LATE CENOZOIC THERMAL GRADIENTS IN DEAD SEA TRANSFORM SYSTEM BASINS

Coal‐rank measurements and heat‐flow data from three rhomb‐shaped grabens along the continental portion of the Dead Sea Transform—the Hula Depression, the Sea of Galilee and the Dead Sea Graben—reveal contrasting thermal regimes. The coalification profile the Hula Depression indicates a relatively high thermal gradient, averaging 40d̀C/km, throughout the Late Cenozoic. Similarly, a relatively high heat flow, approx 1.77 HFU, was reported in the Sea of Galilee, 35 km to the south. Coalfieation profile, heat flow data and BHT measurements on the Dead Sea Graben (200 km to the south) reveal a considerably lower thermal regime (approx 0.7 HFU, 2Od̀C/km) that has prevailed since the mid‐Miocene. However, the differences in the thermal regime do not represent different mechanisms of basin formation. With the corroboration of hydrological and geophysical data, it is suggested that the high thermal regime in the two northern basins reflects a regional phenomenon associated with the nearby extensive Golan‐Jeble Druze young volcanic terrain. Therefore, it has no relationship to the mechanism of rhomb‐shaped graben formation, and should not be cited in support of kinematic models requiring a high thermal regime.