3-D Structural geological models: Concepts, methods, and uncertainties

Abstract

The Earth below ground is the subject of interest for many geophysical as well as geological investigations. Even though most practitioners would agree that all available information should be used in such an investigation, it is common practice that only a fraction of geological and geophysical information is used. We believe that some reasons for this omission are (a) an incomplete picture of available geological modeling methods, and (b) the problem of the perceived static picture of an inflexible geological representation in an image or geological model. With this work, we aim to contribute to the problem of subsurface interface detection through (a) the review of state-of-the-art geological modeling methods that allow the consideration of multiple aspects of geological realism in the form of observations, information and knowledge, cast in geometric representations of subsurface structures, and (b) concepts and methods to analyze, quantify, and communicate related uncertainties in these models. We introduce a formulation for geological model representation and interpolation and uncertainty analysis methods with the aim to clarify similarities and differences in the diverse set of approaches that developed in recent years. We hope that this chapter provides an entry point to recent developments in geological modeling methods, helps researchers in the field to better consider uncertainties, and supports the integration of geological observations and knowledge in geophysical interpretation, modeling and inverse approaches.

Topological analysis in Monte Carlo simulation for uncertainty propagation

“…Note that in all three cases, these operations are further simplifications of the models and add more uncertainty to the final outcome. Each of these transformations allow for different comparative analyses to be run: (i) voxets are used to build probabilistic geological models and uncertainty index models such as entropy or stratigraphic variability (Wellmann and Regenauer-Lieb, 2012;Lindsay et al, 2012); (ii) the shape of triangulated surfaces may be used to estimate the variability of curvature (Lindsay et al, 2013). Furthermore, the results of these analyses can be fed to external validation systems to reduce geological uncertainty and improve understanding of the modeled volume.…”

Global Sensitivity Analysis to Optimize Basin-Scale Conductive Model Calibration – A Case Study From the Upper Rhine Graben

“…) and of the relevant parameters (hydraulic and thermal conductivities, radiogenic heat production, etc.). To compensate for these model errors, arising from, for instance, measurement errors, generalizations, and geometrical uncertainties (Houghton et al, 2001;Murphy et al, 2004;Refsgaard et al, 2007;Wellmann & Caumon, 2018), we need model calibrations to obtain reliable and robust models. Here, we investigate the requirement and potential of sensitivity analyses and automated model calibrations for regional conductive heat flow models on the basin scale, with an application to the Upper Rhine Graben in Central Europe.…”

Physical Properties of the Earth Crust Within the Joint Zone Between Turan Platform and Orogenic Structures of Tien-Shan

“…The density modeling is one of the important methods for the deep geological structure researches. Also, this method is very widespread in prospecting works for different minerals [19,20]. For example, there are a lot of works by this method in Russian hydrocarbon provinces [26,27].…”

“…Density modeling was provided for studying geodynamical and tectonic processes within the zones of the modern tectonic activity in different countries [19,20,30,32].…”

“…The second stage of the active orogeny mode is developed in the western termination of the Zeravshan ridge, southwest spurs of the Gissar Range, and, fragmentally, in Chatkal-Kurama and Turkestan-Alay system of raisings (types of crust 13,16,19,20) -see figure 1.…”