Limits...
High resolution multi-facies realizations of sedimentary reservoir and aquifer analogs.

Bayer P, Comunian A, Höyng D, Mariethoz G - Sci Data (2015)

Bottom Line: While this approach is appealing, it is difficult to put in place because of the lack of access to well-documented analog data.Multiple 2-D outcrop faces are described in terms of hydraulic, thermal and chemical properties and interpolated in 3-D using stochastic techniques.These unique data sets can be used by the wider community to implement analog approaches for characterizing reservoir and aquifer formations.

View Article: PubMed Central - PubMed

Affiliation: Department of Earth Sciences, ETH Zurich , Zurich 8092, Switzerland.

ABSTRACT
Geological structures are by nature inaccessible to direct observation. This can cause difficulties in applications where a spatially explicit representation of such structures is required, in particular when modelling fluid migration in geological formations. An increasing trend in recent years has been to use analogs to palliate this lack of knowledge, i.e., exploiting the spatial information from sites where the geology is accessible (outcrops, quarry sites) and transferring the observed properties to a study site deemed geologically similar. While this approach is appealing, it is difficult to put in place because of the lack of access to well-documented analog data. In this paper we present comprehensive analog data sets which characterize sedimentary structures from important groundwater hosting formations in Germany and Brazil. Multiple 2-D outcrop faces are described in terms of hydraulic, thermal and chemical properties and interpolated in 3-D using stochastic techniques. These unique data sets can be used by the wider community to implement analog approaches for characterizing reservoir and aquifer formations.

Show MeSH

Related in: MedlinePlus

Outcrop photographs of Descalvado (a) and Herten (b) profiles taken at the gravel pits during excavation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4493827&req=5

f2: Outcrop photographs of Descalvado (a) and Herten (b) profiles taken at the gravel pits during excavation.

Mentions: Both analog data sets are reconstructed rectangular blocks of unconsolidated sediments, which are mapped by several (5–6) outcrop cross sections in the field and supported by laboratory measurements (Fig. 1). Each data gathering campaign took around six months, synchronized with the mining activities in the sand and gravel pits. The fluvial-glacial sediments of the Rhine valley were excavated close to the town of Herten (Herten-analog) in the summer of 199911,32, and the fluvio-aolian deposits in Brazil close to the town of Descalvado (Descalvado-analog) in 201131 (Table 1). Outcrop photographs are shown in Fig. 2. Both case studies were mainly motivated from hydrogeology: the young Rhine gravels host among the most productive aquifers in central Europe, and the Brazilian Pirambóia formation belongs to those sequences that store the most important groundwater reservoir in South America, the Guarani Aquifer system (GAS). The original descriptions of highly resolved hydraulic and hydrochemical heterogeneity and earlier interpolated blocks hence served as aquifer analogs in several previous groundwater modelling and model inversion studies17,19,20,22,28,42,43. For instance, Maji and Sudicky42 implemented the Herten analog in a numerical flow and transport model with decimetre-grid resolution to examine the solution of dense nonaqueous phase liquids (DNAPL) in sedimentary aquifers. Werth, et al.17 demonstrated with one Herten cross section, how contaminant mixing and flow focusing is controlled by typical sedimentary structures. Kowalsky, et al.23, Jiménez, et al.43 and Hu, et al.22 chose Herten profiles for developing and validating new geophysical and tomographical field investigation techniques. In these studies, the analog served to set up a realistic but computer-based virtual aquifer. In comparison to experiments in the field, computer experiments are less costly and, more importantly, can be validated using a reference where all hydraulic, thermal or chemical details are known. Our work offers new 3-D realizations of the Herten-analog, for the first time 3-D interpolations of the Descalvado-analog and a combined resolution of four different facies types. To our knowledge, there are currently no analog datasets publicly available with comparable multiple parameter characterizations of such sediment bodies.


High resolution multi-facies realizations of sedimentary reservoir and aquifer analogs.

Bayer P, Comunian A, Höyng D, Mariethoz G - Sci Data (2015)

Outcrop photographs of Descalvado (a) and Herten (b) profiles taken at the gravel pits during excavation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4493827&req=5

f2: Outcrop photographs of Descalvado (a) and Herten (b) profiles taken at the gravel pits during excavation.
Mentions: Both analog data sets are reconstructed rectangular blocks of unconsolidated sediments, which are mapped by several (5–6) outcrop cross sections in the field and supported by laboratory measurements (Fig. 1). Each data gathering campaign took around six months, synchronized with the mining activities in the sand and gravel pits. The fluvial-glacial sediments of the Rhine valley were excavated close to the town of Herten (Herten-analog) in the summer of 199911,32, and the fluvio-aolian deposits in Brazil close to the town of Descalvado (Descalvado-analog) in 201131 (Table 1). Outcrop photographs are shown in Fig. 2. Both case studies were mainly motivated from hydrogeology: the young Rhine gravels host among the most productive aquifers in central Europe, and the Brazilian Pirambóia formation belongs to those sequences that store the most important groundwater reservoir in South America, the Guarani Aquifer system (GAS). The original descriptions of highly resolved hydraulic and hydrochemical heterogeneity and earlier interpolated blocks hence served as aquifer analogs in several previous groundwater modelling and model inversion studies17,19,20,22,28,42,43. For instance, Maji and Sudicky42 implemented the Herten analog in a numerical flow and transport model with decimetre-grid resolution to examine the solution of dense nonaqueous phase liquids (DNAPL) in sedimentary aquifers. Werth, et al.17 demonstrated with one Herten cross section, how contaminant mixing and flow focusing is controlled by typical sedimentary structures. Kowalsky, et al.23, Jiménez, et al.43 and Hu, et al.22 chose Herten profiles for developing and validating new geophysical and tomographical field investigation techniques. In these studies, the analog served to set up a realistic but computer-based virtual aquifer. In comparison to experiments in the field, computer experiments are less costly and, more importantly, can be validated using a reference where all hydraulic, thermal or chemical details are known. Our work offers new 3-D realizations of the Herten-analog, for the first time 3-D interpolations of the Descalvado-analog and a combined resolution of four different facies types. To our knowledge, there are currently no analog datasets publicly available with comparable multiple parameter characterizations of such sediment bodies.

Bottom Line: While this approach is appealing, it is difficult to put in place because of the lack of access to well-documented analog data.Multiple 2-D outcrop faces are described in terms of hydraulic, thermal and chemical properties and interpolated in 3-D using stochastic techniques.These unique data sets can be used by the wider community to implement analog approaches for characterizing reservoir and aquifer formations.

View Article: PubMed Central - PubMed

Affiliation: Department of Earth Sciences, ETH Zurich , Zurich 8092, Switzerland.

ABSTRACT
Geological structures are by nature inaccessible to direct observation. This can cause difficulties in applications where a spatially explicit representation of such structures is required, in particular when modelling fluid migration in geological formations. An increasing trend in recent years has been to use analogs to palliate this lack of knowledge, i.e., exploiting the spatial information from sites where the geology is accessible (outcrops, quarry sites) and transferring the observed properties to a study site deemed geologically similar. While this approach is appealing, it is difficult to put in place because of the lack of access to well-documented analog data. In this paper we present comprehensive analog data sets which characterize sedimentary structures from important groundwater hosting formations in Germany and Brazil. Multiple 2-D outcrop faces are described in terms of hydraulic, thermal and chemical properties and interpolated in 3-D using stochastic techniques. These unique data sets can be used by the wider community to implement analog approaches for characterizing reservoir and aquifer formations.

Show MeSH
Related in: MedlinePlus