This change is generally called deformation. When rocks are stressed, the resulting strain can be elastic, ductile, or brittle. Material C undergoes significant plastic deformation before finally brittle failure. Material B only elastically deforms before brittle failure. Material A has relatively little deformation when undergoing large amounts of stress, before undergoing plastic deformation, and finally brittle failure. Restart quiz 9.2 Deformation Different materials deform differently when stress is applied. Table showing types of stress and resulting strain: Type of StressДЄssociated Plate Boundary type (see Ch. Shear stress involves transverse forces the strain shows up as opposing blocks or regions of material moving past each other. Compressional stress involves forces pushing together, and compressional strain shows up as rock folding and thickening. Tensional stress involves forces pulling in opposite directions, which results in strain that stretches and thins rock. There are three types of stress: tensional, compressional, and shear. Strain in rocks can be represented as a change in rock volume and/or rock shape, as well as fracturing the rock. When applied stress is greater than the internal strength of rock, strain results in the form of deformation of the rock caused by the stress. Stress is the force exerted per unit area and strain is the physical change that results in response to that force. Clockwise from top left: tensional stress, compressional stress, and shear stress, and some examples of resulting strain. These forces are called stress, and the physical changes they create are called strain.В Forces involved in tectonic processes as well as gravity and igneous pluton emplacement produce strains in rocks that include folds, fractures, and faults.В When rock experiences large amounts of shear stress and breaks with rapid, brittle deformation, energy is released in the form of seismic waves, commonly known as an earthquake.

Describe notable historical earthquakesД¬rustal deformation occurs when applied forces exceed the internal strength of rocks, physically changing their shapes.

List earthquake factors that determine ground shaking and destruction.

Explain the difference between earthquake magnitude and intensity.

From seismograph records, locate the epicenter of an earthquake.

Describe how seismographs work to record earthquake waves.

Explain how humans can induce seismicity.

Describe different seismic wave types and how they are measured.

Explain how elastic rebound relates to earthquakes.

Differentiate the three major fault types and describe their associated movements.

Describe the geological map symbol used for strike and dip of strata.

Differentiate between brittle, ductile, and elastic deformation.Identify the three major types of stress.

Differentiate between stress and strain.Example of normal faulting in an outcrop of the Pennsylvanian Honaker Trail Formation near Moab, Utah.Д«y the end of this chapter, students should be able to:

Empire earth 4 9.5