Surface and Subsurface Investigations for the Detection and Mapping of Underground Karst Cavities in MChentel Area, Cheria Basin, Northeast of Algeria

Abstract

A combined approach using the surface geophysical method (microgravimetric survey) and sub-surface investigations (speleology) was undertaken at an experimental karst site located in the MChentel area near Cheria town (Northeast of Algeria). The gravimetric survey, carried out by a gravimeter GNU-KC 444 during March-April 2016, allowed the procurement of 614 gravimetric measurements distributed on the whole of the zone of study. The gravimetric data shows a reduction in the values of the Bouguer anomaly between two collapses. This trend probably implies an effect of karstification that would explain the reduction in the values of the Bouguer anomaly while moving towards the centre of the zone of study. The results provided in this work of underground exploration by the team of speleologists from Polytechnic Nice-Sophia in 2013 and 2014 are particularly well illustrated by the topography of the cavities upstream and the real photographs, the micromorphology and the microstructures of the walls of the cavities explored. The joint application of the microgravimetry and speleology make it possible to evaluate the advantages and effectiveness of the microgravimetry for the detection of underground cavities. This improves knowledge of the karstic system structure of Eocene carbonates in the studied area.

Establishment and Application of the Spatial Decomposition Method (SDM) for Tunnels Passing Through Large Karst Caves

“…Line b is located inside the rock mass and is not visible; thus, it cannot be measured directly. In order to accurately estimate the thickness of the unstable surrounding rock, a coring survey method is adopted [27][28][29][30][31]. The same section is selected for the coring survey and laser ranging, but it is more difficult and time-consuming to acquire high-density coring survey points compared to performing laser ranging, and the detection accuracy is limited.…”

A Novel Metaheuristic Strategy for the Elucidation of Gravity Anomalies with Application to Geothermal Energy Investigations and Volcanic Activity Studies: Hunger Games Search (HGS)

“…The gravity method in geophysics, a traditional, passive, non-invasive, and costefficient method, measuring the variation in the Earth's gravitational field caused by the difference of rock mass properties at a certain position, has been applied in a large spectrum of projects such as ore/mineral exploration (Hinze, 2013;Chen et al, 2015;Li et al, 2019; Essa and Abo-Ezz, 2021) [1][2][3][4] , archaeology investigation (Branston and Styles, 2006;Batayneh et al, 2010; Sarlak and Aghajani, 2017) [5][6][7] , radioactive waste management (An et al, 2013) [8] , weapons and unexploded ordnances detection (Abedi et al, 2014) [9] , Hydrocarbon/reservoir (oil and gas) recognition (Yuan et al, 2018; Saghafi and Yarveicy, 2019; Cho et al, 2020) [10][11][12] , geothermal energy and volcanic activity study (Altwegg et al, 2015; Uwiduhaye et al, 2018; Essa and Diab, 2022) [13][14][15] , underground cavities or tunnels identification (Pazzi et [16][17][18] , geotechnical and engineering application (Debeglia and Dupont, 2002;Arisona et al, 2018) [19,20] , groundwater monitoring (Frappart and Ramillien, 2018; Delobbe et al, 2018) [21,22] , landfills mapping (Silva et al, 2009;Dumont et al, 2017) [23,24] , subsurface structures imaging...…”

Fault parameters assessment from the gravity data profiles applying the global particle swarm optimization

“…The gravity method is a non-invasive, cost-efficient and passive method, which measures the difference in the Earth's gravitational field at a certain location, caused by the rock mass properties (density). It has been applied in a wide range of projects such as hydrocarbon (oil and gas) exploration (Yuan et al, 2018;Saghafi and Yarveicy, 2019;Cho et al, 2020), underground cavities or tunnels detection (Pazzi et al, 2018;Abdullah et al, 2019;Saddek et al, 2019), geothermal exploration (Altwegg et al, 2015;Uwiduhaye et al, 2018), geotechnical and engineering application (Debeglia and Dupont, 2002;Arisona et al, 2018), weapons and unexploded ordnances inspections (Abedi et al, 2014), archaeology investigation (Branston and Styles, 2006;Batayneh et al, 2007;Sarlak and Aghajani, 2017), monitoring of ground water (Frappart and Ramillien, 2018;Delobbe et al, 2019), mineral and ores exploration (Hinze, 1960;Chen et al, 2015;Essa and Abo-Ezz, 2021), landfills mapping (Silva et al, 2008;Gaël et al, 2017), radioactive waste management (An et al, 2013), mapping of subsurface structures (Chakravarthi et al, 2017;Deng et al, 2016;.…”