John N. Hooker, Ph.D.

John N. Hooker, Ph.D.

Assistant Professor, Environmental Science Office Location: Bonilla Science Hall, Room 234A Phone: (210) 805-3099
Dr. Hooker grew up in Beaumont, Texas. He studied geology at UT Austin, where he earned his B.A., M.S., and Ph.D.. He minored in astronomy and loves learning about nature. He also enjoys reading about history and economics and reading a wide range of fiction. He was a postdoctoral scholar at the University of Oxford and an instructor at Penn State before arriving at UIW. His studies have taken him all over the world, including Bolivia, Scotland, Jordan, and many places in between. In his spare time, he likes to play chess and ultimate frisbee, sing Gilbert and Sullivan, practice piano and guitar, and travel with his wife, son, and daughter.
  • B.A., The University of Texas at Austin
  • M.S., The University of Texas at Austin
  • Ph.D., The University of Texas at Austin
  • Research Scientist Associate, Bureau of Economic Geology, Austin, Texas
  • Postdoctoral Research Associate, University of Oxford, Oxford, UK
  • Assistant Teaching Professor, Penn State University
  • Hooker, J.N., Marrett, R., and Wang, Q., 2023. Rigorizing the use of the coefficient of variation to diagnose fracture periodicity and clustering. Journal of Structural Geology 168, 104830, doi: 10.1016/j.jsg.2023.104830
  • Hooker, J.N., Cartwright, J., Stephenson, B., and Day, C.C., 2023. Continuous versus punctuated vein widening in the Marcellus Formation, USA: the fine line between pressure fringes and hydraulic fractures. Geological Magazine 159, 2020-2035, doi: 10.1017/S0016756822000371
  • Hooker, J.N. and Fisher, D.M., 2021. How cementation and fluid flow influence slip behavior at the subduction interface. Geology, doi: 10.1130/G48741.1
  • Hoyt, E.M. and Hooker, J.N., 2021. Silica diagenesis and natural fracturing in limestone: An example from the Ordovician of Central Pennsylvania. Marine & Petroleum Geology 132, 105240. doi: 10.1016/j.marpetgeo.2021.105240
  • Hooker, J.N., Ruhl, M., Dickson, A.J., Hansen, L.N., Idiz, E., Hesselbo, S.P., and Cartwright, J., 2020. Shale anisotropy and natural hydraulic fracture propagation: An example from the Jurassic (Toarcian) Posidonienschiefer, Germany. Journal of Geophysical Research—Solid Earth, doi: 10.1029/2019JB018442
  • Hooker, J.N., Abu-Mahfouz, I.S., Meng, Q., and Cartwright, J., 2018. Fractures in mudrocks: advances in constraining timing and understanding mechanisms. Journal of Structural Geology 125, 166-173. doi: 10.1016/j.jsg.2018.04.020
  • Hooker, J.N. and Cartwright, J., 2018. Dolomite overgrowths suggest a primary origin of cone-in cone. Geological Magazine 155 (3), 568-585. doi: 10.1017/S0016756816000807
  • Hooker, J.N., Laubach, S.E., and Marrett, R., 2018. Microfracture spacing distributions and the evolution of fracture patterns in sandstones. Journal of Structural Geology 108, 66-79. doi: 10.1016/j.jsg.2017.04.001
  • Hooker, J.N., Huggett, J.M., Cartwright, J., and Ali Hussein, M., 2017. Regional-scale development of opening-mode calcite veins due to silica diagenesis. Geochemistry, Geophysics, Geosystems, doi: 10.1002/2017GC006888
  • Hooker, J.N. and Katz, R.F., 2015. Vein spacing in extending, layered rock: the effect of synkinematic cementation. American Journal of Science 315, 557-588. doi: 10.2475/06.2015.03
  • Hooker, J.N., Larson, T.E., Eakin, A., Laubach, S.E., Eichhubl, P., Fall, A., and Marrett, R., 2015. Fracturing and fluid-flow in a subdécollement sandstone; or, a leak in the basement. Journal of the Geological Society 172, 428-442. doi:10.1144/jgs2014-1
  • ENSC 1410 Introduction to Environmental Science
  • ENSC 3410 Research in Soil Conservation
  • ENSC 4460 Research in Water Quality
  • GEOL 1401 Physical Geology
  • GEOL 1420 Oceanography
  • GEOL/METR 3340 Hydrology
  • GEOL 3450 Environmental Geology
Dr. Hooker's main research focus is about how chemical reactions influence fracturing in Earth's crust. Natural fractures host devastating earthquakes and provide the space for fluids to circulate through the crust. Natural fracture patterns, in space and time, are affected by mineral reactions, and understanding this interaction can improve our ability to predict when and where fracture opening or slip events will occur. Fracturing, in turn, enables mineral reactions by generating reactive surface areas in the crust. This process enables ore deposit formation as well as silicate weathering, by which silicon-bearing minerals dissolve and contribute alkalinity to surface waters, ultimately drawing down atmospheric carbon dioxide. Dr. Hooker's recent work has included developing an earthquake simulator (www.mefisto.org), experimenting with plant and fungus growth to break down olivine, building tools to distinguish nonrandom fracture patterns, and using cemented fractures to retrace paleofluid conditions in the subsurface. He is a research fellow with the Structural Diagenesis Initiative at UT Austin (www.jsg.utexas.edu/sdi/) and is always happy to talk rock.