This study was carried out in the framework of a project sponsored by the Hungarian National Science Foundation (OTKA NK83400) and TÁMOP-4.2.2/B-10/1-2010-0030 Pleistocene alteration of drainage network and diverse surface morphology forced by basement structure in the foreland of the Eastern Alps G. Kovács T. Telbisz Department of Geophysics and Space Sciences Department of Physical Geography Eötvös Loránd University, Budapest Institute of Photogrammetry and Remote Sensing Vienna University of Technology, Vienna European Geosciences Union General Assembly 2012 24 th April 2012
Study area Vienna A U S T R I A Eastern Alps + Styrian Basin 24th April 2012 Little Hungarian Plain _ Budapest H U N G A R Y EGU General Assembly 2012 2/20
3/20 Study area: geology Bernstein Mts. Miocene sediment, partly covered by loess Outcropped uplifting metamorphic units on surface Different aged Pleistocene gravel terraces
4/20 Study area: Miocene dynamics Bernstein Mts. Study area Study area Kinematic model of lateral extrusion in the Eastern Alps (Ratschbacher et al. 1991) Exhumation of Rechnitz Window (Dunkl et al. 1998)
5/20 Study area: recent dynamics Bernstein Mts. + - Study area Study area Vertical motions by Joó et al. 1992 Generalised stress and strain pattern by Bada et al. 2007
6/20 Study area: surface morphology Bernstein Mountains Hilly character since Upper Pannonian W _ E E: - steep scarps - slightly tilted blocks W: - steep scarps - highly eroded area
7/20 Study area: drainage network Bernstein Mountains Hilly character since Upper Pannonian E: - steep scarps - slightly tilted blocks W: - steep scarps - highly eroded area Systematic drainage network - bends - also on plains
8/20 Study area: general surface structure Slightly tilted block character? otherwise remnant ridges? - Straights can be fitted to ridges - Incised streams - Steep scarps 1 2 1 2 4 3 3 5 4 5
9/20 Study area: general surface structure Kőszeg-Rechnitz Mts. C A B
10/20 Study area: general surface structure model - Slightly tilted units bordered by steep scarps - subsiding/uplifting units contradictory theories: - tectonic origin - formed by former rivers Recent stress field (Bada et al.)
11/20 Aims - Slightly tilted units bordered by steep scarps - subsiding/uplifting units contradictory theories: - tectonic origin - formed by former rivers 1.evidences to tectonic forces - terrace levels - lignite layers 2.connection to the deeper structure - faults - tilted paleosurfaces
12/20 Lignite layers + field observations fault series + abandoned mine: 0.5-6 m throw 1-5 m folds Smaller then the scarp Tilting border 1 2 1 2
13/20 Gravel terraces, theory Systematic changing Tilting or incision? Further details of drainage reorganization are provided on EGU2012-403, today at board A443
Gravel terraces Different W E tilting, dissected terrace 24 th April 2012 EGU General Assembly 2012 14/20
Gravel terraces Different N S tilting 24 th April 2012 EGU General Assembly 2012 15/20
Connection to the basement 24 th April 2012 EGU General Assembly 2012 1 basement fault; 2 basement contour; 3 scarp connected with fault; 4 scarp not connected with scarp; 5 observed tilting 16/20
Conclusion Results proved: - continuous tilting - normal faulting - connection to the deeper structure - BUT: eroded scarps Further issues: - tectonics/compaction/erosion? 24 th April 2012 EGU General Assembly 2012 1 basement fault; 2 basement contour; 3 scarp connected with fault; 4 scarp not connected with scarp; 5 observed tilting 17/20
Conclusion Results proved: - continuous tilting - normal faulting - connection to the deeper structure - BUT: eroded scarps Further issues: - tectonics/compaction/erosion? Dombrádi et al. 2010 Horváth et al. 2012 EGU2012-10178 24 th April 2012 EGU General Assembly 2012 1 basement fault; 2 basement contour; 3 scarp connected with fault; 4 scarp not connected with scarp; 5 observed tilting 18/20
Conclusion Results proved: - continuous tilting - normal faulting - connection to the deeper structure - BUT: eroded scarps Further issues: - tectonics/compaction/erosion? Dombrádi et al. 2010 24 th April 2012 EGU General Assembly 2012 1 basement fault; 2 basement contour; 3 scarp connected with fault; 4 scarp not connected with scarp; 5 observed tilting 19/20
Conclusion Results proved: - continuous tilting - normal faulting - connection to the deeper structure - BUT: eroded scarps Further issues: - tectonics/compaction/erosion? Thank you for your attention! This study was carried out in the framework of a project sponsored by the Hungarian National Science Foundation (OTKA NK83400) and TÁMOP-4.2.2/B-10/1-2010-0030 Further details of drainage reorganization are provided on EGU2012-403, today at board A443 s_kovacs_gabor@hotmail.com 24 th April 2012 EGU General Assembly 2012 1 basement fault; 2 basement contour; 3 scarp connected with fault; 4 scarp not connected with scarp; 5 observed tilting 20/20