K-Ar (40Ar/39Ar) Geochronology of Ultrahigh Pressure Rocks

  title={K-Ar (40Ar/39Ar) Geochronology of Ultrahigh Pressure Rocks},
  author={St{\'e}phane Scaillet},
Although 40Ar/39Ar dating studies have been successful in setting age constraints on many ultrahigh pressure (UHP) occurrences world-wide, argon isotopic data from UHP rocks have on occasion proven difficult to interpret in terms of cooling and exhumation ages. One principal reason is that the closure behavior of common, high-K rock-forming minerals (phengite, phlogopite, and biotite) is poorly understood in UHP contexts, with age variations occurring at the scale of a single outcrop—or even a… CONTINUE READING