Ebook: 3-D Structural Geology: A Practical Guide to Quantitative Surface and Subsurface Map Interpretation

Geological structures are three dimensional, yet are typically represented by, and - terpreted from, outcrop maps and structure contour maps, both of which are curved two-dimensional surfaces. Maps plus serial sections, called 2½-D, provide a closer approach to three dimensionality. Computer technology now makes it possible for geological interpretations to be developed from the beginning in a fully three dim- sional environment. Fully 3-D geological models allow significantly better interpre- tions and interpretations that are much easier to share with other geologists and with the general public. This book provides an overview of techniques for constructing structural interpretations in 2-D, 2½-D and 3-D environments; for interpolating - tween and extrapolating beyond the control points; and for validating the final int- pretation. The underlying philosophy is that structures are three-dimensional solid bodies and that data from throughout the structure, whether in 2-D or 3-D format, should be integrated into an internally consistent 3-D interpretation. It is assumed that most users of this book will do their work on a computer. C- sequently, the book provides quantitative structural methods and techniques that are designed for use with spreadsheets, mapping software, and three-dimensional c- puter-graphics programs. The book is also intended to provide the background for understanding what interpretive software, for example, a computer contouring p- gram, does automatically. Most techniques are presented in both a traditional format appropriate for paper, pencil, and a pocket calculator, and in quantitative format for use with spreadsheets and computer-graphics or computer-aided-design programs.

This is a handbook of practical techniques for making the best possible interpretation of geological structures at map scale and for extracting the maximum amount of information from surface and subsurface maps. The 3-D structure is defined by internally consistent structure contour maps and cross sections of all horizons and faults.

A CD-ROM supplements the text in several ways. Text figures are reproduced in color and complete Tecplot models are provided for a number of representative figures.

The book is directed toward the professional user concerned about both the accuracy of interpretation and the speed with which it can be obtained from incomplete data. Quantitative methods are emphasized throughout, and numerous analytical solutions are given that can be implemented with a pocket calculator or a spreadsheet.

Interpretation strategies are defined for GIS or CAD users, yet can be done by hand allowing the production of better geological maps and cross sections, and more accurate interpretation.

The reorganized second edition more closely follows the typical interpretation workflow. New material includes examples of 3-D models and technique