi:10.1130/GES01115.1 - †Ritzi, R.W., and R.M. Soltanian*, (2015), What have we learned from deterministic geostatistics at highly resolved field sites, as relevant to mass transport processes in sedimentary aquifers?,
*Journal of Hydrology*, doi:10.1016/j.jhydrol.2015.07.049 - Soltanian*, M.R., R.W. Ritzi, C. Huang, Z. Dai, H. Deng " (2015) A note on upscaling retardation factor in hierarchical porous media with multimodal reactive mineral facies",
*Transport in Porous Media,*doi:10.1007/s11242-015-0480-2 - Soltanian*, M.R., R.W. Ritzi, C. Huang, Z. Dai (2015) “Relating reactive solute transport to hierarchical and multiscale sedimentary architecture in a Lagrangian-based transport model: 1. Time-dependent retardation factor ,"
*Water Resources Research*, 51, doi:10.1002/2014WR016353. - Soltanian*, M.R., R.W. Ritzi, C. Huang, Z. Dai " (2015) Relating reactive solute transport to hierarchical and multiscale sedimentary architecture in a Lagrangian-based transport model: 2. Particle displacement variance,"
*Water Resources Research*, 51, doi:10.1002/2014WR016354. - Soltanian*, M.R., R.W. Ritzi, C. Huang, Z. Dai (2015) “Reactive Solute Dispersion in physically and chemically heterogeneous porous media with multimodal reactive mineral facies: The Lagrangian approach,"
*Chemosphere*, V 122, p. 235-244, doi:10.1016/j.chemosphere.2014.11.064 - Soltanian*, M.R., R.W. Ritzi (2014) “A new method for analysis of variance of the hydraulic and reactive attributes of aquifers as linked to hierarchical and multi-scaled sedimentary architecture”,
*Water Resources Research*, doi:10.1002/2014WR015468. - Soltanian*, M.R., R.W. Ritzi, Z. Dai, C. Huang, D. Dominic (2014) "Transport of kinetically sorbing solutes in heterogeneous sediments with multimodal conductivity and hierarchical organization across scales",
*Stochastic Environmental Research and Risk Assessment*, doi: 10.1007/s00477-014-0922-3. - Gershenzon*, N.I, M. R. Soltanian*, R.W. Ritzi, D. Dominic (2014) “Influence of small scale heterogeneity on CO2 trapping processes in deep saline aquifers”,
*Energy Procedia*, V. 59, p. 166-173, doi: 10.1016/j.egypro.2014.10.363 - Gershenzon, N.I., Soltanian*, M. R., Ritzi, R.W., Dominic, D.F., (2014), Understanding the impact of open-framework conglomerates on water-oil displacements: Victor Interval of the Ivishak Reservoir, Prudhoe Bay Field, Alaska,
*Petroleum Geosciences*, doi:10.1144/petgeo2014-017 - Ritzi, R.W., L. Huang*, R. Ramanathan*, and R. M. Allen-King, 2013, Horizontal spatial correlation of hydraulic and reactive transport parameters as related to hierarchical sedimentary architecture at the Borden research site,
*Water Resources Research*, 49, 1–13, doi:10.1002/wrcr.20165 - Zhou, Y.Q.*, R.W. Ritzi, R. Soltanian*, and D.F. Dominic, 2013, The influence of streambed heterogeneity on hyporheic flow in gravelly rivers,
*Ground Water,*doi: 10.1111/gwat.12048 - Porter*, L.B., R.W. Ritzi, L.J. Mastera*, D.F. Dominic, B. Ghanbarian-Alavijeh*, 2012, The Kozeny-Carman equation with a percolation threshold,
*Ground Water*, DOI: 10.1111/j.1745-6584.2012.00930.x - Huang*, L., R.W. Ritzi, R. Ramanathan*, 2011, Conservative models: parametric entropy vs. temporal entropy in outcomes,
*Ground Water*, DOI: 10.1111/j.1745-6584.2011.00832.x - Esselburn*, J.D., R.W. Ritzi, and D.F. Dominic, 2010, Porosity and permeability in ternary sediment mixtures,
*Ground Water*, doi: 10.1111/j.1745-6584.2010.00744.x - Ferreira*, J.T., R.W. Ritzi, and D.F. Dominic, 2010, Measuring the permeability of open-framework gravel,
*Ground Water*, doi: 10.1111/j.1745-6584.2010.00675.x - Ramanathan*, R., A. Guin*, R.W. Ritzi, D.F. Dominic, V.L. Freedman, T.D. Scheibe, and I.A. Lunt, 2010, Simulating the heterogeneity in channel belt deposits: Part 1. A geometric-based methodology and code,
*Water Resources Research*, V. 46, doi:10.1029/2009WR008111 - Guin*, A., R. Ramanathan*, D.F. R.W. Ritzi, Dominic, I.A. Lunt, T.D. Scheibe, and V.L. Freedman, 2010, Simulating the heterogeneity in channel belt deposits: Part 2. Examples of results and comparison to natural deposits,
*Water Resources Research,*V. 46, doi:10.1029/2009WR008112 - Ramanathan*, R., R.W. Ritzi, and R.M. Allen-King, 2010, Linking hierarchical stratal architecture to plume spreading in a Lagrangian-based transport model: Part II. Evaluation using new data from the Borden site,
*Water Resources Research*, V. 46, W01510, doi:10.1029/2009WR007810 - Ritzi, R.W., and P. Bobeck, 2008, Comprehensive principles of quantitative hydrogeology established by Darcy (1856) and Dupuit (1857),
*Water Resources Research*, 44, W10402, doi:10.1029/2008WR007002 - Guin*, A., and R.W. Ritzi, 2008, “Studying the effect of correlation and finite-domain size on spatial continuity of permeable sediments,”
*Geophysical Research Letters*, V35, L10402, doi:10.1029/2007GL032717 - Ramanathan*, R., R. Ritzi, and C. Huang, 2008, “Linking hierarchical stratal architecture to plume spreading in a Lagrangian-based transport model,”
*Water Resources Research,*V44*,*W04503, doi:10.1029/2007WR006282 - Sun, A.Y., R.W. Ritzi, and D. Sims, 2008, “Characterization and modeling of spatial variability in a complex alluvial aquifer: Implications on solute transport,”
*Water Resources Research,*V44, W04402, doi:10.1029/2007WR006119 - Conrad*, C.M., R.W. Ritzi, and D.F. Dominic, 2008, “Air-based measurements of permeability in pebbly sands,”
*Ground Water*, 46(1), p. 103-112,, doi:10.1111/j.1745-6584.2007.00379.x - Dai*, Z., A. Wolfsberg, Z. Lu, and R. Ritzi, (2007), “Representing aquifer architecture in macrodispersivity models with an analytical solution of the facies transition probability matrix,”
*Geophysical Research Letters*, 34, L20406, doi:10.1029/2007GL031608 - Kamann*, P.J., R.W. Ritzi, D.F. Dominic, and C.M. Conrad*, 2007, “Porosity and permeability in sediment mixtures,”
*Ground Water*, doi: 10.1111/j.1745-6584.2007.00313.x - Ritzi, R.W., and R.M. Allen-King, 2007, “Why did Sudicky (1986) find an exponential-like spatial correlation structure for hydraulic conductivity at the Borden research site?”
*Water Resources Research*, 43, W01406doi: 10.1029/2006WR004935 - †Ritzi, R.W. and Z. Dai*, 2006, Introduction: Modeling groundwater flow and reactive transport in physically and chemically heterogeneous media,
*Geosphere*, 2(2), doi: 10.1130/GES0202INT.1 - †Dai*, Z., J. Samper, and R.W. Ritzi, 2006, Identifying geochemical processes by inverse modeling of multicomponent reactive transport in the Aquia aquifer,
*Geosphere*, 2(2), doi: 10.1130/GES00021.1 - Ritzi, R.W., and Z. Dai*, 2006,
*Guest**Editors*, Special Issue: Modeling groundwater flow and reactive transport in physically and chemically heterogeneous media,*Geosphere*, Volume 2(2), (eight papers). - Ritzi, R. W., Z. Dai*, D. F. Dominic, and Y. Rubin, 2006, Reply to comment by Shlomo P. Neuman on “Spatial correlation of permeability in cross-stratified sediment with hierarchical architecture,”
*Water Resources Research*, 42, W05602doi: 10.1029/2005WR004402 - Dai*, Z., R.W. Ritzi, and D.F. Dominic, 2005, “Improving permeability semivariograms with transition probability models of hierarchical sedimentary architecture derived from outcrop-analog studies,”
*Water Resources Research*, 41, W07032doi: 10.1029/2004WR002515 - Ritzi, R. W.; Dai*, Z.; Dominic, D. F.; Rubin, Y. N., 2004, “Spatial correlation of permeability in cross-stratified sediment with hierarchical architecture,”
*Water Resources Research*, 40(3), W03513doi: 10.1029/2003WR002420 - †Dai*, Z., Ritzi, R. W., C. Huang, Y. Rubin and D. F. Dominic, 2004, “Transport in heterogeneous sediments with multimodal conductivity and hierarchical organization across scales,”
*Journal of Hydrology*, v. 294, Issues 1-3, p. 68-86. - Proce*, C.J., R.W. Ritzi, D.F. Dominic, and Z. Dai*, 2004, “Modeling multiscale heterogeneity and aquifer interconnectivity,”
*Ground Water*, 42(5), p. 658-670. - †Dai*, Z., R.W. Ritzi, and D.F. Dominic, 2004, “Estimating parameters for hierarchical permeability correlation models,” in
*Aquifer Characterization*, Eds. J. Bridge and D Hyndman, SEPM Special Publication No. 80, SEPM Publishing, Tulsa, p. 41-54. - †Ritzi, R.W., Z. Dai*, D.F. Dominic, and Y.N. Rubin, 2003, “Review of permeability in buried-valley aquifers: centimeter to kilometer scales,” in
*Calibration and Reliability in Groundwater Modelling: A Few Steps Closer to Reality*, K. Kovar,*ed.*, IAHS Publ. no. 277. - Dai, Z., R.W. Ritzi, D.F. Dominic and Y.N. Rubin, 2003, “Estimating spatial correlation structure for permeability in sediments with hierarchical organization,
*in**Groundwater Quality Modeling and Management Under Uncertainty*,” S. Mishra,*Ed*., American Society of Civil Engineers, Philadelphia, p. 83-100. - †Ritzi, R.W., Z. Dai*, D.F. Dominic, and Y.N. Rubin, 2002, “Spatial structure of permeability in relation to hierarchical sedimentary architecture: centimeter to kilometer scales,” in
*Bridging the Gap between Measurement and Modeling in Heterogeneous Media*, A. Findikakis,*ed.*, IAHS and Lawrence Berkeley National Laboratory, CD ROM - Bukowski*, J.M, R.W. Ritzi, C. Carney, and M. Boardman, 2001, “Explaining the thinness of fresh water lenses in the Pleistocene carbonate aquifer on Andros Island, Bahamas,”
*Journal of Ground Water*, 39(5), p. 731-720. - Ritzi, R.W., 2000, “Behavior of indicator variograms and transition probabilities in relation to the variance in lengths of hydrofacies,”
*Water Resources Research*, 36(11), p. 3375-3381. - Ritzi, R.W., D.F. Dominic, A.J. Slesers*, C.B. Greer*, E.C. Reboulet*, J.A. Telford*, R.W. Masters*, C.A. Klohe*, J.L. Bogle*, and Brent P. Means*, 2000, “Comparing statistical models of physical heterogeneity in buried-valley aquifers,”
*Water Resources Research*, 36(11), p. 3179-3192. - †Dominic, D.F., R.W. Ritzi, E.C. Reboulet*, and A.C. Zimmer*, 1998, “Geostatistical analysis of facies distributions: elements of a quantitative facies model,” in
*Hydrogeologic Models of Sedimentary Aquifers, Concepts in Hydrogeology and Environmental Geology No. 1*, SEPM (Society of Sedimentary Geology) Publishers, p. 137-145. - Podgorney*, R.K., and R.W. Ritzi, 1997, “Capture zone geometry of a fractured, carbonate aquifer,”
*Journal of Ground Water.*35(6), p. 1040-1050. - †Ritzi, R.W., D.F. Dominic, and K. Kausch*, 1996, “Aquitard distribution in a northern reach of the Miami valley aquifer: 1) three-dimensional geostatistical evaluation of physical heterogeneity,”
*Hydrogeology Journal.*4(2), p. 12-24. - †Dominic, D.F., R.W. Ritzi, and K. Kausch*, 1996, “Aquitard distribution in a northern reach of the Miami valley aquifer: 2) three-dimensional analysis of facies,”
*Hydrogeology Journal.*4(2), p. 25-35. - Sminchak*, J.R., D.F. Dominic, and R.W. Ritzi, 1996, “Indicator geostatistical analysis of sand interconnections within a till,”
*Journal of Ground Water*, 36(5), p. 1125-1131. - Ritzi, R.W., D.F. Dominic, N.R. Brown*, K.W. Kausch*, P.J. McAlenney*, and M.J. Basial*, 1995, “Hydrofacies distribution and correlation in the Miami Valley aquifer system,”
*Water Resources Research*, 31(12), p. 3271-3281. - Gall*, I.K., R.W. Ritzi, A.D. Baldwin, P.D. Pushkar, C.K. Carney, and J.F. Talnagi, Jr., 1994, “The correlation between bedrock uranium and dissolved radon in ground water of a fractured carbonate aquifer in southwestern Ohio,”
*Journal of Ground Water*, 33(2), p. 197-206. - Ritzi, R.W., D.F. Jayne*, A.J. Zahradnik*, A.A. Field*, and G.E. Fogg, 1994, “Geostatistical modeling of heterogeneity in glaciofluvial, buried-valley aquifers,”
*Journal of Ground Water*, 32(4), p. 666-674. - Smith*, R.T, and R.W. Ritzi, 1993, “Designing a nitrate monitoring program in a heterogeneous, carbonate aquifer,”
*Journal of Ground Water*, 31(4), p. 576-585. - Ritzi, R.W., S.L. Wright*, B. Mann, and M. Cheng, 1993, “Considering the issue of temporal variability of regional hydrogeochemical data in a multivariate analysis of spatial variability,”
*Journal of Ground Water*, 31(2), p. 221-229. - Ritzi, R.W., and H.A. Andolsek*, 1992, “Relation between anisotropic transmissivity and azimuthal resistivity surveys in shallow, fractured, carbonate flow systems,”
*Journal of Ground Water*, 30(5), p. 774-780. - Ritzi, R.W., S. Sorooshian, and V.K. Gupta, 1991, “On the estimation of parameters for frequency domain models,”
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