Biology Forums - Study Force

Compare and contrast the three types of unconformities. What differences in geologic history do these three types
  imply? What will be an ideal response?

The student should recognize that angular unconformities imply a period of no sedimentation
in which deformation and possible mountain building occur with later erosion to create the
unconformity level. By contrast, a nonconformity represents a surface in which younger
sedimentary strata overlie much older igneous or metamorphic rocks. A disconformity
implies a period of erosion or nondeposition during which little deformation occurs. t is also
the most difficult to recognize because layers above and below the unconformity may have
the same sedimentary texture and composition but differ only in age