Condensed sections are thin stratigraphic intervals that represent considerable time. In some cases, these intervals include ferruginous particles such as oolitic ironstone. Here, García-Frank et al. document different iron-rich particles of Early to Middle Jurassic transition period, including the Fuentelsaz GSSP worldwide reference section, in the NW Iberian Range (Spain). The results, which integrate observations of mineralogy and REY (rare earth elements and yttrium), reveal a complex depositional, textural, and diagenetic history. Beyond providing new insights into the evolution of the westernmost Tethyan basins, these data motivate a conceptual model for the long-standing conundrum concerning the genesis of oolitic ironstones in condensed sections.
Iron-coated particles from condensed Aalenian–Bajocian deposits: evolutionary model (Iberian Basin, Spain) by Alejandra García-Frank, Soledad Ureta, and Ramón Mas