INTERPRETING ROCK STRATA: LEVEL 2
Name:_____________________ Per. _____
In addition to intrusions, other disturbances can happen to rock strata. They include:
See p. 61 for
more info.
•
A fault is a break in the Earth’s crust that forms due to tectonic plate movement. Rock layers can shift
along the fault. A fault is younger than the layers of rock it cuts across.
•
Folding and tilting occur when rock layers are shifted from their normal horizontal positions by
pressure and stress (primarily caused by tectonic plate movement). Folding and tilting are younger
events than the rock layers they impact.
Also, rock layers can be missing due to weathering and erosion. We call this an
unconformity and indicate this using a wavy line.
Unconformity
For each of the following problems, apply these rules to figure out the order of
geologic events from youngest to oldest. Note: it is often easiest to start with the oldest layer and work your
way to the youngest. In some problems, you’re provided some hints:
1.
Youngest
__________________
__________________
__Folding M
__________________
Folding M
Layer X
Oldest
2.
Youngest
__________________
Fault V
__________________
__________________
Layer L
__________________
_________________ Oldest
__________________
__________________
Layer F
__________________
__________________
Some problems modified from HBJ material and http://www.geosociety.org/educate/LessonPlans/Relative_Age.pdf
Folding M
3. Youngest
__________________
Layer E
__________________
__________________
Intrusion
__________________
__________________
__________________
Layer C
Oldest
__________________
Layer U
Fault B
4. Youngest __________________
__________________
__________________
__________________
__________________
__________________
__________________
__________________
__________________
Oldest
__________________
5. Youngest __________________
__________________
__________________
__________________
__________________
__________________
__________________
__________________
__________________
Oldest
__________________
6. Now make up your own problem and show the solution. Draw and label neatly (see Ms. VH for blank paper).
The most challenging entries will qualify for a chance to earn an “Exceptional” mark on this learning target on
our test (and might be used for challenge problems on the test itself).