Geological Structures and Maps

Geological Structures and Maps

 GEOLOGICAL maps represent the expression on the earth’s surface of the underlying geological structure. For this reason the ability to correctly interpret the relationships displayed on a geological map relies heavily on a knowledge of the basic principles of structural geology.

This book discusses, from first principles up to and including first-year undergraduate level, the morphology of the most important types of geological structures, and relates them to their manifestation on geological maps. Although the treatment of structures is at an elementary level, care has been taken to define terms rigorously and in a way that is in keeping with current professional usage. All too often concepts such as ‘asymmetrical fold’, ‘fold axis’ and ‘cylindrical fold’ explained in first textbooks have to be re-learned ‘correctly’ at university level. Photographs of structures in the field are included to emphasize the similarities between structures at outcrop scale and on the scale of the map. Ideally, actual fieldwork experience should be gained in parallel with this course.

The book is designed, as far as possible, to be read without tutorial help. Worked examples are given to assist with the solution of the exercises. Emphasis is placed throughout on developing the skill of three-dimensional visualization so important to the geologist.

In the choice of the maps for the exercises, an attempt has been made to steer a middle course between the artificial-looking idealized type of ‘problem map’ and real survey maps. The latter can initially overwhelm the student with the sheer amount of data presented. Many of the exercises are based closely on selected ‘extracts’ from actual maps.