The Role of Lithospheric‐Deep Mantle Interactions on the Style and Stress Evolution of Arc‐Continent Collision

Abstract

Arc-continent collision is a multistage process by which intra-oceanic arcs may be accreted to continental margins, and it is considered the dominant mode of continental crust growth during Phanerozoic times (Brown et al., 2011;Rudnick and Gao, 2003). Arc-continent collision involves the following stages: (a) a subduction phase where the intra-oceanic arc crust grows while approaching the continental margin (Huang et al., 2000); (b) initial arc-continent collision where the arc arrives at the continental margin; (c) advanced arc-continent collision that results in the growth of a collisional orogen (Clift et al., 2003;Dewey, 2005;Huang et al., 2000); (d) full-accretion of the arc, namely arc transference from the subducting oceanic plate to the overriding continental plate, and (e) gravitational collapse of the orogenic root (Clift et al., 2003;Dewey, 2005). These stages are based on geological and geophysical observations from active examples such as Taiwan, Timor, and Papua New Guinea (Brown et al., 2011). However, this multistage process presents a large degree of variation in complexity, which mostly depends on the mechanical properties of the intra-oceanic arcs (Brown et al., 2011). Specifically, variations in the mechanical properties of intra-oceanic arcs may result in a wide range of collisional styles, which affect the geodynamics, the stress-strain evolution and the surface expression (Brown et al., 2011). Conceptual models based on temporal and spatially fragmented geological evidence suggest that initial and advanced arc-continent collision results in surface compression and orogenic growth, while the subsequent gravitational collapse stage