Growth of Neogene Andes linked to changes in plate convergence using high-resolution kinematic models.

The Andean cordillera was constructed during compressive tectonic events, whose causes and controls remain unclear. Exploring a possible link to plate convergence has been impeded by the coarse temporal resolution of existing plate kinematic models. Here we show that the Neogene evolution of the Andean margin is primarily related to changes in convergence as observed in new high-resolution plate reconstructions.

Metal concentrations and source identification in Chilean public children's playgrounds.

This study is focused on four Biobio region cities, Concepcion, Talcahuano, Los Ángeles, and Tomé; these cities flourished very close to different industrial activities. We determined a pseudo total concentration of seven heavy metals (Cr, Ni, Cu, Zn, As, Cd, and Pb) in playground soils through inductively coupled plasma-mass spectrometry (ICP-MS). Principal components analysis (PCA) revealed that contamination in soils comes from three principal sources.