Rheological decoupling at the Moho and implication to Venusian tectonics.

Plate tectonics is largely responsible for material and heat circulation in Earth, but for unknown reasons it does not exist on Venus. The strength of planetary materials is a key control on plate tectonics because physical properties, such as temperature, pressure, stress, and chemical composition, result in strong rheological layering and convection in planetary interiors. Our deformation experiments show that crustal plagioclase is much weaker than mantle olivine at conditions corresponding to the Moho in Venus.

Uranium-236 as a new oceanic tracer: A first depth profile in the Japan Sea and comparison with caesium-137.

We present a feasibility study for using U as an oceanic circulation tracer based on depth profiles of U and Cs in the Japan/East Sea. The concentration of the predominantly anthropogenic U, measured with Accelerator Mass Spectrometry (AMS), decreased from (13±3)×10 atom/kg in surface water to (1.6±0.