The Dead Sea area is increasingly facing serious subsidence and sinkhole hazards. On March 22, 2000, the dyke of a two-month old major salt evaporation pond, located along the shore of the Lisan Peninsula (Jordan), collapsed over almost two kilometers. The pond was set up over unstable new lands that have been progressively emerging during the last three decades. In one hour, 56 millions m 3 of brine poured out into the northern, natural part of the Sea. Here, we present data suggesting that the drop of the water level, in conjunction with the particular tectonic setting of this area, is at least one of the factors that led to the disaster. We focused our study over the northern part of the Lisan Peninsula and Ghor Al Haditha which are two places undergoing the most intense deformations along the Jordanian Dead Sea coast. We used the results of a static high precision gravimetric survey to detect subsurface cavities in Ghor Al Haditha. We analyzed a interferometric digital terrain model of the recent emerged platform of the Lisan peninsula and interpreted radar differential interferograms contemporary with gravity measurements for the peninsula. We discuss the possibilities to detect, assess and monitor areas prone to collapse on the Jordanian side of the southern Dead Sea coast.

Aeromagnetic data were analyzed to determine the Curie point depth (CPD) by power density spectral and threedimensional inversion methods within and surrounding Death Valley in southern California. We calculated the CPD for 0.5°r egions using 2D power density spectral methods and found that the CPDs varied between 8 and 17 km. However, the 0.5°region may average areas that include shallow and deep CPDs, and because of this limitation, we used the 3D inversion method to determine if this method may provide better resolution of the CPDs. The final 3D model indicates that the depth to the bottom of the magnetic susceptible bodies varies between 5 and 23 km. Even though both methods produced roughly similar results, the 3D inversion method produced a higher lateral resolution of the CPDs. The shallowest CPDs occur within the central and southern Death Valley, Panamint Valley, Coso geothermal field and the Tecopa hot springs region. Deeper ([15 km) CPDs occur over outcropping granitic and Precambrian lithologies in the Panamint Range, Grapevine Mountains, Black Mountains and the Argus Range. The shallowest CPD occurs within the central Death Valley over a possible seismically imaged magma body and slightly deeper values occur within the Panamint Valley, southern Death Valley and Tecopa Hot Springs. The shallow CPD values suggest that partially molten material may also be found in these latter regions. The CPD computed heat flow values for the region suggest that the entire area has high heat flow values ([100 mW m -2 ), on the other hand, locally extremely high values ([200 mW m -2 ) occur within the Panamint Valley, the southern and central Death Valley and Tecopa Hot Springs region. These locally high heat flow values may be related to midcrustal magma bodies; but additional geophysical experiments are needed to determine if the magma bodies exist.

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