Rocks for Jocks: Preconceptions about the Earth

John E. DeLaughter (Dept. of Geological SciencesNorthwestern University, Evanston, IL)
Seth Stein (Dept. of Geological SciencesNorthwestern University, Evanston, IL)
Carol Stein (Dept. of Earth and Environmental SciencesUniversity of Illinois at Chicago, Chicago, IL)
Kenneth R. Bain (Searle Center for Teaching ExcellenceNorthwestern University, Evanston, IL)

This site contains data relating to a paper published in the August 25, 1998, issue of Eos.


Assessment of the success of any educational technology requires analysis of what students know bother before and after a course. Studies have shown that many students enter introductory physics courses with misconceptions which are often unchanged reguardless of teaching method. To see whether such misconceptions are commonly held by introductory geology students, we gave an “earth science literacy” test to 149 students at the University of Illinois at Chicago taking an introductory geology course.


Earth Science Literacy Test









The test population

Freshman 40 27%
Sophmore 50 34%
Junior 36 24%
Senior 15 10%
Other 8 5%

Total: 149

Education 27 18%
Liberal Arts 62 42%
Science 37 25%
Engineering 5 3%
None/Undecided 18 12%

Science majors were predominantly in psychology and anthropology; no geology majors were in this group.


Last Geology Class:
High school 89 60%
College 8 5%
None 52 35%
Last Math Class:
High school 40 27%
College 108 72%
None 1 1%

Typical college math classes included pre-algebra and introductory calculus.

Last Physics Class:
High school 94 63%
College 12 8%
None 43 29%
Last Chemistry Class:
High school 102 68%
College 28 19%
None 19 13%


The results of the test


General Science Questions

Earth Science Questions

Timescale Questions

Astronomy Questions

Physics Questions



  • Most students described Earth as a layered planet; however, many believed that there exists a magma layer within Earth.
  • Most students stated that earthquakes reflect the movement of subterranean plates. Most believe that volcanism derives from excess heat and/or pressure, often within Earth’s core. Both processes were frequently associated with warmer climates and the ocean.
  • Many students attribute the Mid-Atlantic Ridge to a rise in water levels. Few gave seafloor spreading as a cause; many believe it is due to a collision of two plates.
  • Equal numbers of students put the extinction of the dinosaurs before 1 Ma and between 10 and 90 Ma. Many students placed the beginning of at a few Ga, but a significant number placed it before 1 Ma. Though most gave the age of Earth as a few Ga, 23% of the responses to all three questions included a logical contradiction (e.g., the dinosaurs becoming extinct before life arose).
  • Most students believe global warming is due to destruction of the ozone layer; few cited increased CO2.
  • More than half of the students believe that salt melts ice by a chemical reaction.
  • As in the famed Harvard study, most students attributed the seasons to the distance of Earth from the Sun.

This test will be refined to better understand students’ geological preconceptions and to evaluate the effectiveness of teaching methods.


Related Links

The Eos article

Our geophysics concepts demonstration page

This site was selected as the Virtual Geoscience Professor’s Site of the Fortnight for October 5, 1998.