The northeastern Algeria hydrothermal system: gravimetric data and structural implication

Abstract

The Tell Atlas of Algeria has a huge potential for hydrothermal energy from over 240 thermal springs with temperatures up to $$98^\circ$$ 98 ∘ C in the Guelma area. The most exciting region is situated in the northeastern part which is known to have the hottest hydrothermal systems. In this work, we use a high-resolution gravity study to identify the location and origin of the hot water, and how it reaches the surface. Gravimetric data analysis shows the shapes of the anomalies arising due to structures at different subsurface depths. The calculation of the energy spectrum for the data also showcases the depths of the bodies causing anomalies. 3D-Euler deconvolution is applied to estimate the depths of preexisting tectonic structures (faults). These preprocessing steps assist with assessing signal attenuation that impacts the Bouguer anomaly map. The residual anomaly is used in a three-dimensional inversion to provide a subsurface density distribution model that illustrates the locations of the origin of the dominant subsurface thermal systems. Overall, the combination of these standard processing steps applied to the measurements of gravity data at the surface provides new insights about the sources of the hydrothermal systems in the Hammam Debagh and Hammam Ouled Ali regions. Faults that are key to the water infiltrating from depth to the surface are also identified. These represent the pathway of the hot water in the study area.

Editorial: Applications of gravity anomalies in geophysics

“…The third question is about mapping the structural lineaments (Ganguli and Pal; Sun et al) which is used widely in geological mapping (Altinoğlu, 2023;Ashraf and Filina, 2023;Bayou et al, 2023;Ibrahim et al, 2023;Lghoul et al, 2023;Mnasri et al, 2023;Qadir et al, 2023). Such applications are based on the qualitative interpretation of gravity anomalies in which the edge detection filters are usually applied to enhance the lineament.…”