top
On the Back of an Envelope  Triplehorn 

A column in the Journal of Geological Education.
On the Back of an Envelope: A column devoted to encouraging
calculation in geology
Triplehorn, Don
A column in the Journal of Geological Education.
1994 v. 42 p. 46, 164, 272, 402, 524; 1995 v. 43 p. 58, 289. (atleast)
[I have misplaced month information.]
"One of the most obvious, pervasive, and troubling problems with
today's students is their fear and loathing of mathematics in any
form, be it simple arithmetic or fairly complicated algebraic
manipulation. This problem has been the subject of much wailing and
gnashing of teeth among geology teachers, but no one has done much of
anything about it. In my opinion one good way to help students
overcome this shortcoming is to include at least some calculation
virtually every day in virtually every aspect of our courses,
including lectures, quizzes, exams, laboratory exercises, discussions,
and so forth.
To assist in the implementation of this approach, this column is being
instituted in JGE. The purposes of the column are to:
 Provide examples of calculations that will help students
appreciate the value of calculation in geology;
 Stress the importance of "order of magnitude" calculation and
develop in students a sense of what is "reasonable";
 Emphasize the idea that calculation should lead to comprehension
in geology, not just the ability to calculate;
 Encourage frequent calculation, so familiarity is increased and
anxiety is diminished; and
 Promote the use of schematics and sketches as aids to calculation.
" [Triplehorn, JGE, 1994,v42,p46]
A probably incomplete list of columns:
 1994 (v42p46) p4647 :
Introduction. "How much further away is the sun than the moon?". "I
recommend Emiliani, 1987, Dictionary of the Physical Sciences
as a basic source.". "The maximum useful range of a radiometric
clock...".
 1994 (v42p164) p164 :
Driving a car through the earth's internal structure.
 1994 (v42p272) p272 :
"Gradients", river slopes.
 1994 (v42p402) p402404 :
Discussion and references to improving geology education. "Would this
make you rich?" exploration of money (6 column inches). "The Law of
Gravity (from Max Brown)".
 1994 (v42p524) p524 :
Scaling.
 1995 (v43p58) p5859 :
"Understanding large numbers".
 1995 (v43p289) p289291 :
"Exponential Growth".