The changes in crustal strains are then interpreted as recording a progressive change in relative motions between the Pacific Ocean basin and North America and suggest a transition from Late Jurassic sinistral deformation to Early Cretaceous dextral terrane translations along the paleo-Pacific margin. These progressive strain reorientations are interpreted in terms of an outboard Wallowa-Baker terrane collision, lateral extrusion, docking of the amalgamated Blue Mountains superterrane into a continental-margin reentrant, and onset of oroclinal bending, respectively. 126 Ma (in the Wallowa oceanic arc terrane). 140 Ma onward and was associated with progressive anticlockwise rotation of the principal horizontal shortening direction from ca. 147 Ma (in the forearc–accretionary wedge Baker terrane), to (3) dextral transpression that started from ca. 160 Ma, to (2) horizontal stretching at ca. The inferred strain regimes changed from: (1) thrusting and sinistral shearing at ca. Contrasting magnetic fabrics in five successively emplaced syntectonic plutons reveal temporal and spatial variations in tectonic strain in the oceanic terranes of the Blue Mountains province, northeastern Oregon, during the Late Jurassic to Early Cretaceous.
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