Open AccessContinental collisions and seismic signature
Author(s) -
Meissner R.,
Wever Th.,
Sadowiak P.
Publication year - 1991
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.1991.tb03440.x
Subject(s) - geology , crust , collision , seismology , thickening , continental crust , upper crust , continental collision , erosion , geophysics , reflection (computer programming) , tectonics , paleontology , subduction , chemistry , computer security , polymer science , computer science , programming language
SUMMARY Reflection seismics; in compressional belts has revealed the structure of crustal shortening and thickening processes, showing complex patterns of indentation and interfingering of colliding crusts and subcrustal lithospheres. Generally in the upper crust large zones of detachments develop, often showing duplexes and ‘crocodile’ structures. The lower crust from zones of active collision (e.g. Alps, Pyrenees) is characterized by strongly dipping reflections. The base of the crust with the Moho must be continuously equilibrating after orogenic collapse as areas of former continental collision exhibit flat Mohos and subhorizontal reflections. The depth to the Moho increases during collision and decreases after the onset of post‐orogenic extension, until finally the crustal root disappears completely together with the erosion of the mountains. Processes, active during continental collisions and orogenic collapse, create distinct structures which are imaged by reflection seismic profiling. Examples are shown and discussed.