Dr. Xavier Comas         

Dr. Xavier Comas

Department of Geosciences
E-mail: xcomas@fau.edu   

Phone: 954-2361569 
Office: SE-460 (Boca) & DW-330 (Davie)

Environmental Geophysics Lab 


Ph.D. Rutgers University, 2005
B.Sc., Universitat de Barcelona (Spain), 2000

Research Interests: 

Application of hydrogeophysical methods for the imaging and characterization of the critical zone, including ground-penetrating radar (GPR), terrain conductivity, electrical and magnetic methods, and shallow seismic.

Characterization of the electromagnetic, electrical and hydrological properties of organic sediments with emphasis in carbon cycling and biogenic gas dynamics in peat soils, from the tropics to the Arctic.

Imaging of sinkholes, dissolution structures and porosity distribution in karst environments.

Fracture characterization and landscape evolution in granitic bedrock 



GLY 6457 Environmental Geophysics
GLY 6934 Ground Penetrating Radar
GLY 6934 Wetlands Geosciences
GLY 4451 Solid Earth Geophysics
GLY 4700 Geomorphology
GLY 4400C Structural Geology


PEER-REVIEWED JOURNAL ARTICLES: (* indicates student advised)

Sirianni*, M., and Comas, X. 2020. Changes in physical properties of Everglades peat soils induced by increased salinity at the laboratory scale: implications for changes in biogenic gas dynamics", Water Resources Research , 56, e2019WR026144. https://doi.org/10.1029/2019WR026144.

Chen, X., Comas, X., Reeve, A., and Slater, L. 2020. Evidence for glacial geological controls on the hydrology of Maine peatlands. Geology , https://doi.org/10.1130/G46844.1

Silvestri, S., Knight, R. J., Viezzoli, A., Richardson, C. J., Anshari, G. Z., Dewar, N. Flanagan, N. E., Comas, X. 2019. Quantification of peat thickness and stored carbon at the landscape scale in tropical peatlands: A comparison of airborne geophysics and an empirical topographic method. Journal of Geophysical Research: Earth Surface, 124 ; 2019JF005273

Gutiérrez, F., Carbonel, D., Sevil, J., Moreno, D., Linares, R., Comas, X., Zarroca, M., Roqué, C., McCalpin, J. P. 2019. Neotectonics and late Holocene paleoseismic evidence in the Plio-Quaternary Daroca Half-graben, Iberian Chain, NE Spain. Implications for fault source characterization, Journal of Structural Geology ,103933, doi: 10.1016/j.jsg.2019.103933.

Fabregat,, I., Gutiérrez, F., Roqué, C., Zarroca, M., Linares, R., Comas, X., Guerrero, J., Carbonel, D. 2019. Subsidence mechanisms and sedimentation in alluvial sinkholes inferred from trenching and ground penetrating radar (GPR). Implications for subsidence and flooding hazard assessment, Quaternary International , 525, 1-15, doi: 10.1016/j.quaint.2019.09.008

Comas, X .; Wright, W.; Hynek, S.; Fletcher, R.; and Brantley, S. 2018. Understanding fracture distribution and its relation to knickpoint evolution in the Rio Icacos watershed (Luquillo Critical Zone Observatory, Puerto Rico) using landscape‐scale hydrogeophysics,  Earth Surface Processes, and Landforms, doi: 10.1002/esp.4540.

Seo*, Seokju; Perez, Gabriela; Tewari, Ketan; Comas, Xavier; Kim, Myeongsub. 2018. Catalytic activity of nickel nanoparticles stabilized by adsorbing polymers for enhanced carbon sequestration. Nature-Scientific Reports ; volume 8 (1), 11786.

Chen, X.; Comas, X.; Binley, A.; and Slater, L. 2018. A lumped bubble capacitance model controlled by matrix structure to describe layered biogenic gas bubble storage in shallow subtropical peat. Water Resources Research . 54 (8), 5487-5503.

Wright*, W., Ramirez, J., and Comas, X. 2018. Methane ebullition from subtropical peat: testing an ebullition model reveals the importance of pore structure. Geophysical Research Letters , 45 (14), 6992-6999, doi:10.1029/2018GL077352.

Gutiérrez, F., Zarroca, M., Linares, R., Roqué, C., Carbonel D., Guerrero, J., McCalpin, J., Comas, X., Cooper, A. 2018. Identifying the boundaries of sinkholes and subsidence areas via trenching and establishing setback distances. Engineering Geology,223: 255-268; doi:10.1016/j.enggeo.2017.12.015

McClellan*, M., Comas, X., Benscoter, B., Hinkle, R., Sumner, D. 2017. Estimating belowground carbon stocks in isolated wetlands of the Northern Everglades Watershed, central Florida using ground penetrating radar (GPR) and aerial imagery. Journal of Geophysical Research-Biogeosciences. 122 (11), 2804-2816, doi: 10.1002/2016JG003573.

Mustasaar*, M. and Comas, X. 2017. Spatiotemporal variability in biogenic gas dynamics and composition in a subtropical peat soil at the laboratory scale is revealed using ground penetrating radar and gas traps. Journal of Geophysical Research-Biogeosciences, 122, doi: 10.1002/2016JG003714.

Comas, X.; Terry, N.; Hribljan, J.; Lilleskov, E. A.; Suarez, E.; Chimner, R. A.; and Kolka, R. K. 2017. Estimating belowground carbon stocks in peatlands of the Ecuadorian páramo using ground penetrating radar (GPR). Journal of Geophysical Research-Biogeosciences , 122, doi:10.1002/2016JG003550.

Fabregat, I., Gutierrez, F., Roqué, C., Comas, X., Zarroca, M., Carbonel Portero, D., Guerrero, J., and Linares, R. 2017. Reconstructing the internal structure and long-term evolution of hazardous sinkholes combining trenching, electrical resistivity imaging (ERI) and ground penetrating radar (GPR). Geomorphology , 285, 287–304.

Zarroca, M., Comas, X., Gutiérrez, F., Carbonel, D., Linares, R., Roqué, C., Morteza Mozafari, M., Mir, X., Guerrero, J. 2016. The application of GPR and ERI in combination with exposure logging and retrodeformation analysis to characterize sinkholes and reconstruct their impact on fluvial sedimentation. Gállego Valley, NE Spain. Earth Surface Processes and Landforms , doi: 10.1002/esp.4069.

Wright*, W., and X. Comas. 2016. Estimating methane gas production in peat soils of the Florida Everglades using hydrogeophysical methods, Journal of Geophysical Research Biogeosciences, 121(4), 2015JG003246.

Orlando, J., X. Comas, S. A. Hynek, H. L. Buss, and S. L. Brantley, 2016. The architecture of the deep critical zone in the Río Icacos watershed (Luquillo Critical Zone Observatory, Puerto Rico) inferred from drilling and ground penetrating radar (GPR), Earth Surface Processes and Landforms. 41(13), 1826-1840, doi: 10.1002/esp.3948.

Terry*, N., L. Slater, X. Comas, A. S. Reeve, K. V. R. Schäfer, and Z. Yu, 2016. Free-phase gas processes in a northern peatland inferred from autonomous field-scale resistivity imaging, Water Resources Research. , 52, 2996–3018, doi:10.1002/2015WR018111.

Pellicer, M., X., Corella, J. P., Gutiérrez, F., Roqué, C., Linares, R., Carbonel, D., Zarroca, M., Guerrero, J., Comas, X. 2016. Sedimentological and paleohydrological characterization of Late Pleistocene and Holocene tufa mound paleolakes using trenching methods in the Spanish Pyrenees. Sedimentology . 63: 1786-1819. doi: 10.1111/sed.12290.

Mount*, G., Comas, X., Wright*, W. and McClellan*, M. 2015. Delineation of macroporous zones in the unsaturated portion of the Miami Limestone using ground penetrating radar, Miami Dade County, Florida. Journal of Hydrology , 527, 872-883.

Comas X., Terry N., Slater L., Warren M., Kolka R., Kristijono A., Sudiana N., Nurjaman D., Taryono Darusman.2015.Imaging tropical peatlands in Indonesia using ground penetrating radar (GPR) and electrical resistivity imaging (ERI): implications for carbon stock estimates and peat soil characterization. Biogeosciences , 12, 2995-3007, doi: 10.5194/bg-12-2995-2015

Mount*, G. and Comas, X. 2014. Estimating porosity and solid dielectric permittivity in the Miami Limestone using high-frequency ground penetrating radar measurements at the laboratory scale. Water Resources Researc h, 50 (10), 7590-7605, doi: 10.1002/2013WR014947.

Comas, X. and Wright*, W. 2014. Investigating carbon flux variability in subtropical peat soils of the Everglades using hydrogeophysical methods. Journal of Geophysical Research-Biogeosciences , 119, doi:10.1002/2013JG002601.

Mount*, G., Comas, X., and Cunningham, K. 2014. Characterization of the porosity distribution in the upper part of the karst Biscayne aquifer using common offset ground penetrating radar, Everglades National Park, Florida. Journal of Hydrology , 515: 223-236.

Yeboah-Forson*, A, Comas, X., and Whitman, D.2014. Integration of electrical resistivity imaging and ground penetrating radar to investigate solution features in the Biscayne Aquifer. Journal of Hydrology . 515: 129-138.

Pellicer, X., Linares, R., Gutiérrez, F., Comas, X., Roqué, C., Carbonel, D., Zarroca, M., and Rodríguez, A. 2014. Morpho-stratigraphic characterization of a tufa mound complex in the Spanish Pyrenees using ground penetrating radar and trenching, implications for studies in Mars. Earth and Planetary Science Letters, 388: 197-210.

Bon, C. E., Reeve, A. S., Slater, L., and Comas, X. 2014. Using hydrologic measurements to investigate free phase gas ebullition in a Maine Peatland, USA, Hydrol. Earth Syst. S ci ., 18, 953-965, doi:10.5194/hess-10-953-2014.

Comas, X., Kettridge, N., Binley, A., Slater, L., Parsekian, A., Baird, A. J., Strack, M., and Waddington, J. M. 2013. The effect of peat structure on the spatial distribution of biogenic gases within bogs. Hydrological Processes , 28 (22), 5483-5494, doi: 10.1002/hyp.1005

Kettridge, N., Binley, A., Comas X., Cassidy, N., Baird, A., Harris, A., van der Kruk, J., Strack, M., Milner, A., Waddington, J. M. 2012. Do peatland microforms move through time? Examining the developmental history of a patterned peatland using ground penetrating radar. Journal of Geophysical Research-Biogeosciences , 117, G03030, doi:10.1029/2011JG001876.

Comas, X. and Wright*, W. 2012. Heterogeneity of biogenic gas ebullition in subtropical peat soils is revealed using time-lapse cameras, Water Resources Research , 48, W04601, doi:10.1029/2011WR011654.

Comas, X., Slater, L., and Reeve, A. 2011. Atmospheric Pressure Drives Changes in the Vertical Distribution of Biogenic Free-Phase Gasses in a Northern Peatland. Journal of Geophysical Research-Biogeosciences, 116, G04014, doi:10.1029/2011JG001701.

Parsekian*, A., Comas, X., Slater, L., and Glaser, P. 2011. Geophysical evidence for the lateral distribution of free-phase gas at the peat basin scale in a large northern peatland. Journal of Geophysical Research-Biogeosciences , 116, G03008, doi:10.1029/2010JG001543.

Comas, X., Slater, L., and Reeve, A. 2011. Pool patterning in a northern peatland: geophysical evidence for the role of postglacial landforms. Journal of Hydrology, 399 (3-4): 173-184.

Parsekian*, A., Slater, L., Comas, X. and Glaser, P., 2010. Variations in free‐phase gases in peat landforms determined by ground‐penetrating radar, Journal of Geophysical Research -Biogeosciences, 115, G02002, doi:10.1029/2009JG001086.

Kettridge, N., Comas, X., Baird, A., Slater, L., Strack, M., Thompson, D., Jol, H., and Binley A. 2008. Ecohydrologically-important subsurface structures in peatlands are revealed by Ground-Penetrating Radar and resistivity measurements. Journal of Geophysical Research-Biogeosciences , 113, G04030, doi:10.1029/2008JG000787.

Comas, X., Slater L., and Reeve A. 2008. Seasonal geophysical monitoring of biogenic gases in a northern peatland: Implications for temporal and spatial variability in free phase gas production rates, Journal of Geophysical Research-Biogeosciences, 113, G01012, doi:10.1029/2007JG000575.

Slater, L., Comas, X., Ntarlagiannis, D. and Roy Moulik, M., 2007. Resistivity-based monitoring of biogenic gasses in peat soils. Water Resources Research , 43, W10430, doi:10.1029/2007WR006090.

Comas, X. and Slater, L. 2007. Evolution of biogenic gasses in peat blocks inferred from non-invasive dielectric permittivity measurements. Water Resources Research , 43, W05424, doi: 10.1029/2006WR005562

Comas, X., Slater, L., and Reeve, A., 2007. In situ monitoring of ebullition from a peatland using ground penetrating radar (GPR). Geophysical Research Letters , 34 (6), L06402, doi: 10.1029/2006GL029014.

Comas, X., Slater, L and Reeve, A., 2005. Geophysical and hydrological evaluation of two bog complexes in a Northern Peatland: Implications for the distribution of biogenic gasses at the basin scale. Global Biogeochemical Cycles , 19, GB4023, doi: 10.1029/2005GB002582.

Comas, X., Slater, L. and Reeve, A., 2005. Stratigraphic controls on pool formation in a domed bog inferred from ground penetrating radar (GPR). Journal of Hydrology , 315 (1-4), 40-51.

Comas, X., Slater, L and Reeve, A., 2005. Spatial variability in biogenic gas accumulations in peat soils is revealed by ground penetrating radar (GPR). Geophysical Research Letters , 32 (8), L08401, doi: 10.1029/2004GL022297.

Comas, X. and Slater, L., 2004. Low-frequency electrical properties of peat. Water Resources Research , 40 (12), W12414, doi: 10.1029/2004WR003534.

Comas, X., Slater, L. and Reeve, A., 2004. Geophysical evidence for peat basin morphology and stratigraphic controls on vegetation observed in a northern peatland. Journal of Hydrology , 295, 173-184.



Baird, A., Belyea, L., Comas, X., Reeve, A. and Slater, L., 2009, Carbon Cycling in Northern Peatlands, Geophysical Monograph 184, American Geophysical Union (AGU), Washington DC, 299 pp



Comas, X. 2016. Peat, in Encyclopedia of Estuaries, edited by M. J. Kennish, pp. 476-480, Springer Netherlands, Dordrecht.

Comas, X. and Slater, L, 2009, Non-Invasive Field-Scale Characterization of Gaseous-Phase Methane Dynamics in Peatlands Using the Ground Penetrating Radar (GPR) Method: In, Baird, A., Belyea, L., Comas, X., Reeve, A. and Slater, L., Eds, Carbon Cycling in Northern Peatlands, Geophysical Monograph 184, American Geophysical Union (AGU), 159-172.

Reeve, A, Comas, X. and Slater, L., 2009, The influence of permeable mineral lenses on peatland hydrology In, Baird, A., Belyea, L., Comas, X., Reeve, A. and Slater, L., Eds, Carbon Cycling in Northern Peatlands, , Geophysical Monograph 184, American Geophysical Union (AGU), 289-298.

Baird, A., Comas, X., Slater, L. Belyea, L. and Reeve, A.S., 2009, Understanding Carbon Cycling in Northern Peatlands: Recent Developments and Future Prospects, In, Baird, A., Belyea, L., Comas, X., Reeve, A. and Slater, L., Eds, Carbon Cycling in Northern Peatlands, Geophysical Monograph 184, American Geophysical Union (AGU), p 1-4.

Slater L., and Comas, X., 2009. The contribution of GPR to water resources research. Chapter 7 of Ground Penetrating Radar: Theory and Applications, Edited by H. Jol, Elsevier, 544 pp.



Slater, L., Comas, X., Reeve, A., and Jol, H. 2007. Surveying Hydrology, Ecology, and Climate Effects of Northern Peatlands. Eos Trans. AGU, Vol. 88, No 42, p. 428.




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