Evolution and Propagation of an Active Plate Boundary: U‐Pb Ages of Fault‐Related Calcite From the Dead Sea Transform
Omer Oren, Perach Nuriel, Andrew Kylander‐Clark, Itai Haviv
Abstract
Abstract We utilize in situ U‐Pb geochronology of fault‐related calcite to date faulting activity along the Dead Sea Transform (DST) plate boundary and constrain the evolution of continental breakup. U‐Pb ages from 30 well‐constrained Tera‐Wasserburg data sets of syntectonic calcite precipitates along the northern part of the DST delineate two key periods of faulting activity: (1) Maastricht (latest Cretaceous) to Eocene (70–37 Ma) and (2) middle Miocene (18–10 Ma). The latter period is more extensive and is associated with normal and left‐lateral shearing deformation. Ages of ~18 Ma, obtained from the western and eastern most strands (~20 km apart), indicate that branching in the northern DST occurred during the initial stage of the DST development. Comparison of the new ages from the northern part of the DST with U‐Pb ages from the southern part highlights prominent faulting activity during the early to middle Miocene (20–10 Ma), with earliest ages of ~18 Ma in the south and younger ages of ~14 Ma in the north. This pattern suggests that the genesis of this plate boundary started adjacent to the Red Sea rift and migrated from south to north during a 3.5–4 Ma period (between 18 and 14 Ma) at an average rate of 11–13 cm/year. Such propagation data can be used to decipher the mechanical evolution of the lithosphere along evolving plate boundaries.