Figure 2.
Schematic cross sections showing inferred tectonic framework of the south-central Alaska segment of the Insular terrane during Late Jurassic–Early Cretaceous time.
(A) East-dipping model. Note inboard-dipping subduction beneath the Wrangellia-Peninsular terrane (i.e., Insular terrane) based on accretionary complex, forearc basin, magmatic arc elements, narrowing/closure of remnant ocean basin, and regional shortening/uplift during Early Cretaceous collision/accretion of the terrane. (B) West-dipping model, based on ideas presented in Sigloch and Mihalynuk (2017). This model does not explain the position of the Chugach accretionary complex relative to the arc rocks or the vergence of deformation within the marginal basins such as the Kahiltna. Modified from Trop and Ridgway (2007).