Geological realism in hydrogeological and geophysical inverse modeling: a review

摘要

Scientific curiosity, exploration of georesources and environmental concernsare pushing the geoscientific research community toward subsurfaceinvestigations of ever-increasing complexity. This review explores variousapproaches to formulate and solve inverse problems in ways that effectivelyintegrate geological concepts with geophysical and hydrogeological data. Moderngeostatistical simulation algorithms can produce multiple subsurfacerealizations that are in agreement with conceptual geological models andstatistical rock physics can be used to map these realizations into physicalproperties that are sensed by the geophysical or hydrogeological data. Theinverse problem consists of finding one or an ensemble of such subsurfacerealizations that are in agreement with the data. The most general inversionframeworks are presently often computationally intractable when applied tolarge-scale problems and it is necessary to better understand the implicationsof simplifying (1) the conceptual geological model (e.g., using modelcompression); (2) the physical forward problem (e.g., using proxy models); and(3) the algorithm used to solve the inverse problem (e.g., Markov chain MonteCarlo or local optimization methods) to reach practical and robust solutionsgiven today's computer resources and knowledge. We also highlight the need tonot only use geophysical and hydrogeological data for parameter estimationpurposes, but also to use them to falsify or corroborate alternative geologicalscenarios.