Extended Data Fig. 10: Summary geodynamic model for Hess plateau subduction and diachronous onset of slab flattening leading to water fluxed crustal anatexis.
From: Porphyry copper formation driven by water-fluxed crustal melting during flat-slab subduction
a-b) Global plate reconstructions of the Hess conjugate showing the oblique intersection with the trench at ~75–70 Ma causing diachronous slab-flattening towards the SE. Data from refs. 20,21,119. c) Map of Western USA with sequential ‘sweet-spot’ advance related to slab geometry. Data from refs. 3,17,23,26,47,51,52. d) Cartoon block model showing the geometric relationship of the Cu ‘sweetspot’ on the leading edge of the flat-slab relative to the conjugate Hess subduction. e) Schematic crustal temperature distribution for a 2-D flat-slab at the hypothesized ‘sweetspot’ based on the new pressure-temperature data and Orocopia Schist data49,50,51; note the inverted isotherms on the trench-ward side of the ‘sweetspot’ due to continued underthrusting of a flat-slab causing cooling of the upper-plate. f) Schematic pressure-temperature phase diagram showing the decrease in granitic solidus with increasing addition of water. Data from ref. 61.
