Geostatistical Methods for Geological Modeling and Hydrogeology with Isatis

Get acquainted with Geostatistics essential concepts for subsurface modeling

Objective

In many domains, like geotechnics, natural risks evaluation or optimization of acquisition networks in hydrogeology, it is of primary importance to base calculations on a realistic and accurate description of subsurface properties, accounting for their spatial heterogeneity.

This course presents the appropriate geostatistical methods for characterizing aquifers and building accurate numerical static models of subsurface. Focus is put on properties mapping in heterogeneous environments and on uncertainty assessment. Methods for modeling the spatial distribution of continuous variables (top/bottom of geological layers, petrophysical properties, mechanical or hydrogeological properties) and discrete ones (facies data) are detailed.

Format

Methodological presentations followed by practical computer exercises on real data sets using Isatis. Focus is made on the illustrations and the application of the presented concepts. Half of the course is dedicated to practical computer exercises in order to reinforce the previously presented theoretical notions.

Who should attend

This course is aimed at engineers, geologists and hydrogeologists confronted with the modeling of the subsoil heterogeneity and with the estimation of hydrogeological variables.

Content

Introduction

  • Current practices in geological modeling and hydrogeology.
  • Heterogeneity and uncertainty characterization.

Understanding and estimation of the spatial heterogeneity of the followed phenomenon

  • Practical introduction to the concepts of heterogeneity and spatial variability.
  • Quantification of the spatial variability: calculation and interpretation of the variogram.

Mapping a continuous variable (geological layer top, hydraulic head)

  • Deterministic interpolation methods.
  • Estimation by kriging (2D / 3D) and quantification of the attached uncertainty.
  • Consideration of auxiliary information: Digital Elevation.
  • Mapping with auxiliary data and/or fuzzy data.
  • Introduction to the conditional simulations for the quantifi cation of uncertainties.

Modeling of the geological heterogeneity

  • Presentation of simulation methods for discrete variables, in particular the plurigaussian and multipoint (MPS) simulations.
  • Post-processing of the results.

Controling permeable pathways distribution

  • Probabilistic maps.
  • Risk analysis.

Prerequisites

Have attended the course: “Geostatistics for Reliable Mapping with Isatis” or have a basic understanding of statistics / Isatis.