Please note that this session was withdrawn and is no longer available in the respective programme. This withdrawal might have been the result of a merge with another session.
GM8.2 | Unravelling landscape responses to tectonic processes over variable spatial and temporal scales
EDI
Unravelling landscape responses to tectonic processes over variable spatial and temporal scales
Convener: Andrea Sembroni | Co-conveners: Dea Brunović, Ettore Valente, Ana Novak, Francesco Pavano
Topography results from the complex interaction of deep-to-shallow Earth forcings and surface processes. These dynamics leave a unique mark on the landscape, spatially quantifiable by combining the classical geomorphological approach (e.g., offset marine and continental landforms, variation in drainage pattern and sinuosity) with numerical modeling of both topography (e.g., slope, local relief, filtered topography), and river network features (e.g., river longitudinal profiles, channel concavity and steepness, -plots). Age modeling of dated offset deposits provides chronological constraints to the spatial distribution of tectonic processes.
Competing relief-building and erosional processes tend to balance out over time, thus, consequently, leading to a modulation of the landscape’s reaction to the changing environmental conditions. These processes act at scales ranging from single fault segments (100-101 km2) to orogen scale (>106 km2), and at time scales typically exceeding those of major climatic cycles (> 105 years).On the other hand, when equilibrium is not yet reached, a landscape is often subjected to one or several dominant topography-modifying processes resulting in the formation of different geomorphic features related to depositional and/or erosional episodes.The geological records resulting from the complex interplay of different forcings often represent a great challenge for interpretation and understanding of the formational processes involved.
However, how fast the landscape reacts to changes in tectonic boundary conditions? What are the topographic metrics,or their combinations, that record tectonic signals with the greatest fidelity?How does the topography change if tectonic forcing is steady over millions of years, or is very abrupt and separated by long intervals of quiescence?Under a regime of persistent tectonic forcing, are there predictable stages of topographic form through which a landscape will evolve?
These are just some of the still open questions whose answers are made difficult by the dynamic and nonlinear nature of the interaction between deep Earth dynamics and Earth surface processes.
Studies that contribute to closing these knowledge gaps are welcomed in this session, especially those carried out by a multidisciplinary approach, combining classical geomorphological analysis of topography, field-based surveys, analogue and numerical experiments, and thermo/geochronological dating techniques.