Page 16 - Statistics and Data Analysis in Geology

Introduction

This book is also designed to aid another type of geologist-in-training-the
student who has taken or is taking courses in statistics and programming. Such
curriculum requirements are now nearly ubiquitous in universities throughout the
world. Unfortunately, these topics are frequently taught by persons who have little
knowledge of geology or any appreciation.for the types of problems faced by Earth
scientists. The relevance of these courses to the geologist’s primary field is often
obscure. A feeling of skepticism may be compounded by the absence of mathemat-
ical applications in geology courses. Many faculty members in the Earth sciences
received their formal education prior to the current emphasis on geomathematical
methodology, and consequently are untrained in the quantitative subjects their stu-
dents are required to master. These teachers may find it difficult to demonstrate
the relevance of mathematical topics. In this book, the student will find not only
generalized developments of computational techniques, but also numerous exam-
ples of their applications in geology and a library of problem sets for the exercises
that are included. Of course, it is my hope that both the student and the instructor
will find something of interest in this book that will help promote the widening
common ground we refer to as geomathematics.

The Book and the Course it Follows

Readers are entitled to know at the onset where a book will lead and how the author
has arranged the journey. Because the author has made certain assumptions about
the background, training, interests, and abilities of the audience, it is also neces-
sary that readers know what is expected of them. This book is about quantitative
methods for the analysis of geologic data-the area of Earth science which some
call geomathematics and others call mathematical geology. Also included is an
introduction to geostatistics, a subspecialty that has grown into an entire branch
of applied statistics.
The orientation of the book is methodological, or “how-to-do-it.” Theory is not
emphasized for several reasons. Most geologists tend to be pragmatists, and are
far more interested in results than in theory. Many useful procedures are ad hoc
and have no adequate theoretical background at present. Methods which are the-
oretically developed often are based on statistical assumptions so restrictive that
the procedures are not strictly valid for geologic data. Although elementary prob-
ability is discussed and many statistical tests described, the detailed development
of statistical and geostatistical theory has been left to others.
Because the most complex analytical procedure is built up of a series of rela-
tively simple mathematical manipulations, our emphasis is on operations. These
operations are most easily expressed in matrix algebra, so we will study this subject,
illustrating the operations with geological examples.
The first edition of this text (published in 1973) devoted a chapter to the FOR-
TRAN computer language and most procedures in that edition were accompanied
by short program listings in FORTRAN. When the second edition appeared in 1986,
FORTRAN no longer dominated scientific programming and computer centers main-
tained extensive libraries of statistical and mathematical routines written in many
computer languages. Large statistical packages implemented almost every proce-
dure described in the text, so program listings were no longer necessary. Now at

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