NAME_____________________
ES100 Introduction to Geology
Rindsberg
January 31 / February 1, 2022
Lab 3. Stratigraphic correlation
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.
(continued on next page)
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.
(continued on next page)
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.
Problem 2. Correlating strata using lithology (rock type).
Sections A through F represent the strata (rock layers) seen at six different outcrops. Different rock types are indicated by different graphic symbols, for instance, dotting represents sandstone. Draw lines to correlate the boundaries between strata (as shown). Note: Not every stratum (rock layer) is found in every outcrop.
Problem 3. Correlating strata with fossils.
Correlate the time lines (based on first appearances, FAs, of fossils) in this set of outcrops, whose fossils are characteristic of particular ages. The dark lines marked as 50, 70, and 100 Ma (Ma = millions of years ago) show levels at which absolute dates have been obtained. (To do this: Draw a line below the level where each kind of fossil first appears in a strat column. Then correlate the columns by drawing lines from FA to FA.)
Problem 4. Deducing the prehistory of the Grand Canyon.
Order the features and identify the event each feature represents. Make sure you can identify the stratigraphic principle(s) used to order each feature. The most recent event has been worked out for you.
Examples of possible events that may or may not be found: folding and uplift, faulting (related to extension or compression), sedimentation, igneous activity (related to convergence or extension), erosion, etc.
http://w3.salemstate.edu/~lhanson/gls100/lab_age/relativeage3sm.jpg
Feature (a, b, valley, etc.)
Event
Supporting Principle
gullies (youngest)
(oldest)
—
NAME_____________________
Introduction to Geology (ES100)
Rindsberg
January 31 / February 1, 2022
Lab 3. Stratigraphic correlation
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.
(continued on next page)
LC: Lateral Continuity: Sedimentary strata are