ConcepTest: Sedimentary Rock Formation

ConcepTest questions by David McConnell, David Steer , Walter Borowski, Jeffrey Dick, Annabelle Foos, Jeffrey Knott, Alvin Konigsberg, Michelle Malone, Heidi McGrew, Kathie Owens, and Stephen Van Horn

This material was originally created for Starting Point:Introductory Geology
and is replicated here as part of the SERC Pedagogic Service.

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

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).