Czerwony spągowiec Europy Środkowej; uwarunkowanie rozwoju basenu przez tektonikę płyt

E. Craig Jowett



The Rotliegendes, Basin and Range and Alpine foreland rift basins all demonstrate rapid subsidence in one or more narrow linear basins in an extensional tectonic environment, and an evolution from a sedimentary pattern of coarse transverse alluvial fan-transverse braided river plain-saline lake facies to one of finer grained transverse alluvial fan-braided/sinuous river plain-longitudinal meandering trunk river (+ /- saline lake) facies. This produces a distinctive rift basin architecture of long and narrow, but thick, belts of facies banked up against both faultbounded edges of the linear basins.
Foreland molasse wedge basins were formed just prior to the rifts during the respective Hercynian, Cordilleran and Alpine orogenies, and demonstrate a rapid but regional subsidence over an extensive area in a compressional tectonic environment. They show a cyclic evolution of patterns from finer grained transverse alluvial fan-transverse high sinuosity river coastal plain-transverse deltaic/shallow marine clastic facies deposited during quieter times, to coarser transverse alluvial fan-transverse high sinuosity river/coal swamp-longitudinal meandering trunk river facies formed during thrusting. The resulting architecture is an extensive wedge of sediments thickest near the thrust front and thinning onto the continent, with the facies forming much wider belts than in the foreland rift basins.
These two basin types occur in the same foreland location with similar source regions, have broadly similar structurally-controlled sedimentation and facies, and are fairly close in time. However, the states of stress which formed the basinal structures were very different extensional versus compressional), and as a result of this alone, the evolution of sedimentation patterns and the final basin architecture were markedly different. Because the state of stress of a tectonic province at any given time is controlled by plate tectonic interactions, it is evident that the foreland basin type and basin architecture such as the Rotliegendes basins are governed directly and solely by plate tectonic processes.

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