An ArcGIS approach to include tectonic structures in point data regionalization.

Area of Science:

• Hydrogeology
• Geostatistics
• Geology

Background:

• Regionalizing point data from drilling logs is essential for aquifer characterization.
• Tectonic structures like faults can cause discontinuities in aquifers, complicating spatial interpolation.
• Existing methods struggle to effectively incorporate these structural complexities into regionalization.

Purpose of the Study:

• To develop and test a novel approach for regionalizing aquifer data that accounts for neotectonic structures.
• To improve the accuracy of aquitard mapping in areas with significant geological discontinuities.
• To provide a practical method for incorporating fault-induced offsets into groundwater models.

Main Methods:

• Combined ordinary kriging (using variograms) with inverse distance weighting (IDW) interpolation.
• Utilized breaklines and buffer zones to represent tectonic faults and their impact on aquitard continuity.
• Applied the methodology to the largest porous aquifer in Austria, characterized by neotectonic basins and faults.

Main Results:

• Successfully generated an aquitard map that accurately represents discontinuous surface structures caused by tectonic faults.
• The combined geostatistical approach effectively handled abrupt changes in aquitard elevation due to fault offsets.
• Demonstrated the feasibility of integrating neotectonic structures into standard GIS software (ArcGIS) for regionalization.

Conclusions:

• The proposed method effectively regionalizes point data in the presence of significant neotectonic structures.
• This approach offers a valuable tool for hydrogeologists and groundwater modelers dealing with complex geological settings.
• The technique is adaptable for practical applications in aquifer management and resource assessment.