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. A large number of exploration geoscientists analyze reflection seismic data to interpret sedimentary sequences and deformation structures to provide prospective leads for exploration in their respective industries. Today, seismic data are used extensively in industries such as hydrocarbon and mineral exploration, carbon dioxide sequestration, sea floor hazard surveys for cables and pipelines and so on. This book primarily deals with reflection seismic data in the hydrocarbon industry.

Interpretation of structures from field is an integral part of structural geology. While research papers cannot display morphologic variations of individual structures, an atlas of field structural snaps remained due. This book fills up that gap. I have drawn most examples from western Himalayan shear zones. The reader is suggested to consult the key papers in the ‘References’ section for more information. I welcome comments and counterarguments at: soumyajitm@gmail.com <...>

COSGROVE, J. W. The role of structural geology in reservoir characterization
ARCHER, J. S. Reservoir characterization and modelling: a framework for field development
FREEMAN, B., YIELDING, G., NEEDHAM, D. T. & BADLEY, M. E. Fault seal prediction: the gouge ratio method
CRAWFORD, B. R. Experimental fault sealing: shear band permeability dependency on cataclastic fault gouge characteristics
GABRIELSEN, R. H., AARLAND, R.-K. & ALSAKER, E. Identification and spatial distribution of fractures in porous, siliciclastic sediments

This guide presents seven itineraries to investigate the geology of the Central Andes, which can be done in seven days of field work along main roads in northern Argentina and Chile. A total of 32 field stops are organized in a complete cross-section that cuts over 600 km of the mountain range, from the Subandean Zone and Eastern Cordillera, between latitudes 24°–23° 20' (Purmamarca–Quebrada de Humahuaca), to the Coastal Cordillera, between latitudes 22° 10'–20° 17' (Tocopilla– Iquique), passing through the domains of North Puna, Western Cordillera, Modern Volcanic Arc, Cordillera de la Sal and Cordillera Domeyko.

The fi eld trip described in this guide starts in the “Norwegian Alps,” the high mountain massif called Jotunheimen, and runs out along Sognefjorden, the world’s longest fjord, to the islands along the west coast of Norway. Geologically, the Sognefjord transect provides a complete cross section through the Caledonian orogenic belt, of Paleozoic age, which in Norway stretches along the west coast from Stavanger to North Cape, a distance of ~2000 km.

It is easier to give examples of geological structures than to define them. The word 'structure' means 'that which is built or constructed'. Structural geologists use the word to signify something that has been produced by deformation; that is, by the action of forces on and within the Earth's crust. Structures consist of a geometric arrangement - of planes, lines, surfaces, rock bodies, etc. The form and orientation of this arrangement reflect the interaction between the deforming forces and the preexisting rock body. <...>

The small-scale structures referred to in this publication are those structures of tectonic origin that can be observed with the naked eye in the field. Their scale varies broadly between that of the hand-specimen to that of the exposure, or even mountainside. Such structures are the visible effects of rock deformation caused by local stresses and movements which have been induced in the rocks by external tectonic forces of possibly unknown origin. Recognition of these minor structures, and appreciation of their origin and significance assist the field geologist to elucidate the larger-scale geological structures of his area.

In 1930 Bruno Sander, in his now classic Gefiigekunde der Gesteine, presented a comprehensive account of the fabric of deformed rocks, new geometric methods for its analysis, and a broad philosophy for its kine¬ matic interpretation. Since then, and especially since the Second World War, Sander’s methods have been applied with varying degrees of success in attempts to elucidate the structure of metamorphic rocks in many countries. Outstandingly successful among such attempts are studies, still in progress, on the nature and geometry of repeated folding in the Highlands of Scotland.