Geomorphological evidence of tectonic activity of the Marianske Lazne Fault (Czech Republic) and its influence to stream network evolution

Abstract. Alluvial megafans are sensitive recorders of landscape evolution, controlled by autogenic processes and allogenic forcing and influenced by the coupled dynamics of the fan with its mountainous catchment. The Lannemezan megafan in the northern Pyrenean foreland was abandoned by its mountainous feeder stream during the Quaternary and subsequently incised, leaving a flight of alluvial terraces along the stream network. We explore the relative roles of autogenic processes and external forcing in the building, abandonment and incision of a foreland megafan using numerical modelling and compare the results with the inferred evolution of the Lannemezan megafan. Autogenic processes are sufficient to explain the building of a megafan and the long-term entrenchment of its feeding river at time and space scales that match the Lannemezan setting. Climate, through temporal variations in precipitation rate, may have played a role in the episodic pattern of incision at a shorter time-scale. In contrast, base-level changes, tectonic activity in the mountain range or tilting of the foreland through flexural isostatic rebound appear unimportant.

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Numerical modeling of groundwater‐driven stream network evolution in low‐relief post‐glacial landscapes

Earth Surface Processes and Landforms ◽

10.1002/esp.5278 ◽

2021 ◽

Author(s):

Cecilia Cullen ◽

Alison M. Anders ◽

Jingtao Lai ◽

Jennifer L. Druhan

Keyword(s):

Numerical Modeling ◽

Network Evolution ◽

Stream Network

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Autogenic versus allogenic controls on the evolution of a coupled fluvial megafan–mountainous catchment system: numerical modelling and comparison with the Lannemezan megafan system (northern Pyrenees, France)

Earth Surface Dynamics ◽

10.5194/esurf-5-125-2017 ◽

2017 ◽

Vol 5 (1) ◽

pp. 125-143 ◽

Cited By ~ 11

Author(s):

Margaux Mouchené ◽

Peter van der Beek ◽

Sébastien Carretier ◽

Frédéric Mouthereau

Keyword(s):

Numerical Models ◽

Temporal Variations ◽

Tectonic Activity ◽

Mountain Range ◽

Stream Network ◽

Mountainous Catchment ◽

Isostatic Rebound ◽

Base Level ◽

Alluvial Terraces

Abstract. Alluvial megafans are sensitive recorders of landscape evolution, controlled by both autogenic processes and allogenic forcing, and they are influenced by the coupled dynamics of the fan with its mountainous catchment. The Lannemezan megafan in the northern Pyrenean foreland was abandoned by its mountainous feeder stream during the Quaternary and subsequently incised, leaving a flight of alluvial terraces along the stream network. We use numerical models to explore the relative roles of autogenic processes and external forcing in the building, abandonment and incision of a foreland megafan, and we compare the results with the inferred evolution of the Lannemezan megafan. Autogenic processes are sufficient to explain the building of a megafan and the long-term entrenchment of its feeding river on time and space scales that match the Lannemezan setting. Climate, through temporal variations in precipitation rate, may have played a role in the episodic pattern of incision on a shorter timescale. In contrast, base-level changes, tectonic activity in the mountain range or tilting of the foreland through flexural isostatic rebound do not appear to have played a role in the abandonment of the megafan.

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Regional scale analysis of the altimetric stream network evolution

Advances in Geosciences ◽

10.5194/adgeo-7-79-2006 ◽

2006 ◽

Vol 7 ◽

pp. 79-83 ◽

Cited By ~ 1

Author(s):

T. Ghizzoni ◽

M. Lomazzi ◽

G. Roth ◽

R. Rudari

Keyword(s):

Mathematical Model ◽

Carrying Capacity ◽

Regional Scale ◽

Network Evolution ◽

Stream Channels ◽

Stream Network ◽

Sedimentation Stability ◽

Flooding Risk ◽

Sedimentation Processes

Abstract. Floods result from the limited carrying capacity of stream channels when compared to the discharge peak value. The transit of flood waves - with the associated erosion and sedimentation processes - often modifies local stream geometry. In some cases this results in a reduction of the stream carrying capacity, and consequently in an enhancement of the flooding risk. A mathematical model for the prediction of potential altimetric stream network evolution due to erosion and sedimentation processes is here formalized. It works at the regional scale, identifying the tendency of river segments to sedimentation, stability, or erosion. The model builds on geomorphologic concepts, and derives its parameters from extensive surveys. As a case study, tendencies of rivers pertaining to the Valle d'Aosta region are analyzed. Some validation is provided both at regional and local scales of analysis. Local validation is performed both through a mathematical model able to simulate the temporal evolution of the stream profile, and through comparison of the prediction with ante and post-event river surveys, where available. Overall results are strongly encouraging. Possible use of the information derived from the model in the context of flood and landslide hazard mitigation is briefly discussed.

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Investigation of Surface Deformation in Lower Jehlum Valley and Eastern Potwar using SRTM DEM

International Journal of Innovations in Science and Technology ◽

10.33411/ijist/2020020102 ◽

2019 ◽

Author(s):

Asma Ali ◽

Muhammad Usman Tanveer ◽

Rao Kamran Munawar ◽

Saif-ul- Rehman ◽

Iqra Aslam ◽

...

Keyword(s):

Surface Deformation ◽

Active Surface ◽

Tectonic Activity ◽

Drainage Network ◽

Srtm Dem ◽

Surface Geometry ◽

Stream Network ◽

Uplift Rates ◽

Elevation Model ◽

The Impact

This study describes the surface deformation in lower Jehlum and eastern Potwar using remotely sensed Shutter Radar Topographic Mission (SRTM) Digital Elevation Model (DEM) to identify regional uplift rates. Mapping of active surface deformations help to predict seismic hazards. DEMs are the fundamental input factors that identify the surface geometry and its belongings. These belongings include stream offset, elevation, and slope breaks within a contributing area. This study provides an evidence of tectonic activity and its impact on regional drainage network using SRTM DEM. Various indices including concavity and steepness were computed using power law in steady state conditions. We prepared the drainage network map of the study site showing uplift rates in mm/year. The deflection in stream network proves the existence of active fault in this region which controls the local drainage network. The results prove the relative uplift along Main Boundary Thurst (MBT) and the impact of active tectonic on evolving young organs.

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The pecularities of shear crack pre-rupture evolution and distribution of seismicity before strong earthquakes

Natural Hazards and Earth System Science ◽

10.5194/nhess-1-145-2001 ◽

2001 ◽

Vol 1 (3) ◽

pp. 145-158 ◽

Cited By ~ 1

Author(s):

D. Kiyashchenko ◽

V. Troyan

Keyword(s):

Fractal Dimension ◽

Shear Crack ◽

Cluster Formation ◽

Network Evolution ◽

Tectonic Activity ◽

Crack Network ◽

Strong Earthquakes ◽

Elastic Bodies ◽

Future Earthquake ◽

External Stresses

Abstract. Several methods are presently suggested for investigating pre-earthquake evolution of the regions of high tectonic activity based on analysis of the seismicity spatial distribution. Some precursor signatures are detected before strong earthquakes: decrease in fractal dimension of the continuum of earthquake epicenters, cluster formation, concentration of seismic events near one of the nodal planes of the future earthquake, and others. In the present paper, it is shown that such peculiarities are typical of the evolution of the shear crack network under external stresses in elastic bodies with inhomogeneous distribution of strength. The results of computer modeling of crack network evolution are presented. It is shown that variations of the fractal dimension of the earthquake epicenters’ continuum and other precursor signatures contain information about the evolution of the destruction process towards the main rupture.

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