ConcepTest: Sedimentary Rock Formation
Question:
Concrete is formed by adding cement and water to a mixture of sand and gravel. This could be seen as an analog for the formation of a ___________ sedimentary rock.
a. clastic
b. chemical
c. biochemical
a. clastic
b. chemical
c. biochemical
Student Responses:
The correct response is A.
Percentage of students choosing this answer. (% Before Discussion/% After Discussion):
a. clastic (59%/81%)
b. chemical (22%/4%)
c. biochemical. (19%/15%)
in a small (< 60 students) environmental geology class.
If you would like to help acquire more Before and After statistics for this example, please contact the authors (see link at top of page).