Dynamics of hydrological and geomorphological processes in evaporite karst at the eastern Dead Sea – a multidisciplinary study

Abstract

Abstract. Karst groundwater systems are characterised by the presence of multiple porosity types. Of these, subsurface conduits that facilitate concentrated, heterogeneous flow are challenging to resolve geologically and geophysically. This is especially the case in evaporite karst systems, such as those present on the shores of the Dead Sea, where rapid geomorphological changes are linked to a fall in base level by over 35 m since 1967. Here we combine field observations, remote sensing analysis, and multiple geophysical surveying methods (shear wave reflection seismics, electrical resistivity tomography [ERT], self-potential [SP] and ground penetrating radar [GPR]) to investigate the nature of subsurface groundwater flow and its interaction with hypersaline Dead Sea water on the rapidly retreating eastern shoreline, near Ghor Al-Haditha in Jordan. Remote-sensing data highlight links between the evolution of surface stream channels fed by groundwater springs and the development of surface subsidence patterns over a 25-year period. ERT and SP data from the head of one groundwater-fed channel adjacent the former lakeshore show anomalies that point to concentrated, multidirectional water flow in conduits located in the shallow subsurface (

A decade-long silent ground subsidence hazard culminating in a metropolitan disaster in Maceió, Brazil

“…We discuss the accelerating subsidence rates, influence of severe precipitation events on the aforementioned geological instability, and related hazards. This study suggests that feedback destabilization mechanisms may arise in evaporite systems due to anthropogenic activities, fostering enhanced and complex superficial ground deformation.Land subsidence affects many highly populated urban areas of the world, either as a consequence of extensive groundwater depletion, such as in Tehran 1,2 , Las Vegas 3 , Beijing 4 , and Tucson 5 , as a combined effect of loading and compaction of unconsolidated lacustrine sediments, such as in Mexico City 6,7 , or via construction dewatering 8 and underground mining [9][10][11] .However, naturally or anthropogenically induced evaporite dissolution with consequent ground subsidence also occurs in several parts of the world, such as the salt dissolution cases of the Permian and Triassic evaporitic terrain in the UK 12 , numerous Triassic and Tertiary evaporite areas in Spain 13 , Quaternary sediment subrosion in the Dead Sea [14][15][16] and many areas underlying the Permian basin in the United States 17,18 . Evaporite dissolution and consequent ground subsidence pose a severe geohazard for overlying urban areas, such as Zaragoza city in Spain 19 , Tuzla in Bosnia and Herzegovina 20 , and Wieliczka in Poland 21 .In particular, salt (halite, or NaCl) is the most soluble evaporite rock that is widespread in continental regions.…”

“…However, naturally or anthropogenically induced evaporite dissolution with consequent ground subsidence also occurs in several parts of the world, such as the salt dissolution cases of the Permian and Triassic evaporitic terrain in the UK 12 , numerous Triassic and Tertiary evaporite areas in Spain 13 , Quaternary sediment subrosion in the Dead Sea [14][15][16] and many areas underlying the Permian basin in the United States 17,18 . Evaporite dissolution and consequent ground subsidence pose a severe geohazard for overlying urban areas, such as Zaragoza city in Spain 19 , Tuzla in Bosnia and Herzegovina 20 , and Wieliczka in Poland 21 .…”