Problem 1. Using principles of stratigraphy to deduce the order of past events.
Order the features and identify the event each feature represents. Identify the principle(s) used to order each feature, using the abbreviations in the list.
Feature (b, c, d, or e) Event Supporting Principle
4 (youngest)
3
2
1 (oldest)
Examples of possible events that may be found: folding and uplift, faulting, sedimentation, igneous activity, erosion, etc.
Stratigraphic Principles include:
OH: Original Horizontality: Sedimentary strata are laid down almost horizontally. If they are not horizontal now, then they must have been tilted, folded, or otherwise moved or deformed.
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LC: Lateral Continuity: Sedimentary strata are laid down continuously over large areas unless confined in a basin. For instance, when snow falls, it falls evenly over a broad area.
SU: Superposition: In a stack of strata, the youngest layer is the one on top.
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CR: Cross-cutting Relations: If a body of rock, or a break such a fault, crosses a stratum, then the stratum must already have been in existence.
IN: Inclusions: If a stratum contains a pebble, fossil, or other inclusion, then the inclusion must have already existed.
FS: Faunal Succession: Different kinds of fossils occur at particular intervals within the world’s “stack” of strata.