If horizontal sedimentary strata overlie tilted strata (and no fault is present),the surface between the horizontal and tilted strata must be a(n)
A) conformable sedimentary contact.
B) angular unconformity.
C) disconformity.
D) nonconformity.

Question

Quizplus · Accepted Answer

If horizontal sedimentary strata overlie tilted strata, it suggests a period of deformation or uplift occurred after the tilted strata were deposited. Therefore, the boundary between the tilted and horizontal strata is not a conformable sedimentary contact but an unconformity. Since there is angular discordance between the two sets of strata, it is an angular unconformity. A disconformity occurs between parallel sedimentary strata where there is a break in sedimentation, but no tilting or deformation has occurred. A nonconformity occurs when sedimentary rock lies upon eroded metamorphic or igneous rock.

If Horizontal Sedimentary Strata Overlie Tilted Strata (And No Fault