P.A. Ziegler, 1983. "Inverted Basins in the Alpine Foreland", Seismic Expression of Structural Styles: A Picture and Work Atlas. Volume 1–The Layered Earth, Volume 2–Tectonics Of Extensional Provinces, & Volume 3–Tectonics Of Compressional Provinces, A. W. Bally
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Sedimentary basins may be created by lateral divergent motions of crustal elements in the sense of plate tectonics or intraplate tectonics. Plates moving apart generate space for troughs between their margins. The troughs are filled with sediments which have been eroded at the plate edges. The depths of these depressions depend on the amount of divergence of the plates and the thickness of the crust beneath.
Convergent plate motions create compressional deformations within the plates and at their boundaries. They can result in the inversion of former sedimentary basins accompanied by structures which are typical for the occurrence of lateral compressive plate motions - anticlines, partly eroded and truncated overthrusts, reverse faults, and convergent wrench faults. Erosion processes are active simultaneously with the uplift of the anticlines, and cause secondary basins between the anticlines to be filled with sediments.
The structural style of inverted basins in the Alpine foreland of Europe is illustrated on the basis of five examples, the locations of which are given on the tectonic sketchmap: 1) Bristol Channel trough; 2) Sole Pit basin; 3) Broad Fourteens basin; 4) Western Lower Saxony basin; and the 5) Ronne Graben.
These basins developed during the Triassic to Early Cretaceous under a tensional regime and formed part of the complex Mesozoic rift system of western and central Europe. Grabens and wrench-induced troughs located in the northern Alpine foreland (for example, Sole Pit, Broad Fourteens basins, Emsland area, Ronne Graben) became inverted during the late Senonian and Paleocene. At the same time the Rhenish and particularly the Bohemian massifs became transsected by wrench and steep reverse faults along which major basement blocks were uptilted. Grabens located in the northwestern Alpine foreland were inverted during the Oligocene and Miocene.
Timing of the compressional and wrench deformation in the Alpine foreland can be related to major orogenic events in the Alpine foldbelt. They are therefore thought to be the result of compressive stresses that were transmitted into the Alpine foreland plate during the Alpine diastrophism. This would require, on one hand, a certain amount of coupling between the foreland and the Alpine foldbelt at the Alpine A-subduction zone, and, on the other hand, within the foreland itself, a decoupling between the crest and the mantle and/or decoupling within the crust.
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Seismic Expression of Structural Styles: A Picture and Work Atlas. Volume 1–The Layered Earth, Volume 2–Tectonics Of Extensional Provinces, & Volume 3–Tectonics Of Compressional Provinces
Until a few decades ago, structural and regional geology were traditionally the preserve of field geologists. They usually mapped areas of outcropping deformed rocks and supplemented their work by laboratory studies of rock deformation and by theoretical work. Structural geology became tied to the geology of uplifts, folded belts, and underground mines, all of which were accessible to direct observation. Since World War II we have witnessed a tremendous development of geophysics in oceanography and in petroleum geology. Academic geophysicists in oceanography led their geological colleagues into modern plate tectonics and industry geophysicists developed reflection seismology into a superb structural mapping tool that penetrated the subsurface.
Today we are facing a situation where instruction and textbooks in structural geology are almost entirely dedicated to rock deformation, analytical techniques in detailed field geology and summaries of plate tectonics. Illustrations based on reflection seismic profiles are virtually absent in textbooks of structural geology. These texts illustrate only the parts of the proverbial elephant, together with some conjecture, but without ever offering a glimpse of the whole elephant.
Some of the reason cited for the relative scarcity of published reflection profiles are: 1) the confidentiality of exploration data; 2) difficulties in the photographic reduction and reproduction of seismic profiles for a book format; 3) the two-dimensional nature of vertical reflection profiles; and 4) the obvious distortions in reflection profiles that are typically recorded in time.
The AAPG leadership felt that it was time to attempt to correct the situation and to produce this picture and work atlas. The first volumes, of what may become a series of volumes, are addressing an audience that includes: petroleum geologists concerned with structural interpretations; exploration companies that provide in-house training; the AAPG continuing education program; and academic colleagues interested in updating their curricula in structural geology by inclusion of reflection profiles from the “real world” in their teaching.
The atlas is not meant to be a textbook in reflection seismology (instead we listed some at the end of this introduction) nor a text in structural and/or regional geology. Our intent is simply to provide a teaching tool.