Post-doctoral position modeling of spatial fields in geosciences H/F

Détail de l'offre

Informations générales

Référence

2019-1423  

Description du poste

Métier

F11 Géotechnique - Expert·e scientifique

Intitulé du poste

Post-doctoral position modeling of spatial fields in geosciences H/F

Contrat

CDD

Temps de travail

Temps complet

Durée du contrat

12 mois

Description de la mission

As the French Geological Survey, BRGM is the reference public organization in the area of geosciences in France (www.brgm.fr). Its missions include scientific research, support to public policies and international cooperation.

After a preliminary phase to learn how to use the available tools, the objective of the post-doctoral work is to test the relevance and evaluate the contribution of these new methods on two real cases, taken from BRGM's activities:
- in hydrogeological modeling (interpolation of large number of piezometries and modeling of a pollutant plume)
- in geological modeling (interpolation of geological interfaces with inequality constraints and simulations / interpolations of a complex geological model)
Short articles, possibly submitted for scientific communications, will summarize the work carried out on each of these two case studies along with the main results.

The post-doctoral fellow will use the R-Geostat library (http://rgeostats.free.fr/) developed by the Center for Geoscience from Mines Paristech. A training period at Fontainebleau is planned at the beginning of the contract period. The first case (hydrogeological modeling) lends itself well to a direct application of the available tools while the second (geological modeling) may require some adaptations of the available algorithms.

The work will take place at the BRGM in Orléans in close collaboration between the Géoresources, Risks and Prevention, and Eau Environnement departments, as well as with the ISTO (Institute of Earth Sciences of Orléans). It will also include exchanges with the Paristech Mines Geoscience Center in Fontainebleau.

Contexte

Kriging and conditional simulations have become classical tools in the field of geosciences. They are used routinely to study the spatio-temporal distribution of physical properties: petrophysical parameters (hydraulic conductivity, porosity ...), contaminant concentrations, field measurements (hydraulic head, temperature ...)... Geostatistics provides an elegant framework to quantify the uncertainty associated with such phenomena (variability), and is at the heart of many BRGM activities.

Under certain assumptions, the recent recast of these issues in the framework of SPDE (Stochastic Partial Derivative Equations - cf the work by Lindgren et al. 2011), allows to unlock a considerable number of usual limitations of the traditional kriging approaches that revolve around solving large dense linear system. It is now possible to envisage the application of these new methods to large datasets, taking into account local anisotropies ... The numerical performances obtained are also spectacular and allow to consider the generation of a large number of simulations, conditioned to observations, and thus, a systematic and automated study of uncertainties.

Profil

You've been holding a Ph.D thesis for less than 5 years with a specialty in spatial statistics, geostatistics and / or applied probabilities. You have a first experience of geostatistical tools and methods and have at least a first experience in scientific programming (R, Python ...).

Vous mobiliserez les compétences et qualités suivantes :
- Substantial background in geostatistics / probabilities / spatial statistics,
- Knowledge of a scripting language - ideally R,
- A strong motivation for applied work in the field of geosciences,
- Writing and oral skills,
- Anaytical and synthetical mind,
- Team spirit.

Spécificité du poste

This full-time position involves some travel (Mines Paristech in Fontainebleau and participation in at least one international conference).

Each post will be subjected to an open process of recruitment, including people with disabilities, in wich the main criterion will be te quality of the candidature. Please send a curriculum and cover letter to 31/08/19.

Localisation du poste

Localisation du poste

France, Centre-Val de Loire, Loiret (45)

Ville

Orléans