Martine Simoes

• PhD
• Researcher at Paris Institute of Earth Physics

Asymmetric morphologies are ubiquitous in many landscapes, but the influence of tectonics, climate or bedrock properties on the development and persistence of this asymmetry is difficult to assess.This study investigates the implications of structurally-controlled relief asymmetry on drainage divide dynamics and network organization.We focus on the...

The Tibetan Plateau stands as a prominent topographic feature at the Earth's surface, characterized by intense seismic activity, in particular along its bounding mountain ranges. To the northwest, the Western Kunlun Range has received increasing attention since the 2015 Pishan earthquake but its kinematics of deformation remain to be properly docum...

Along convergent boundaries, the role played by mantle drag remains poorly understood despite its potential impact on subduction dynamics and in turn on the deformation regime of the overriding plate. In this study, we present 11 three‐dimensional analog models of subduction including an overriding plate, in which mantle drag at the base of the low...

The mechanisms controlling mountain building at subduction zones remain debated. In particular the interaction between mantle flow and subduction has been poorly addressed while fundamental in controlling plate displacement and deformation. Here, we conduct three-dimensional analogue models at the scale of the upper mantle adding a horizontal mantl...

Active faults accommodate tectonic plate motion through different slip modes, some stable and aseismic, others characterized by the occurrence of large earthquakes after long periods of inactivity. Although the slip mode estimation is of primary importance to improve seismic hazard assessment, this parameter inferred today from geodetic observation...

Active faults accommodate tectonic plate motion through different slip modes, some stable and aseismic, others characterized by the occurrence of large earthquakes after long periods of inactivity. Although the slip mode estimation is of primary importance to improve seismic hazard assessment, this parameter inferred today from geodetic observation...

The Andes are an emblematic active Cordilleran orogen. Mountain building in the Central Andes (∼20∘ S) started by the Late Cretaceous to early Cenozoic along the subduction margin and propagated eastward. In general, the structures sustaining the uplift of the western flank of the Andes are dismissed, and their contribution to mountain building rem...

The Andes are an emblematic active Cordilleran orogen. Mountain-building in the Central Andes (~20° S) started by Late Cretaceous to Early Cenozoic along the subduction margin, and propagated eastward. In general, the structures sustaining the uplift of the western flank of the Andes are dismissed, and their contribution to mountain-building remain...

Kinematic constraints on the Cenozoic deformation along the northwestern edge of the Tibetan Plateau remain limited. Combining surface geological data and seismic profiles, we document the structural geometry and kinematics of the large‐scale east‐west striking Hotan anticline, along the foothills of the Western Kunlun Range. Four new balanced cros...

The Andes are an emblematic active Cordilleran orogen. It is admitted that mountain-building in the Central Andes at ~20°S started by Late Cretaceous to Early Cenozoic along the subduction margin, and propagated eastward. In general, the structures sustaining the uplift of the West Andean flank are dismissed, and their contribution to mountain-buil...

The quantification of active tectonics from geomorphological and morphometric approaches commonly implies that erosion and tectonics have reached a certain balance. Such equilibrium conditions are however rare in nature, as questioned and documented by recent theoretical studies indicating that drainage basins may be perpetually re-arranging even t...

The quantification of active tectonics from geomorphological and morphometric approaches most often implies that erosion and tectonics have reached a certain balance. Such equilibrium conditions may however be seldom found in nature, as questioned and documented by recent theoretical studies, in particular because drainage basins may be quite dynam...

Tectonics and climate-driven surface processes govern the evolution of Earth’s surface topography. Topographic change in turn influences lithospheric deformation, but the elementary scale at which this feedback can be effective is unclear. Here we show that it operates in a single weather-driven erosion event. In 2009, typhoon Morakot delivered ~ 3...

Topography in forearc regions reflects tectonic processes along the subduction interface, from seismic cycle-related transients to long-term competition between accretion and ero- sion. Yet, no consensus exists about the topography drivers, especially as the contribution of deep accretion remains poorly constrained. Here, we use thermo-mechanical s...

Basin-averaged denudation rates may locally exhibit a wide dispersion, even in areas where the topographic steady state is supposedly achieved regionally. This dispersion is often attributed to the accuracy of the data or to some degree of natural variability of local erosion rates which can be related to stochastic processes such as landsliding. A...

Fig. 8. Details of the regional balanced geological transects across the southern part of the Tarim Basin and the Western Kunlun and Altyn Tagh ranges (see Fig. 7 for location and Fig. 6 for abbreviation labels).

Fig. 10. Details of the regional balanced geological transects across the northern part of the Tarim Basin and the Southern Tian Shan Range (see Fig. 7 for location and Fig. 6 for abbreviation labels).

Fig. 9. Details of the regional balanced geological transect B across the central part of the Tarim Basin (see Fig. 7 for location and Fig. 6 for abbreviation labels).

Fig. S2. Examples of seismic profiles and interpretations used to construct the regional balanced geological transects presented in Fig. 7, Fig. 8, Fig. 9, Fig. 10, and Fig. S3 (see Fig. 6 for abbreviation labels). The location of these profiles is given in the top map insert (same legend as in Fig. 1).

Fig. 3. Velocity functions used for time-to-depth conversion of the seismic interpretations. For each sediment package (Sinian-Paleozoic, Permian-Mesozoic and Cenozoic), these velocity functions are composed of two parts: (1) an upper part (solid line) corresponding to a single linear regression of the vertical seismic profiles of P-wave data (brow...

Fig. 5. Example of surface data and the associated detailed work on the eastern part of the Mazar Tagh emergent thrust ramps and deep fault system (see Fig. 1 for location). (A) Satellite image (Landsat images with a 28-m resolution) of the Mazar Tagh ridge. (B) Geological and structural map of the same area constructed from field data, satellite i...

Fig. 12. Components for the crustal-scale cross-sections presented in Figs. 13 and S4 (see Fig. 6 for abbreviation labels). (A) Example of an elevation profile extracted from the SRTM3 DEM and averaged every 50 km in the range (green dashed line). This average topography corresponds to the main input for assessing the Moho depth below the ranges by...

Fig. S3. Regional balanced geological transects across the Tarim Basin and surrounding ranges at a scale of 1:2,000,000 (see Fig. 6 for location and abbreviation labels). The main data used to construct these cross-sections are specified above each transect. References are listed in Supplementary information S1.

Fig. S4. Simplified crustal-scale cross-sections used to assess the shortening accommodated across the ranges surrounding the Tarim Basin from crustal budgets (see Fig. 12 and Supplementary information S2 for methodology). Green solid lines in the top-centre map insert (same legend as in Fig. 11) locate these cross-sections, green dashed lines in b...

Fig. 2. Simplified chronostratigraphic chart of the Tarim Basin, Western Kunlun Range and Southern Tian Shan. Black arrows represent the main decollement levels in the Tarim area, while colour lines correspond to the seismic horizons picked for this study.

Fig. 4. Example of surface data and the associated detailed work on the Qimugen fold-thrust system (see Fig. 1 for location). (A) Satellite image (Landsat images with a 28-m resolution) of the Qimugen hills. (B) Geological and structural map of the same area constructed from field data, satellite images and seismic profiles. (C) Field picture of th...

Georeferenced structural map of the Cenozoic deformation in the Tarim area (kmz format). Yellow: Cenozoic cover structures. Orange: Paleo-Mesozoic cover structures. Red: Basement structures. ➢ We want to caution users of these data that this map is drawn at a regional-scale with certain structures being localised within a few kilometres of accura...

Fig. 6. Structural map of the Cenozoic deformation of the Tarim Basin and surrounding ranges. Simplified and abbreviated structure labels are spelled out in the upper right cartoon. (A) Structures outcropping at the surface only. (B) Structures outcropping at the surface and hidden below the Cenozoic sediments of the Tarim Basin. Structures rooted...

Fig. 1. Geographical and geological setting of the Tarim area and location of the data used in this study. Only the main structures outcropping at the surface are represented. References for the data from previous studies are indicated below the map. Green long-dashed lines locate the regional balanced geological transects A, B, C and D presented i...

Fig. 11. Tectonic map of the Cenozoic deformation of the Tarim Basin and surrounding ranges. Structures rooted in the basement are represented in red, while structures rooted into a sedimentary decollement are displayed in orange (for structures developed above a Paleozoic decollement) or in yellow (for structures developed above a Cenozoic decolle...

Fig. 13. Possible synthetic crustal-scale cross-sections across the Tarim Basin, Western Kunlun Range and Southern Tian Shan (see Fig. 6 for location and ab- breviation labels). (A) and (B) Cross-sections with the basement-cored uplifts in the basin rooted into a crustal decollement (in the middle or at the base of the crust, respectively). These i...

With its central position between the Tibetan Plateau and the Tian Shan Range, the Tarim Basin is a key element of the Cenozoic Asian orogenic system. However, a comprehensive regional study, and more particularly the quantification of shortening through this basin and its margins, are still needed to understand its role in the Cenozoic deformation...

Basin-averaged denudation rates may locally exhibit a wide dispersion, even in areas where the topographic steady state is supposedly achieved regionally. This dispersion is often attributed to the accuracy of the data or to some degree of natural variability of the signal, but it can also be attributed to stochastic processes such as landsliding....

The Andes are the modern active example of a Cordilleran-type orogen, with mountain-building and crustal thickening within the upper plate of a subduction zone. Despite numerous studies of this emblematic mountain range, several primary traits of this orogeny remain unresolved or poorly documented. The onset of uplift and deformation of the Frontal...

The Andes are the modern active example of a subduction-type orogen, with mountain-building and crustal thickening within the upper plate of a subduction zone. Despite numerous studies of this emblematic mountain range, several primary traits of this orogeny remain unresolved or poorly documented. The onset of uplift and deformation of the Frontal...

Study of now-exhumed ancient subduction zones has evidenced km-scale tectonic units of marine sediments and oceanic crust that have been tectonically underplated (i.e. basally accreted) to the overriding plate at more than 20-km depth. However, the rare examples of such a huge mass transfer in active subduction zones (e.g. SW-Japan, New-Zealand, Ch...

West-verging thrusts, synthetic with the Nazca - South America subduction interface, have been recently discovered at the western front of the Andes. At ~33°30’S, the active San Ramón fault stands as the most frontal of these west-verging structures, and represents a major earthquake threat for Santiago, capital city of Chile. Here we elaborate a d...

The Andean belt is the only present-day active case example of a subduction-type orogeny. However, an existing controversy opposes classical views of Andean growth as an east-verging retro-wedge, against a recently proposed bi-vergent model involving a primary west-vergent crustal-scale thrust synthetic to the subduction. We examine these diverging...

The Andean belt is the only present-day active case example of a subduction-type orogeny. However, an existing controversy opposes classical views of Andean growth as an east-verging retro-wedge, against a recently proposed bi-vergent model involving a primary west-vergent crustal-scale thrust synthetic to the subduction. We examine these diverging...

Study of now-exhumed ancient subduction systems have evidenced km-scale tectonic units of marine sediments and oceanic crust that have been tectonically underplated (i.e. basally accreted) from the downgoing plate to the overriding plate at more than 30-km depth. Such huge mass transfers must have a major impact, both in term of long-term topograph...

The Western Kunlun mountain range is a slowly converging intra-continental orogen where deformation rates are too low to be properly quantified from geodetic techniques. This region has recorded little seismicity, but the recent July 2015 (Mw 6.4) Pishan earthquake shows that this mountain range remains seismic. To quantify the rate of active defor...

West-verging thrusts, synthetic with the Nazca - South America subduction interface, have been recently discovered at the western front of the Andes. At ~33°30’S, the active San Ramón fault stands as the most frontal of these west-verging structures, and represents a major earthquake threat for Santiago, capital city of Chile. Here we elaborate a d...

The Andes, one of the most significant reliefs on Earth, is the case example of a subduction-type mountain belt. In central Chile and western Argentina, the particular east-vergent structure of the Aconcagua fold-and-thrust belt (AFTB) is found atop a huge basement high with elevations > 4000 m, the Frontal Cordillera. Classical conceptual models c...

We investigate the rupture process of the 25 April 2015 Gorkha earthquake (Mw=7.9) using a kinematic joint inversion of teleseismic waves, strong-motion data, high-rate GPS, static GPS and SAR data. The rupture is found to be simple in terms of coseismic slip and even more in terms of rupture velocity, as both inversion results and a complementing...

The Andes-Altiplano orogenic system, one of the most significant topographic feature on Earth, is the case example of subduction-type mountain belts. This latter conceptual model considers that the overall structure of the mountain belt forms antithetic to the subduction zone which marks the main plate interface, and as such poses several mechanica...

Assessing seismic hazards remains one of the most challenging scientific issues in Earth sciences. Deep tectonic processes are classically considered as the only persistent mechanism driving the stress loading of active faults over a seismic cycle. Here we show via a mechanical model that erosion also significantly influences the stress loading of...

The Chelungpu fault ruptured during the September 1999 Mw 7.6 Chi-Chi earthquake, in Central Taiwan. This event was characterized by coseismic displacements that increase along-strike and updip, from south to north. This variation in coseismic slip appears correlated to the geometry and segmentation of the thrust fault. Previous studies suggested t...

We propose to test if gravimetry can prove useful in discriminating different models of long-term deep crustal processes in the case of the Taiwan mountain belt. We discuss two existing tectonic models that differ in the deep processes proposed to sustain the long-term growth of the orogen. One model assumes underplating of the uppermost Eurasian c...

Ten years ago, Central Taiwan was struck by the Mw=7.6 ChiChi earthquake. A progressive northward increase in coseismic slip was observed and several explanations have been proposed in the literature to account for this. Recently, based on structural and morphotectonic analyses in the southern portion of the fault, we proposed that these lateral va...

The orogenic wedge of Taiwan results from the late Miocene collision of the Chinese passive margin and the Luzon volcanic arc. Because of the southward propagation of the collision over time, and because of its extreme rates of deformation and erosion, it has appeared as an ideal place to investigate mountain building processes. Here, we review exi...

Terra Nova, 23, 85–91, 2011 Vitrinite reflectance and Raman spectroscopy of carbonaceous material data are used to better resolve the thermal history of the Hsuehshan Range, which is accreted between the foreland fold–thrust belt and bulldozer hinterland units in the Taiwan mountain belt. The observed thermal data indicate that the strata in the no...

Although critical to a variety of issues in Earth Sciences, paleotopography remains poorly constrained over the geological past. Indeed, sediments preserve a record of the history of the Earth surface, but deconvolving these archives remains a challenge in the absence of a proper quantification of surface processes at the large spatial and temporal...

The central range (CR) of Taiwan is composed of a Cenozoic slate belt and the pre-Tertiary Tananao schists. Ongoing crustal shortening has resulted from the collision between the Chinese continental margin and the Luzon volcanic arc, which started ~6.5 Myr ago. Due to the obliquity of the subduction relative to the continental margin, the collision...

Abstract The Taiwan orogen has been the focus of a number of models of mountain building processes, but little attention has been paid to high-pressure (HP) metamorphic rocks that are found as exotic blocks intermingled within the deepest units of the mountain belt. In this study, we re-appraise from updated petrological and thermodynamic databases...

The advent of space geodesy has revolutionized our ability to measure surface displacements and crustal strain along plate boundaries or across deforming continental areas. Some examples from Taiwan, the Nepal Himalaya and Sumatra where geologic, geodetic and plate motion data can be compared will be reviewed in the presentation. It will be shown t...

The Taiwan mountain belt is composed of a Cenozoic slate belt (Hsuehshan Range units, HR, and Backbone Slates, BS) and of accreted polymetamorphic basement rocks (Tananao Complex, TC). Ongoing crustal shortening has resulted from the collision between the Chinese continental margin and the Luzon volcanic arc, which initiated ~6.5 Ma ago. The grade...

The Taiwan mountain belt is classically viewed as a case example of a critical wedge growing essentially by frontal accretion and therefore submitted to distributed shortening. However, a number of observations call for a significant contribution of underplating to the growth of the orogenic wedge. We propose here a new thermokinematic model of the...

We analyze the kinematics of fault tip folding at the front of a fold-and-thrust wedge using a sandbox experiment. The analog model consists of sand layers intercalated with low-friction glass bead layers, deposited in a glass-sided experimental device and with a total thickness h = 4.8 cm. A computerized mobile backstop induces progressive horizon...

The Pakuashan anticline is an active fault tip fold that constitutes the frontal most zone of deformation along the western piedmont of the Taiwan Range. Assessing seismic hazards associated with this fold and its contribution to crustal shortening across central Taiwan requires some understanding of the fold structure and growth rate. To address t...

The Chelungpu fault produced the September 1999 M_w = 7.6 Chi-Chi earthquake, central Taiwan. The shortening rate accommodated by this structure, integrated over several seismic cycles, and its contribution to crustal shortening across the Taiwanese range have remained unresolved. To address the issues, we focus our study on the Chelungpu and Chush...

The African topography is characterized by elevated regions (> 1000 m), such as over the South-African Plateau, and is quite intriguing because it does not relate to any orogenic and convergent setting. Several models have been proposed in the past to account for these topographic anomalies. However, clear geological constraints were lacking to dis...

The Taiwanese range has resulted from the collision between the Luzon volcanic arc and the Chinese continental margin, which started about 6.5 Myr ago in the north, and has since propagated southward. The building of the range has been recorded in the spatiotemporal evolution of the foreland basin. We analyze this sedimentary record to place some c...

Because of its high rates of convergence and erosion, the Taiwanese range is an ideal place to investigate the interactions between tectonics, erosion and climate. It has been viewed as a classical critical wedge essentially growing by frontal accretion of material. Such model of mountain-building is quite popular in numerical models that explore t...

The Taiwanese range has resulted from the oblique collision between the Luzon volcanic arc and the Chinese continental margin. Because of this obliquity, the collision started north of the island about 6.5 Myr ago, and has since propagated southward. The young and still ongoing Taiwan orogeny is an ideal place to investigate how the spatio-temporal...

The central range (CR) of Taiwan is composed of a Cenozoic slate belt and the pre-Tertiary Tananao schists (TS). Ongoing crustal shortening has resulted from the collision between the Chinese continental margin and the Luzon volcanic arc, which started ~6.5 Ma ago. Due to the obliquity of the Luzon arc relatively to the continental margin, the coll...

A current view is that the portion of the subduction interface that remains locked in the time interval between large interplate earthquakes, hereinafter referred to as the locked fault zone (LFZ), does not extend into the mantle because serpentinization of the mantle wedge would favor stable aseismic sliding. Here, we test this view in the case of...

The Pakuashan anticline is an active fault-propagation fold which constitutes the most frontal zone of deformation along the Western Foothills of central Taiwan. This blind fault is thought to be responsible for the 1848 Changhua earthquake, M~7.1, and to be currently locked. Previous studies mostly based on balanced cross-sections, have suggested...

A current and most accepted view about the seismogenic zone along subduction zones is that the downdip extent of the locked fault portion would correspond either to the 350° C isotherm if this temperature is reached above the Moho, or to the intersection with the forearc Moho for colder subduction zones [Oleskevich et al., 1999]. This limit would r...

The current view is that the downdip extent of the seismogenic zone along subduction zones would correspond to the 350°C isotherm when this temperature is reached above the Moho, or else at the Moho depth itself [e.g., Oleskevitch et al., 1999]. The explanation generally put forward is that this limit corresponds to the transition from slip-weakeni...