German Title: Strukturelle Entwicklung einer vulkanischen Sequenz des Lahn-Gebietes während der variszischen Orogenese im Rhenoherzynikum (Deutschland)
Preview |
PDF, English
Download (10MB) | Terms of use |
Translation of abstract (English)
Structural analysis has been carried out on a volcanic sequence of Devonian age. The area investigated is situated at Weilburg, a part of the Lahn synclinorium in the Rheinische Schiefergebirge. It was affected by very low- to low-grade metamorphism during the Variscan orogeny. The field structural data analysis: Bedding and s1-cleavage relationships show a clear NW vergence, in which s1-cleavage is steeper. s2-cleavage (s1-cleavage folding) occurs as kinking and buckling. Intersection lineations are dispersed in a form of girdle on stereoplots. Folds plunge to NE as well as to SW. Faults are mostly NW facing boundary thrust and imbricate thrust systems. Superposed folding (basin and dome) structure is constructed on the Lahn syncline. The strain analysis: The 2-D analysis is based on the Rf/f measurement, and 3-D analysis is applied by the direct measurement of the principal finite strain axes. Re-analysis of previous investigations used to interpret a simple shear continental extensional basin model for the Rhenohercynian basin, to be compared with the present Japan Sea and Red Sea. By classifying central, proximal and distal facies in the facies study of volcaniclastic rocks, source areas (volcanic centres) has been used to define the inferred flow directions. Orogenic compression was implied on the study area as a part of continental extension zone during the Variscan orogeny. With it, in the study area full-graben and half-graben basins can be recognized as a full-graben at the Kirschhofen syncline, antithetic half-grabens at the Guntersau-Freienfels and the Freienfels-Ernsthausen sub-areas and synthetic half-grabens at the Ahausen syncline and the Kanapee anticline. The magnetofabric analysis is used to interpret the flow direction of sheet flow lavas which agrees with its inferred flow direction; the current direction of turbiditic lapillituff which is parallel along a half-graben basin, and also, the current direction of epiclastic lapillituff which crosses
Document type: | Dissertation |
---|---|
Supervisor: | Flick, Prof. Dr. Heiner |
Date of thesis defense: | 6 July 2000 |
Date Deposited: | 28 Sep 2000 00:00 |
Date: | 2000 |
Faculties / Institutes: | Fakultät für Chemie und Geowissenschaften > Institut für Geowissenschaften |
DDC-classification: | 550 Earth sciences |
Controlled Keywords: | Tektonik, Strukturgeologie, Variszische orogenese, Rheinisches Schiefergebirge, Weilburg |
Uncontrolled Keywords: | Field geological structures , Strain deformation , AMS (Anisotropy of Magnetic Susceptibility) , Inversion tectonics , Orogenic movement |