The basic purpose of this book is to present an analysis of geo-
logical field techniques which will function as a working guide for
the approach, pursuit, and solution of geological problems, particu-
larly those of mining geology. It is the author's hope that not only
will the book acquaint students with proper field procedures, but
that it also will afford a convenient reference for practicing geol-
ogists. The book has not been written for use by one who is just
beginning his study of geology and engineering, but the presenta-
tion is founded upon the premise that the field man has acquired
the elementary principles of geology and mineralogy.

Geological field work is undertaken primarily to determine the
manner of occurence, the distribution, and the extent of materials
of the earth's crust. In fact, field observation is the foundation
upon which the science of geology is built.

The methods of field geology include treatments of all phases of
the science, and the geologist must be versed in the principles of
mineralogy, petrology, stratigraphy, structural geology, economic
geology, physiography, paleontology, and surveying. The experienced
field man, regardless of any particular specialization, has at least
a basic training in the several geological branches, as all phases
have a certain bearing in use and applicability in the field.

Field work, as practiced at the present time, falls into two gen-
eral classifications: (1) examinations made chiefly to ascertain the
commercial value and/or potential possibilities of a given area;
(2) studies undertaken to describe and delineate rock and mineral
occurrences in general. These classifications exist largely because
analyses of many mineralized areas are made for private enterprise
and the information obtained often is not for public perusal. Con-
versely, when the results of a field study are for public use, or when
the research is chiefly one of a theoretical, academic consideration,
definite economic interpretations rarely are presented.

There is no wish to suggest that techniques for the two types of
field work are at variance, but instead that the objective desired
simply may lead to specialization in certain phases of geology and
related sciences, or to one mode of attack of the particular problem.
Each class of field study has contributed extensively to the develop-

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