Forward and Inverse Models Over 70 Years

Abstract

The transition over 70 years from qualitative rock description to attempted quantitative description of rocks and rock bodies (inverse modelling) and testing of process models with observation data (forward models) are outlined. Dramatic increases of readily measured variables, combined with almost unlimited computing power, yielded a plethora of varied inverse models, but limited attention has been given to critical sampling, variance, closure, 'black swan', and nonlinear issues; recent approaches to closure problems hold promise. Especially for plutonic rocks, paucity of quantitative process modelling left exciting forward-modelling opportunities neglected. Resulting challenges ahead are anticipated. Keywords Sampling ⋅ Variance ⋅ Composition variability ⋅ Black swans Granite composition 37.1 Birth of IAMG in 1968 In many different ways, 1968 was an extraordinary year that rocked the world (cf., Kurlansky 2004). Some 20 enthusiasts gathered at the XXIII International Geological Congress in Prague's New Technical University, Czechoslovakia, to create the International Association for Mathematical Geology in exciting, but tragic, times. Soviet troops had occupied the city a couple of days previously; guns of encircling Soviet tanks pointed at the university, which was the centre for printing and disseminating news. Vistelius was elected first IAMG President and Krumbein 'Past President' (a designation he appreciated and found amusing!); both are fathers of geological models.

Machine Learning for Bayesian Experimental Design in the Subsurface

“…These processes are typically described by pde systems solved numerically, which is known as forward modeling. Whitten (2018) reviews the history and challenges of forward modeling in geosciences, and Pham and Tsai (2017) and Singh (2018) review the subject in groundwater modeling.…”