Relier Pairs Forces on EarthVersion en ligne This activity will assist you with learning the stresses placed on Earth's crust. Match the descriptions to the pictures. par sandra mccullough 1 The upward fold in a mountain due to compression 2 The process where rock layers bend under stress. 3 The bottom fold of a mountain as a result of compression. 4 The stress that pushes rocks in parallel but opposite directions. 5 Stress that stretches or pulls rock. 6 Stress that squeezes rock together. 7 The process by which rocks change shape when under stress.