Void detection is a difficult task for geophysical methods. The main disadvantage is the uncertainty of the final interpretation and the need for verification of the results with direct methods of underground investigation. A good way to reduce this uncertainty, apart from drilling, is through the implementation of more than one geophysical method in the same area. An integrated approach of geophysical methods can be achieved by using multiparameter statistical techniques, such as cluster analysis. Firstly, the effectiveness of multiparameter analysis on synthetic data is studied and then on real data from a controlled test site. In addition, a new approach for the creation of a unified geophysical model (UGM) is suggested to optimize target detection. Finally, the UGM approach is implemented and is evaluated in a real case study for void detection in an urban environment. The UGM offers the integrated information of the geophysical methods that are used without the need for predefined relationships. It is a model resulting from a specific statistical procedure, free of subjective precautions, and easily understood even by nonexperts in geophysics. Finally, it offers an additional tool for the better understanding of the subsurface as far as the difficult task of void detection is concerned.

This study presents a gravity survey conducted for mineral exploration in the Gerolekas overthrust area at a bauxite mining site in Central Greece. In the summer of 2018, a gravity survey, covering 28 km², was conducted, including confirmed and unexplored zones. By utilizing gravity data, we investigated the shallow subsurface geology and structural sequences, resulting in a high-resolution 3D density model. This model is generated through constrained gravity inversion by the exploitation of the boreholes available at mining sites, and the geological survey fills the areas with boreholes, which provides the stratigraphy to some depth. The suggested data-processing techniques provide information for the tectonism of the area, which is also important for mineral exploration, as well as mining design. The interface with density contrast between the flysch and the underlying limestone in the high-resolution 3D density model provides useful information on the geological status, but also, the slight density difference in limestone provides an interface where bauxite deposits can be. The inversion, conducted with EMIGMA software, incorporated high-resolution topography data and density constraints to produce a reliable 3D density model. The findings highlight the gravity method’s potential to enhance mineral exploration efficiency, offering a robust tool for further geological and mining considerations.