Structural geology deals with the deformation of rocks. After their formation, sedimentary and igneous rocks may remain undisturbed or are deformed to different degrees. A volume of rock may change shape, rotate bodily, fracture or be displaced from one place to another. Such changes may be visible to us, for example, by the tilting of horizontal strata, by development of folds in originally planar beds, by distortion of pebbles, fossils and mineral grains in rocks and by the fragmented character of an originally continuous bed. If these features are in a large scale, their three-dimensional forms are not visible to us; they can be studied only on the eroded surface of the earth. One of the primary objectives of structural geology is to determine three-dimensional forms of these structures mainly from observations on the surface. The first step of structural analysis of an area is to study the geometry of the structures, i.e. to study their morphology and orientation (or attitude), both by direct observation of small structures in the outcrop and by reconstruction of large structures <...>

This chapter is concerned with the orientations of lines and planes. The structural elements that we measure in the field are mostly lines and planes, and manipulating these elements on paper or on a computer screen helps us visualize and analyze geologic structures in three dimensions. In this chapter we will examine several graphical and mathematical techniques for solving apparent-dip problems. Each technique is appropriate in certain circumstances. The examination of various approaches to solving such problems serves as a good introduction to the techniques of solving structural problems in general. Finally, many of these problems are designed to help you visualize structural relations in three dimensions, a critical skill for the structural geologist. <...>

This part of the book introduces the fundamental tools of structural geology. The first four chapters are designed to accustom students to visualizing the attitude, location, and dimensions of geologic structures. (Appendix 1 outlines elementary aspects of maps and cross sections and thus provides an optional introduction to these chapters). We discuss how to measure and describe lines and planes, how to use a compass, how to create and interpret contour maps, how to cakulate the attitude of planes from point data, and how to calculate the thickness and depth of layers.

Analyses of geological structures from field exposure of rocks have been one of the important and intriguing disciplines in (applied) Earth Sciences. Since the 1990s, especially after the boom of three‐dimensional seismic technologies, reflection seismic data in two and three dimensions have become the modern ‘field’ for geologists.

Публикуемая работа В.В.Бронгулеева «Мелкая складчатость платформы» представляет большой интерес как оригинальное исследование своеобразных тектонических проявлений на Русской платформе. Достаточно полная и обстоятельная сводка по вопросам распространения и морфологии малых складок, до последнего времени весьма слабо изученных, и критика разнообразных гипотез их возникновения представляют существенную и наиболее ценную часть этого труда.

В работе рассматривается происхождение складчатости на при-мерах строения древних и молодых платформ, краевых прогибов и геосинклинальных областей. Доказывается, что все пликативные дислокации образовались в аллохтонных пластинах в результате горизонтального сжатия, которое испытывали слоистые комплексы пород.
Работа является теоретическим исследованием, имеющим важное практическое значение. Установленные, в ней закономерности формирования складок позволяют существенно повысить эффективность поисково-разведочных работ на нефть, газ, руды и другие полезные ископаемые

Fundamentals of Structural Geology provides a new framework for the investigation of geological structures by integrating field mapping and mechanical analysis. It emphasizes the observational data, modern mapping technology, principles of continuum mechanics, and the mathematical and computational skills, necessary to map, describe, model, and explain deformation in the Earth’s lithosphere quantitatively.

We begin our study of deformation in the earth from a global, even planetary, perspective by describing the major structural features of the earth’s surface and by identifying the large-scale situations and processes by which the upper layers of the eai th undergo vertical and horizontal displacement. Beginning with Chapter 2 our emphasis changes from the major settings of global deformation to individual structures, classes of structures, and their mechanisms of formation.

After a general introduction to folding this session considers what special terms are required to describe the geometric features of folds: first those terms necessary to define features of a single folded surface, then those which describe the geometric relationships of adjacent folded layers. Special techniques to describe curvature variations based on harmonic—or Fourier—analyses are recommended and it is shown how this type of analysis is practical both for general descriptive purposes as well as for very exact analysis. The relationships of small wavelength folds in polyharmonic folds are described and practical ways of recording changing fold symmetry discussed.

General Statement. The aim of this book is to discuss the processes that operate during the deformation and metamorphismof rocks in the crust and upper lithosphere of the Earth with the goal of understanding how these processes control or influence the structures that we observe in the field.