Evolution and Propagation of an Active Plate Boundary: U‐Pb Ages of Fault‐Related Calcite From the Dead Sea Transform

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.

Syn-Tectonic Dolomite U-Pb Geochronology Constraining Intracontinental Deformation: A Case Study from the Gelouang Gold Deposit in the Qinling Orogen, China

“…Despite this, they are all formed by a crack-seal mechanism, and stepped sides indicate syn-kinematic growth. Such veins, especially crystals precipitation features, indicate the studied dolomite veins are syn-kinematic and occurred synchronously with movement along the fault plane [77][78][79][80]. Another key observation linking measured dolomite ages with specific fault motion is that the dolomite precipitation has not been altered or recrystallized, therefore, the explicitly the U-Pb isotopic system has not been reset [81].…”

Age, Kinematic and Thermal Constraints of Syn‐Orogenic Low‐Temperature Deformation Events: Insights From Thermochronology and Structural Data of the Nekézseny Thrust (Alpine‐Carpathian‐Dinaric Area)

“…As new mineral assemblages may grow or recrystallize within these fault rocks during fault slip (Niwa et al., 2016), the age of such syn‐kinematic minerals reflects the age of the fault movement itself. While in carbonatic sequences the most common syn‐kinematic calcite minerals can be dated by U‐Pb and U‐Th methods (Nuriel et al., 2012; Oren et al., 2020; Williams et al., 2019), K/Ar dating of K‐rich micas, such as illite, provide the best tools for dating siliciclastic fault rocks and fault gouges (Haines & van der Pluijm, 2008; Heineke et al., 2019; Kralik et al., 1987; Mancktelow et al., 2015, 2016; Pleuger et al., 2012; van der Pluijm et al., 2001; Yamasaki et al., 2013).…”