GM9.2 | Exploring the feedback between tectonics, climate, and surface processes from modelling and quantifying techniques
EDI PICO

Topography is the result of the competition between processes acting at different spatial and temporal scales. Tectonics, climate, and surface processes all leave fingerprints on modern topography, making it difficult for researchers to univocally characterize their contribution to shaping landscapes. Morpho-structural and geomorphic features provide the possibility to quantify the nature and the magnitude of the interaction between tectonics, climate, surface processing, and evolving topography from shorter to longer term timescales.
For instance, hillslope features, bedrock streams, topographic gradients and fluvial dynamics develop into the evolving landscape from the coastal to the high-relief areas. The use of laboratory, numerical and mathematical modelling and the recent advances in geochronological and thermochronological techniques, allow quantitative constraints on the magnitude, rates, and timing of topographic changes.
Moreover, a correct quantification of the interaction between surface processes and endogenous dynamics plays a major role in the evaluation also of geological hazards and related risks. Since the last decades, several techniques have been developed to assess the landscape evolution processes, dealing with analogue numerical models, geodetic tools (GPS and satellite images analysis) and quantifying techniques (cosmogenic nuclides and thermochronometric data). Overall, this data could be crucial when interpreting data coming from field observations.
We invite contributions aiming to link analogue, numerical models, with quantitative techniques, in supporting field interpretations.

Co-organized by SSP2/TS4
Convener: Mauro BonaseraECSECS | Co-conveners: Romano Clementucci, Michele DelchiaroECSECS, Ciro CerroneECSECS, Riccardo Reitano, Laure Guerit, Sebastien Carretier
PICO
| Tue, 25 Apr, 10:45–12:30 (CEST)
 
PICO spot 3a
Tue, 10:45

PICO: Tue, 25 Apr | PICO spot 3a

Chairpersons: Romano Clementucci, Michele Delchiaro, Ciro Cerrone
10:45–10:50
10:50–11:00
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PICO3a.1
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EGU23-5283
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GM9.2
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ECS
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solicited
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On-site presentation
Sebastian G. Wolf, Ritske S. Huismans, Jean Braun, and Xiaoping Yuan

To first order mountain belts grow by crustal thickening and gain their elevated topography through isostatic compensation. High and rising topography in turn modifies the global wind circulation system and is the main locus of (orographic) precipitation. The ensuing flow of water (or ice) redistributes mass through erosion and deposition, counteracts orogenic growth, shapes the appearance of the landscape, and most importantly provides a feedback-loop between surface processes and tectonics. However, it remains debated whether surface processes or lithospheric strength control mountain belt height, width, and longevity, reconciling high erosion rates observed for instance in Taiwan and New Zealand, low erosion rates in the Tibetan and Andean plateaus, and long-term survival of mountain belts for several 100s of million years. Here we use a tight coupling between a landscape evolution model (FastScape) and a thermo-mechanically coupled mantle-scale tectonic model (Fantom) to investigate mountain belt growth. Based on several end-member models and the new non-dimensional Beaumont number, Bm, we provide a quantitative measure of the interaction between surface processes and tectonics, and define three end-member orogen types: Type 1, non-steady state, strength controlled (Bm > 0.5); Type 2, flux steady state, strength controlled (Bm ≈ 0.4−0.5); and Type 3, flux steady state, erosion controlled (Bm < 0.4). Bm can be assessed without complex measurements or assumptions, but simply by knowing a mountain belt’s convergence rate, height, width, first order shortening distribution, and widening rate. In turn, assessing Bm of an orogen provides information about its crustal strength and average fluvial erodibility and gives insight into the factors controlling orogen type: In Himalaya-Tibet , high convergence rates dominate over efficient surface processes (Type 1), in the Central Andes low convergence rates dominate over low fluvial erosional efficiency (Type 1), efficient surface processes balance high convergence rates in Taiwan (likely Type 2), and surface processes dominate in the Southern Alps of New Zealand (Type 3). Our results provide a simple unifying framework quantifying how surface processes and tectonics control the evolution of topography of mountain belts on Earth.

How to cite: Wolf, S. G., Huismans, R. S., Braun, J., and Yuan, X.: The Beaumont number of mountain belts – quantifying the interaction between surface processes and tectonics during orogenesis, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5283, https://doi.org/10.5194/egusphere-egu23-5283, 2023.

11:00–11:02
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PICO3a.2
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EGU23-17444
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GM9.2
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ECS
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On-site presentation
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Ethan Conrad, Riccardo Reitano, and Claudio Faccenna

Many analog transpression studies focus on the structural development of the system without including the effects of surface processes. Considering the high number of transpressional systems globally, the lack of these studies restricts our ability to representatively constrain, interpret, and model the crust and surface through time. Here, we present a new set of analog models to investigate how tectonic and surface processes at transpressive plate boundaries interact to shape topography. Experiments were conducted in a 2 × 1 × 0.5 m plexiglass box, with ends left open for drainage. Inside the box, we fix a plexiglass board cut to 20º obliquity to the sidewall. A mylar sheet is pulled under the board, forming a velocity discontinuity between the fixed board and the moving sheet. We load the board–sheet set up with a ~5 cm thick package of the experimental material (cf. CMII in Reitano et al., 2020, doi: 10.5194/esurf-8-973-2020 at 20 wt. % H20). Surface processes are initiated using commercial misting nozzles aligned with the trend of the wedge. We used a laser scanner to generate digital elevation models incrementally throughout the models and cameras (1 min photo intervals) for particle image velocimetry analysis. Here we focus on three experiments that we conducted using this system across various rainfall and convergence settings. Two tests represent end member CR# (the ratio between convergence and rainfall rate) settings. The third is a dry reference model. By analyzing these models, we attempt to identify the potential feedback between drainage and fault networks to explain morphological differences between experimental wedges with high, low, and no erosion. In all experiments, a bivergent wedge forms, and strain partitioning broadly evolves following previously established models. We find that erosion may influence the structural evolution of transpressional mountain belts leading to accelerated strike-slip partitioning. We also highlight how incision along main structures may localize exhumation in the system. We apply this model to assist in understanding uplift, deformation, and erosion patterns in natural transpressional systems, including the central Transverse Ranges of the San Andreas, the Merida Andes of Venezuela, and the Central-Western Cordillera of Colombia.

How to cite: Conrad, E., Reitano, R., and Faccenna, C.: Erosion-tectonic Sandbox Models of the Structural and Fluvial Evolution of Transpressional Systems, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-17444, https://doi.org/10.5194/egusphere-egu23-17444, 2023.

11:02–11:04
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PICO3a.3
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EGU23-4903
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GM9.2
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ECS
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On-site presentation
Thomas Bernard, Christoph Glotzbach, Daniel Peifer, Al Neely, and Todd Ehlers

The Earth's surface topography reflects the long-term competition between tectonic and climate-driven surface processes. River erosion is a fundamental process that sets the base level for hillslope processes and drives landscape evolution. River profiles reflect external processes, such as tectonic uplift and climate, as well as intrinsic properties of the landscape, such as lithologic variations. River profiles respond to perturbations in these parameters through local changes in channel gradient, which are transmitted upstream of the river channel. River networks affected by these processes may eventually suffer drastic river captures and important drainage reorganization. As a result, river profiles can be used to extract the uplift histories of landscapes. Geochemical data with sensitivities to different time scales, such as thermochronological ages and cosmogenic nuclide concentrations, can be combined in numerical models with river profile analyses to identify governing relationships response for a landscape history. However, the estimation of a complete denudation record through time remains challenging, especially in landscapes where river capture and drainage reorganization have strongly perturbated the river system.

            In this study, we perform inverse modeling of river profiles and thermo- and geochronology data (i.e., low-temperature thermochronology and cosmogenic nuclides) to infer erosive parameters and the topographic history of different settings. The numerical model allows the prediction of river profiles, thermochronological ages (e.g., zircon fission tracks, apatite fission tracks and apatite helium ages), cosmogenic nuclide concentrations, and simplistic river captures. Variability in both rock uplift history and erodibility of different lithologies are accounted for. The model algorithm utilizes an efficient inverse modeling scheme "Simulation-Based Inference" to resolve unknown parameters such as uplift or erodibility of the different lithology. Results are presented from the Neckar catchment located in southwest Germany, which shows evidence for major river captures and drainage reorganization over the last ~10 Ma. Model results allow to reproduce the river profile and thermo-geochronological data of the Neckar catchment for specific uplift and erodibility. Moreover, early experiments indicate a better prediction of the observed data, and therefore, the parameters controlling the erosion rate, when considering river captures.

How to cite: Bernard, T., Glotzbach, C., Peifer, D., Neely, A., and Ehlers, T.: Estimation of erosion rate parameters from neural network inverse modeling of river profile and thermo-geochronology data, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-4903, https://doi.org/10.5194/egusphere-egu23-4903, 2023.

11:04–11:06
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PICO3a.4
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EGU23-5412
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GM9.2
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ECS
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On-site presentation
Victor Buleo Tebar, Mauro Bonasera, Simone Racano, and Giandomenico Fubelli

Drainage network systems are one of the more responsive elements to recent active tectonic from among all the topographic features. Their anomalies can be significant in areas with high relief energy or less noticeable where intense deposition rates might make capable tectonic signatures not visible. In addition, surface processes are even dominated by changes in climate. Since landscape evolution is the result of the combination of these elements, drainage network systems represent a key element for understanding the role and importance of different factors involved in the processes during Quaternary that have led to the formation of the current relief.

The study area comprises two different zones in Piedmont region (North-Western Italy): the Western Po Plain and the Langhe and Monferrato hills, both located in a complex tectonic framework at which a juxtaposition on a crustal scale between Alpine metamorphic Units and the Ligurian Units of the Apennines takes place. A multi-disciplinary approach is proposed combining geomorphology and geostatistics, with the aim of obtaining a better understanding and knowledge of various aspects of the Quaternary evolution of the area on a regional scale.

A morphometric analysis was carried out based on 5 m resolution DEM supported by geological and geomorphological field surveys. To assess the changes in the river network’s direction a quantitative geomorphic analysis of river pattern has been performed through Geographic Information System (GIS) and MATLAB® tools. Different parameters were calculated with the aim of detecting anomalies and the estimation of local uplift and different erosion rates.  Following the extraction of longitudinal river profiles, calculating Normalized Channel steepness index (Ksn) has been possible for assessing river incision, based on local channel slope, contributing drainage area and some other characteristics related to incision processes and basin hydrology. This step has also allowed the identification of knickpoints whose presence represent a deviation of steady-state streams condition and hence a transient phase of potentially landscape changes.  These anomalies are present whether they were produced by tectonic deformation or by different factors. In addition, a paleotopographic reconstructions of Pleistocene deposits have allowed the estimation of the thickness of the deposits and the reconstruction of the river patterns during this period.

Preliminary results have provided relevant evidence of potentially recent and important changes in the regional drainage network of Western Po Plain resulting from the combination of tectonic activity during the Early Pleistocene and the climatic variation from the Middle and Late Pleistocene.

How to cite: Buleo Tebar, V., Bonasera, M., Racano, S., and Fubelli, G.: Assessment of Quaternary variations of the drainage pattern through morphotectonic investigations in Piedmont (North-western Italy), EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5412, https://doi.org/10.5194/egusphere-egu23-5412, 2023.

11:06–11:08
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PICO3a.5
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EGU23-997
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GM9.2
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ECS
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On-site presentation
Anastasiia Derii

The asymmetry of slope of the opposing inclinations of the Eastern Carpathians is a regularity that was recognised over 100 years ago (after Jahn 1992). It is particularly well visible in the Bieszczady Mountains, where the southern slope is steeper than the northern slope and the erosion base of the southern slope is 100 m lower than the erosion base of the northern slope. Previous studies have not exhausted the possibilities of characterising this asymmetry, and contemporary analyses make it possible to refine and verify the theses put forward by previous researchers.  The research is supported by the availability of relatively new sources of data from laser scanning of the Earth's surface, with much greater accuracy than ever before. These data are available for both the N-Polish and S-Slovakian slopes. Their analysis is enabled by modern tools and methods of Geographical Information Systems (GIS). The execution of all measurements and calculations will be automated and much more accurate compared to previous measurements on topographic maps.

The paper will present selected morphometric parameters to determine differences in relief under the influence of asymmetry in the erosion base. The selection of surface units for the analysis of asymmetry will be addressed. Preliminary results of morphometric analysis for mesoregions will be shown: Beskid Niski, Nízke Beskydy, Bieszczady, Poloniny.

How to cite: Derii, A.: Asymmetry of valley systems of the northern and southern slopes of the Flysch Carpathians in the light of geomorphometric analyses, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-997, https://doi.org/10.5194/egusphere-egu23-997, 2023.

11:08–11:10
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PICO3a.6
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EGU23-11834
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GM9.2
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ECS
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On-site presentation
The landscapes of southern Africa: the legacy of mantle dynamic or glacial erosion?
(withdrawn)
Pierre Dietrich, François Guillocheau, Guilhem Douillet, Neil Griffis, Laurie Barrier, Daniel Le Heron, Isabel Montañez, Cécile Robin, Christoph Kettler, and Axel Hofmann
11:10–11:12
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PICO3a.7
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EGU23-13884
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GM9.2
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ECS
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On-site presentation
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Elhanan Harel, Liran Goren, Shelef Eitan, Onn Crouvi, and Hanan Ginat

Valley width is a fundamental morphologic property of rivers that plays a key role in drainage networks' hydrology, ecology, and geomorphology. In many cases, defining and measuring valley width is far from trivial. Therefore, similar to channel width, the valley width (W) is commonly approximated as a power law function of the drainage area (A) and expressed as W = kcAd. Global observations have shown that the exponent  (d) can vary widely but is typically ~0.5. However, in fluvial systems that have undergone drainage reorganization, gradual or abrupt changes in drainage areas along the valley could produce widths that are disproportionate to their drainage areas. As a result, the valley width - drainage area relationship in reorganized systems is expected to differ from undisturbed drainages that have not undergone reorganization.

To test this prediction, we studied 12 valleys in the Negev desert, Israel, and classified them into three categories, based on field evidence and remote sensing data: (i) undisturbed valleys, which are minimally affected by reorganization; (ii) beheaded valleys, whose headwaters were beheaded; and (iii) reversed valleys, which have reversed their flow direction by 180 degrees while exploiting their antecedent valleys. Using a new semi-automatic tool to measure valley width on high-resolution DEMs, we calibrated the best-fit power law for each valley to explore the relationships between drainage area and valley width for each valley category.

Our results show that the valley width-drainage area scaling in reorganized valleys deviated significantly from those in undisturbed valleys in our field area and global observations. The drainage area exponents (d) were lower in beheaded valleys compared to undisturbed valleys but remained positive. In contrast, reversed valleys were characterized by negative d exponents, indicating valley width decrease with increasing drainage area. For the reversed category, we also explored the independent effect of channel slope (S), where the valley width is W = kb AbSc, which resulted in negative and overall similar values of b and c.

In one reversed valley section, we compared the scaling of valley versus channel width as a function of drainage area. We found that in contrast to the downstream narrowing valley, the channel width shows an opposite trend and widens downstream, suggesting that the channel has mostly adjusted to the post-reorganization drainage area distribution. The narrow reversed channel shapes the width of the formative flows, which contrasts significantly with the wide flows of the beheaded valley across the divide. This difference results in a step-change in the unit stream power between the reversed and beheaded channels, potentially leading to a "width feedback" that promotes further divide migration.

Our findings can be used to identify landscapes that have been affected by recent drainage reorganization and should be taken into consideration in studies that use the relationship between valley width and drainage area for valley width predictions, stream power calculations, and landscape evolution models.

How to cite: Harel, E., Goren, L., Eitan, S., Crouvi, O., and Ginat, H.: Drainage reorganization disrupts scaling between drainage area and valley width, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13884, https://doi.org/10.5194/egusphere-egu23-13884, 2023.

11:12–11:14
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PICO3a.8
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EGU23-9778
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GM9.2
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On-site presentation
Audrey Huerta, Ann Blythe, and Paul Winberry

The Transantarctic Mountains (TAM) form a >3000 km-long boundary between East and West Antarctica with extreme relief reaching to >4500 m in elevation. Proximity of the TAM to the Cretaceous/Paleogene West Antarctic Rift System (WARS) suggests a genetic relationship between development of the TAM and extension of West Antarctica. However, the details of this relationship remain elusive.

Here we present the results of a low-temperature thermochronology study in the central TAM combined with numerical modelling of the thermal-kinematic crustal evolution. Sampling was undertaken along the ~100 km long, ~40 km wide Byrd Outlet that cuts through the TAM. We focus on the results of apatite fission track (AFT) analysis of seventeen samples collected along two near-vertical transects. All of these samples yield AFT ages of ~80 Ma. Transect A, located 45 km from the mountain front, has nine ~80 Ma samples along >1500 m of near-vertical relief (580-2140 m asl). Transect B is located 70 km from the mountain front, with eight ~80 Ma old samples along 700 m of near-vertical relief (450 m to 1150 m asl).

These ~identical ages typically would be interpreted to indicate rapid cooling through the AFT partial annealing zone (PAZ; 120°C-60°C). However, inverse modeling (HeFTy) shows that the samples experienced slow cooling (~4°C/m.y.), with samples remaining within the AFT PAZ for 30-60 my. Thus, there appears to be an inherent contradiction between the instantaneous cooling at ~80 Ma and the very slow cooling. 

To explore this apparent contradiction we designed a finite-difference thermal-kinematic model to reconstruct the erosional/cooling history of the crust of the Byrd Outlet region. Successful simulations must predict three things: 1) a coherent 1500 m thick crustal section that passes through the AFT closure temperature (110°C) ± simultaneously (± 5my), 2) this crustal section then must remain in the AFT PAZ for greater than 15 my, and 3) the top of this crustal section is currently located 1300 m below the adjacent surface of the earth (below the current peak of Mt McClintock at 3490 asl).

Modeling results confirm that successful simulations must include rapid incision of a km’s-deep gorge and the associated ± instantaneous cooling of the crustal section, followed by 10’s of millions of years of regional erosion and slow cooling through the AFT PAZ.

These results provide constraints on the timing and mechanisms responsible for the uplift of the central TAM. Firstly, the region-wide 80 Ma ages reveals incision of high topography in the Cretaceous, ~coeval with development of the West Antarctic Rift System. Secondly, this development of high topography far inland from the mountain front is inconsistent with rift-flank uplift. Additionally, the deep incision indicates > 5 km of uplift, which exceeds the amount that could be reasonably assigned to just flexure plus crustal thickening or just flexure plus lithospheric 

How to cite: Huerta, A., Blythe, A., and Winberry, P.: Cretaceous Uplift of the Transantarctic Mountains-Not Due to Rift-Flank Uplift, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-9778, https://doi.org/10.5194/egusphere-egu23-9778, 2023.

11:14–11:16
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PICO3a.9
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EGU23-8566
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GM9.2
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ECS
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On-site presentation
Boulders-induced geomorphic adjustment at a range of spatial scales in experimental landscapes
(withdrawn)
Ron Nativ, Liran Goren, Kobi Habousha, John Laronne, and Jens Turowski
11:16–11:18
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PICO3a.10
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EGU23-69
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GM9.2
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ECS
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Virtual presentation
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Marco Meschis, Gerald Roberts, Jennifer Robertson, Zoe Mildon, Diana Sahy, Rajasmita Goswami, Claudia Sgambato, Joanna Faure Walker, Alessandro Maria Michetti, and Francesco Iezzi

We have mapped and refined the chronology of raised and tectonically deformed Middle-Upper Pleistocene marine terraces in the Messina Strait, southern Italy, within the upper plate affected by crustal extension above the Ionian Subduction Zone. We have mapped up to thirteen palaeoshorelines which identify Middle-Upper Pleistocene sea-level highstands. Our interpretation reveals the chronology and geometry of deformation since ~500 ka for the Reggio Calabria Fault, the Armo Fault and the Messina-Taormina Fault. We show that the spatial patterns of uplift vary both along the strike of these normal faults and through time, and, given the across strike arrangement of the faults, also reveal how the contribution of each fault to the regional strain-rate developed through time. For example, uplift-rates mapped within the footwalls and hangingwalls of the investigated active faults were not constant through the Upper Pleistocene, with a marked change in the location of strain accumulation at ~50 ka. Conversion of uplift rates into fault throw-rates suggests that the three faults has similar throw-rates prior to ~50 ka (in the range 0.77–0.96 mm/yr), with the Armo and Reggio Calabria faults then switching to lower rates (0.32 mm/yr and 0.33 mm/yr respectively), whilst the Messina-Taormina Fault accelerated to 2.34 mm/yr. The rate of regional extension, which has been approximated by summing the implied heave rates across the three faults, was constant through time despite this re-organisation of local strain accumulation at ~50 ka. We explain these out-of-phase fault throw-rate changes during the constant-rate regional extension conditions as due to interactions between these upper plate normal faults. We discuss how fault throw-rates changing through time may affect a long-term seismic hazard assessment within active normal fault systems.

How to cite: Meschis, M., Roberts, G., Robertson, J., Mildon, Z., Sahy, D., Goswami, R., Sgambato, C., Faure Walker, J., Michetti, A. M., and Iezzi, F.: Normal faulting interaction revealed by out-of-phase Quaternary uplift-rate changes implied by studying deformed marine terraces, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-69, https://doi.org/10.5194/egusphere-egu23-69, 2023.

11:18–11:20
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PICO3a.11
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EGU23-5136
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GM9.2
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ECS
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On-site presentation
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Andrea Pezzotta, Alessia Marinoni, Michele Zucali, and Andrea Zerboni

The Al-Hajar Mountains (Northern Sultanate of Oman) characterise the north-eastern part of the Arabian Plate and exhibit a complex tectonic history. They formed during the overthrusting of the Semail Ophiolite and the slope-basin sedimentary sequences over autochthonous sedimentary cover and metamorphic units. The post-orogenic history is characterised by extension and subsequent shortening, forming a series of regional-wide anticlines. The Jebel Akhdar dome, in the central Al-Hajar Mountains, is one of these anticlines; it consists of a pre-Permian basement and Permian to Late Cretaceous carbonate platforms. Along the southern flank of the anticline, the Jebel Akhdar Mesozoic shallow-water limestone is deeply cut into a network of narrow and sometimes meandering canyons. The combination of remote sensing, morphometry, field survey and structural analysis is the multidisciplinary approach used to explore the evolution of canyons and understand the processes that oversaw their deep incision. We identified a group of joint and fault sets, morphostructural lineaments and inactive karst features (both in the epikarst and in the hypokarst) at various scales and evidence for canyons overdeepening respect to the present-day watershed basins. Our reconstruction suggests the ancestral action of karst dissolution along the many structural weaknesses available along the phreatic zone. This led to the formation of a complex network of conduits, later exhumed and occasionally reworked by fluvial processes and linear erosion, whose dynamic was tuned by pre-Quaternary and Quaternary climatic changes.

How to cite: Pezzotta, A., Marinoni, A., Zucali, M., and Zerboni, A.: The interplay between tectonics and karst in the formation of the canyons in the Al-Hajar Mountains (Sultanate of Oman), EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-5136, https://doi.org/10.5194/egusphere-egu23-5136, 2023.

11:20–11:22
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PICO3a.12
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EGU23-2076
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GM9.2
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On-site presentation
Luca Pisano, Francesca Ardizzone, Francesco Bucci, Mauro Cardinali, Federica Fiorucci, Michele Santangelo, and Veronica Zumpano

Lithological and morpho-tectonic settings are among the most important influencing factors in the development of landslide phenomena in terms of size, spatial distribution, and pattern, especially in tectonically active sectors.

In this work, a 1,460 km2 wide portion of SE Apennines, the Daunia Mountains (Apulia region), has been investigated to produce a new geomorphological (historical) landslide inventory map. This area is characterised by low gradients and clay-rich flysch formations (late Cretaceous-Miocene) that have been deformed by contractional tectonics. Daunia Apennines are notoriously prone to landslides, and this new geomorphological historical landslide inventory map reported the presence of 17,437 landslides, with an average density of about 15.6 landslides per square kilometre, excluding lowlands plain. A preliminary analysis conducted for the entire area showed the main relationships between landslides and the different tectonic units. Here, a downscaling investigation is carried out, focusing on an area of approximately 370 km2, where more detailed 1:50,000 geological data are available (Carta Geologica d’Italia, CARG project).

Investigation of landslide size, type and spatial distribution within the different lithologies, shows that smaller landslides tend to develop within the siliciclastic and turbiditic sedimentary succession belonging to the San Bartolomeo Formation. On the other hand, ancient landslides with larger and heterogeneous dimensions, develop in the flysch lithologies made up of reddish thin-bedded clays and silts, interbedded with calcarenites and calcilutites layers, belonging to the Flysch Rosso and Flysch di Faeto Formations. These formations constitute most of the external ridges of the Daunia Apennine, forming the Daunia tectonic unit, which is strongly affected by the Apennine frontal thrusts system.

Similarly to what was observed in other geological settings of the Italian territory, the spatial distribution of landslides appears to be linked to the main morpho-structural lineaments of the region, and especially the spatial pattern of the largest landslides seems both passively and actively controlled by tectonic forcing, which has determined lines of weakness along the slopes. Additionally, the presence of the Apennine frontal thrust also caused topographic growth with increased local relative relief that favoured the occurrence of large landslides.

Building on such analyses, the unprecedented detail of the new geomorphological landslide inventory map, which reports a relative age estimation of landslides, will also help defining a possible landscape evolution pattern starting from evidences of the oldest slope failures that were recognized. Future work will add absolute dating constraints to such evolution pattern hypotheses which will help understand and compare past trend of landslide occurrence to the present day morpho-climatic setting.

How to cite: Pisano, L., Ardizzone, F., Bucci, F., Cardinali, M., Fiorucci, F., Santangelo, M., and Zumpano, V.: Lithological and morpho-structural control on landslide distribution in the Daunia Apennines, Southern Italy., EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-2076, https://doi.org/10.5194/egusphere-egu23-2076, 2023.

11:22–11:24
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PICO3a.13
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EGU23-12227
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GM9.2
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ECS
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Virtual presentation
Geomorphic signatures of the Growing Lesser Himalayan Duplex
(withdrawn)
Sibashish Dash and George Mathew
11:24–11:26
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PICO3a.14
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EGU23-16696
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GM9.2
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ECS
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Virtual presentation
Measuring erosion on uplifting coasts: Shore platform downwearing rates and pattern on inter-tidal rocks at Māhia Peninsula, New Zealand
(withdrawn)
Jokotola Omidiji, Wayne Stephenson, Kevin Norton, and Mark Dickson
11:26–12:30