 In contrast, the Laramide orogeny produced “basement-cored” uplifts that often took advantage of pre-existing faults that formed during rifting in the Late Precambrian during the breakup of the supercontinent Rodinia or during the Ancestral Rocky Mountains orogeny.The Sevier orogenic belt consisted of a series of thin plates along gently dipping west thrust sheets and moving from west to east.These thin skinned thrusts moved late Precambrian to Mesozoic age rock of the Cordilleran passive margin east.