Structural concepts and techniques. Basic concepts, folding and structural techniques / Структурные концепции и методы. Основные понятия, приемы складывания и структурирования

Broadly interrelated assemblages of geologic structures constitute the fundamental structural styles of petroleum provinces. These assemblages generally are repeated in regions of similar deformation, and their associated hydrocarbon traps can be anticipated prior to exploration. Styles are differentiated on the basis of basement involvement or detachment of sedimentary cover. Basement-involved styles include wrench-fault structural assemblages, compressive fault blocks and basement thrusts, extensional fault blocks, and warps. Detached styles are decollement thrust-fold assemblages, detached normal faults (‘growth faults’’ and others), salt structures, and shale structures.

These basic styles are related to the larger kinematics of plate tectonics and, in some situations, to particular depositional histories. Most styles have preferred plate-tectonic habitats: (1) wrench faults at transform and convergent plate boundaries; (2) compressive fault blocks and basement thrusts at convergent boundaries, particularly in forelands and orogenic belts; (3) extensional fault blocks at divergent boundaries in all stages of completion and certain parts of convergent boundaries; (4) basement warps in a variety of plate-interior and boundary settings; (5) decollement thrust-fold belts in trench inner walls and foreland zones of convergent boundaries; (6) detached normal faults, usually in unstable, thick clastic wedges (mostly deltas); (7) salt structures primarily in interior grabens that may evolve to completed divergent boundaries; and (8) shale structures in regions with thick overpressured shale sequences. <...>