SIAME Louis Lionel

Associate Professor (Aix-Marseille University)         

Visiting Associate Research Fellow at Institute of Earth Sciences (Academia Sinica)

TEL: 02-2783-9910 ext 406 CELL: 09-1240-7013

E-mail: siame@cerege.fr

www.cosmoland.fr

Specialty: Active Fault and Active Tectonics, Structural Geomorphology,

In Situ-Produced Cosmogenic Nuclides

Education

·         2009, Accreditation to Supervise Research (Habilitation à Diriger des Recherches) in Geosciences (Morphogenesis and Cosmogenic Nuclides), Université Aix-Marseille.

·         1998, Ph.D. in Geosciences (active tectonics, in situ-produced cosmogenic nuclides), Université Paris XI.

·         1994, Magistère in Geosciences, Université Paris XI, Paris VI and Ecole Normale Supérieure de Paris.

·         1991, B.S. in Geosciences, Université Paris XI.

Career Path

·         2007 to present: Co-director for the French side of the French-Taiwan International Laboratory ADEPT (Active Deformation and Environment Programme for Taiwan) jointly supported by French CNRS and Taiwanese NSC.

·         2004 to Present: Associate Professor at Aix-Marseille University

·         1999-2004: Assistant Professor at ParisXI university

Scientific skills

·         Quantify geodynamic processes at convergent plate boundaries on several ranges of spatial (from several meters to several hundred kilometers) and temporal (from current up to several million years in the past) scales.

·         Identify and characterize the active faults to evaluate their seismogenic behavior.

·         Understand and quantify the tectonic and climatic factors involved in the evolution of the Earth's surface.

·         Methodological developments to implement in situ produced cosmogenic nuclides in a greater variety of climatic and anthropogenic environments.

Awards

·         2010-2014: Scientific Excellence Award.

·         2004-2008: Supervision Doctoral Research Award

·         2000: Ph.D. Prize of the French National Committee of Geology (Geology of the Inner Earth).

Recent and significant articles since 2007

Siame, L.L., Chen, R.-F., Derrieux, F., Lee, J.-C., Chang, K.-J., Bourlès, D.L., Braucher, R., Léanni, Laetitia, Kang, Chu-Chun, Chang, C.-P., Chu, H.-T., 2012. Pleistocene alluvial deposits dating along frontal thrust of Changhua Fault in western Taiwan: The cosmic ray exposure point of view. Journal of Asian Earth Sciences, in press (doi:10.1016/j.jseaes.2012.02.002).

Siame, L.L., Angelier, J., Chen, R.-F., Godard, V., Derrieux, F., Bourlès, D.L., Braucher, R., Chang, K.-J., Chu, H.-T., Lee, J.-C., 2011. Erosion rates in an active orogen (NE-Taiwan): Erosion rates in an active orogen (NE-Taiwan): A confrontation of cosmogenic measurements with river suspended loads. Quaternary Geochronology, 6(2), 246-260 (doi:10.1016/j.quageo.2010.11.003).

Rixhon, G., Braucher, R., Bourlès, D.L., Siame, L.L., Bovy, B., Demoulin, A., 2010. Quaternary river incision in NE Ardennes (Belgium) – Insights from 10Be/26Al dating of river terraces. Quaternary Geochronology, 6(2), 273-284 (doi:10.1016/j.quageo.2010.11.001).

Braucher, R., Del Castillo, P., Siame, L.L., Hidy, A.J., Bourlès, D.L., 2009. Determination of both exposure time and denudation rate from in situ-produced 10Be depth profiles: a mathematical proof of uniqueness. Quaternary Geochronology 4, 56-67 (doi: 10.1016/j.quageo.2008.06.001).

Shabanian, E., Siame, L.L., Bellier, O., Abbassi, M., Benedetti, L. 2009. Quaternary slip-rates along the north-eastern boundary of the Arabia-Eurasia collision zone (Kopeh Dagh Mountains, North-East Iran). Geophysical Journal International 178, 2, 1055-1077 (doi: 10.1111/j.1365-246X.2009.04183.x).

Siame, L.L., Chu, H.-T., Carcaillet, J., Lu, W.-C., Bourlès, D.L., Braucher, R., Angelier, J., Dussouillez, P, 2007. Glacial retreat history of Nanhuta Shan (North-east Taiwan) from preserved glacial features: the Cosmic ray exposure perspective. Quaternary Science Reviews 26, 2185-2200.

 

Research highlights

 

Interested in the study of active deformations of continental lithospheres and particularly those occurring at convergent plate boundaries, my research work is based on observations, analyses and measurements, and aims at identifying and quantifying the active deformations as well as tracing the evolution of tectonic regimes through a combination of complementary approaches (tectonic, structural geomorphology, in situ-produced cosmogenic nuclides). Combined with data from geodesy, remote sensing or seismology, this strategy allows apprehending the deformation of continental lithospheres over several ranges of spatial (from several meters to several hundred kilometers) and temporal (since the present up to several million years back in the past) scales. I have been working on areas located in South America (Argentine Precordillera and Peruvian Cordillera Blanca), France (Provence), Morocco (High-Atlas and Anti-Atlas), Iran (Kopet-Dagh) and today Taiwan.

In the mid-1990's, the application procedures for in situ-produced cosmogenic nuclides have been validated for relatively ideal geomorphic features for which the processes (erosion, burial…) acting on the surface after their abandonment are very limited. Such favorable circumstances being encountered in arid regions, this environmental characteristic has prompted the pioneer applications in active tectonics. In Argentina, we proposed a multidisciplinary approach (structural geomorphology, seismotectonic, in situ-produced cosmogenic nuclides), which allowed identifying and quantifying active deformations in the Andean foreland (Siame et al., 1997; Siame et al., 2002), thereby allowing integrating the fault slip rates determined thanks to in situ-produced cosmogenic 10Be into a consistent regional seismotectonic model (Siame et al., 2005; Siame et al., 2006).

The impact of post-depositional processes (erosion, burial…) can complicate the evolution of geomorphic surfaces, and exposure ages derived from in situ-produced cosmogenic nuclide concentrations may not be representative for the actual abandonment age of the studied objects. To apprehend deformations cumulated over long time spans, it is necessary to analyze old and therefore degraded morphological signatures. The necessity to account for surface processes is thus particularly critical in areas where levels of deformation are low compared to human activity and climate dynamics. During the European project "SAFE", we studied settings that are characterized by slow deformation in South-eastern France (the Middle Durance Fault; Siame et al., 2004) and along the southern front of the Moroccan Atlas Mountains (Sébrier et al., 2006). Within this framework, methodological concepts have been developed to implement the in situ-produced cosmogenic nuclides to morphological markers whose surfaces can be disturbed by human activity or surface processes subsequent to their abandonment (Siame et al., 2004). The approach using measurement and modeling of cosmogenic nuclide concentrations along depth profiles sampled below the surface is now permitting to determine the exposure scenario of landforms exposed to cosmic rays (Braucher et al., 2009; Rixhon et al., 2011; Siame et al., 2012).

In the recent years, we investigated the northeast limit of the collision zone between the Eurasian and Arabian plates (Shabanian et al., 2009a; Shabanian et al., 2009b; Siame et al., 2009; Shabanian et al., 2010; Shabanian et al., 2012). Based on the methodological approach evoked above, we studied of the distribution and quantified rates of active deformation in the Kopeh Dagh and Binalud mountains (Shabanian et al., 2009a; Shabanian et al., 2012). During this project, we also characterized a transfer zone of deformation from the Kopeh Dagh Mountains towards the south of the Binalud Mountains (Shabanian et al., 2009b). Finally, we also determined the Plio-Quaternary stress states at the regional level in the mountains of Kopeh Dagh, Allah Dagh and Binalud (Shabanian et al., 2010). All together, these investigations conducted us to write a comment about the kinematic models en vogue for the region (Siame et al., 2009). Our data and observations suggest a simple kinematic model in which Central Iran and the Western Kopeh Dagh are translated northward with respect to Eurasia by focalized intracontinental strike-slip faulting along the plate boundary between Iran and Eurasia.

In the meantime, I also develop a growing interest in understanding the coupling relationships between tectonics, climate and erosion for a better quantification and modeling of the exhumation of rocks, structural evolution and kinematics of the Taiwanese orogenic wedge. This interest for the processes that control the evolution of morphological surfaces also encompasses the study of the glacial morphologies, and particularly those that are preserved in the highest part of the mountain range (Carcaillet et al., 2007; Siame et al., 2007). Dated using in situ-produced cosmogenic nuclides, those glacial relicts offer the opportunity to evaluate (1) the impact of climate in the topographic evolution, and (2) the extension of the Last Glacial period in South-eastern Asia. The research I am now developing in Taiwan aims at providing meaningful data to study the relief response to internal and external forcing factors. Within this framework, I want to address two aspects of the Taiwanese orogenic wedge dynamic. The first one deals with the topographic evolution of the wedge and the relationship between the development of the relief by internal processes and the rates of surface lowering due to erosion. This part of my research involves the determination of denudation rates throughout the whole mountain range using in situ-produced cosmogenic 10Be concentrations measured in river-borne sediments and bedrock exposures compared with river suspended loads and thermo-chronological data. A first study has already been published for the Lanyang River watershed, in northeast Taiwan (Siame et al., 2011). The second aspect concerns the quantification of the deformation rates accommodated by the main active faults. This part of my research aims at deciphering how these deformation rates evolve on time scales spanning the last tens to hundreds of thousands of years and involves the dating of deformed alluvial landforms using in situ-produced cosmogenic 10Be concentrations measured along depth profiles. A first study has been published for the dating of Pleistocene alluvial deposits along the frontal thrust of Changhua Fault in western Taiwan. From the point of view of active tectonics, the comparison of the current geodetic-derived tectonic loading rates with the uplift/shortening rates derived from the cosmogenic chronological framework highlighted that the uplift/shortening rate absorbed by the Changhua Fault was not constant over the last 450 ka, with an acceleration starting roughly 200 ka ago to reach a significant proportion of the convergence rate circa 30 ka ago (Siame et al., 2012). This preliminary investigation has basically resolved a critical question: what is the timing for emplacement and abandonment of the alluvial terraces affected by the Changhua Fault? However, it raised another, deeper and perhaps more fundamental question about pulses in rates of deformation.

 


 

List of publications:

 

39 - Shabanian, E., O. Bellier, L. Siame, M. R. Abbassi, D. Bourlès, R. Braucher, and Y. Farbod, 2012. The Binalud Mountains: A key piece for the geodynamic puzzle of NE Iran. Tectonics 31, TC6003, (doi:10.1029/2012TC003183).

38 - Siame, L.L., Chang, C.-P., 2012. An Introduction to the Tectonophysics Special Issue "Geodynamics and Environment in East Asia" - Tribute to Jacques Angelier (1947-2010). Tectonophysics 578, 1-2 (doi: 10.1016/j.tecto.2012.06.025)

37 - Lee, B., Han, Y., Huh, Y., Lundstrom, C., Siame, L.L., Lee, J.I., Park, B.-K., ASTER Team, 2013. Chemical and physical weathering in south Patagonian rivers: A combined Sr–U–Be isotope approach. Geochimica et Cosmochimica Acta 101, 173-190 (doi: 10.1016/j.gca.2012.09.054).

36 - Demoulin, A., Beckers, A., Rixhon, G., Braucher, R., Bourles, D., Siame, L., 2012. Valley downcutting in the Ardennes (W Europe): Interplay between technically triggered regressive erosion and climatic cyclicity. Geologie en Mijnbouw/Netherlands Journal of Geosciences 91 (1-2), 79-90 (link to NJG).

35 - Siame, L.L., Chen, R.-F., Derrieux, F., Lee, J.-C., Chang, K.-J., Bourlès, D.L., Braucher, R., Léanni, Laetitia, Kang, Chu-Chun, Chang, C.-P., Chu, H.-T., 2012. Pleistocene alluvial deposits dating along frontal thrust of Changhua Fault in western Taiwan: The cosmic ray exposure point of view. Journal of Asian Earth Sciences 51, 1-20 (doi: 10.1016/j.jseaes.2012.02.002)

34 - Cossart, E., Fort, M., Bourlès, D.L., Braucher, R., Perrier, R., Siame, L., 2012. Deglaciation Pattern During the Lateglacial/Holocene Transition in the Southern French Alps. Chronological Data and Geographical Reconstruction from the Clarée Valley (Upper Durance Catchment, Southeastern France). Palaeogeography, Palaeoclimatology, Palaeoecology 315-316, 109-123 (doi: 10.1016/j.palaeo.2011.11.017).

33 - Cossart, E., Bourlès, D., Braucher, R., Carcaillet, J., Fort, M., Siame, L., 2011. L’englacement du haut bassin durancien (Alpes francaises du Sud) du Dernier Maximum Glaciaire à l’Holocène : Synthèse chronologique. Geomorphologie: Relief, Processus, Environnement 2, 123-142 (doi: 10.4000/geomorphologie.9336).

32 - Javidfakhr, B., Bellier, O., Shabanian, E., Siame, L., Léanni, L., Bourlès, D., Ahmadian, S., 2011. Fault kinematics and active tectonics at the southeastern boundary of the eastern Alborz (Abr and Khij fault zones): geodynamic implications for NNE Iran. Journal of Geodynamics 52 (3-4), 290-303 (doi: 10.1016/j.jog.2011.02.005).

31 - Le Dortz, K., Meyer, B., Sébrier, M., Braucher, R., Nazari, H., Benedetti, L., Fattahi, M., Bourlès, D., Foroutan, M., Siame, L., Rashidi, A., Bateman, M.D., 2011. Dating inset terraces and offset fans along the Dehshir fault combining cosmogenic and OSL methods. Geophysical Journal International 185 (3), 1147-1174 (doi: 10.1111/j.1365-246X.2011.05010.x).

30 - Rixhon, G., Braucher, R., Bourlès, D., Siame, L., Bovy, B., Demoulin, A., 2010. Quaternary river incision in NE Ardennes (Belgium) – Insights from 10Be/26Al dating of river terraces. Quaternary Geochronology, 6(2), 273-284 ( doi: 10.1016/j.quageo.2010.11.001).

29 - Siame, L.L., Angelier, J., Chen, R.-F., Godard, V., Derrieux, F., Bourlès, D.L., Braucher, R., Chang, K.-J., Chu, H.-T., Lee, J.-C., 2011. Erosion rates in an active orogen (NE-Taiwan): Erosion rates in an active orogen (NE-Taiwan): A confrontation of cosmogenic measurements with river suspended loads. Quaternary Geochronology, 6(2), 246-260 (doi: 10.1016/j.quageo.2010.11.003).

28 - Shabanian, E., Bellier, O., Abbassi, M.R., Siame, L., Farbod, Y., 2010. Plio-Quaternary stress states in NE Iran: Kopeh Dagh and Allah Dagh-Binalud mountain ranges. Tectonophysics 480, 1-4, 280-304 (doi : 10.1016/j.tecto.2009.10.022).

27 - Cossart, E., Fort, M., Bourlès, D.L., Carcaillet, J., Perrier, R., Siame, L., Braucher, R., 2010. Climatic Significance of Glacier Retreat and Rockglaciers Re-assessed in the Light of Cosmogenic Dating and Weathering Rind Thickness in Clarée Valley (Briançonnais, French Alps). Catena 80, 204-219 (doi : 10.1016/j.catena.2009.11.007).

26 - Le Dortz, K., Meyer, B., Sébrier, M., Nazari, H., Braucher, R., Fattahi, M., Benedetti L., Forouttan, M., Siame, L.L., Bourlès, D., Talebian, M., Ghoraishi, M., 2009. Holocene right-slip rate determined by cosmogenic and OSL dating on the Anar Fault, Central Iran. Geophysical Journal International 179, 2, 700-710 (doi: 10.1111/j.1365-246X.2009.04309.x).

25 - Siame, L.L., Shabanian, E., Bellier, O., 2009. Comment to “Extrusion tectonics and subduction in the eastern South Caspian region since 10 Ma” by Hollingsworth et al. (2008). Geology 37 (12), E197-E198 (doi : 10.1130/G25701C.1).

24 -  Shabanian, E., Bellier, O., Siame, L.L., Abbassi, M., Ghassemi, H., Arnaud, N., Cochemé, J.J., 2009. New tectonic configuration in NE Iran: active strike-slip faulting between the Kopeh Dagh and Binalud mountains. Tectonics 28, TC5002 (doi: 10.1029/2008TC002444).

23 - Shabanian, E., Siame, L.L., Bellier, O., Abbassi, M., Benedetti, L. 2009. Quaternary slip-rates along the north-eastern boundary of the Arabia-Eurasia collision zone (Kopeh Dagh Mountains, North-East Iran). Geophysical Journal International 178, 2, 1055-1077 (doi: 10.1111/j.1365-246X.2009.04183.x).

22 - Braucher, R., Del Castillo, P., Siame, L.L., Hidy, A.J., Bourlès, D.L., 2009. Determination of both exposure time and denudation rate from in situ-produced 10Be depth profiles: a mathematical proof of uniqueness. Quaternary Geochronology 4, 56-67 (doi: 10.1016/j.quageo.2008.06.001).

21 - Angelier, J., Chang, T.-Y., Hu, J.-C., Chang, C.-P., Siame, L.L., Lee, J.-C., Deffontaines, B., Chu, H.-T., Lu, C.-Y., 2009. Does extrusion occurs at both tips of the Taiwan collision belt? Insights from active deformation studies in the Ilan Plain and Pingtung Plain regions. Tectonophysics 466, 356-376 (doi: 10.1016/j.tecto.2007.11.015).

20 - Siame, L.L., Chu, H.-T., Carcaillet, J., Lu, W.-C., Bourlès, D.L., Braucher, R., Angelier, J., Dussouillez, P, 2007. Glacial retreat history of Nanhuta Shan (North-east Taiwan) from preserved glacial features: the Cosmic ray exposure perspective. Quaternary Science Reviews 26, 2185-2200 (doi: 10.1016/j.quascirev.2007.04.016).

19 - Carcaillet, J. , Siame, L.L., Chu, H.-T., Bourlès, D.L., Lu, W., Angelier, J., Dussouliez, P., 2007. First cosmogenic exposure dating (in situ produced 10Be) of the late Pleistocene and Holocene glaciation in Nanhutashan Mountains (Taiwan). Terra Nova 19, 331-336 (doi : 10.1111/j.1365-3121.2007.00756.x).

18 - Siame, L.L., Bourlés, D.L., and Brown, E.T., 2006. In Situ–Produced Cosmogenic Nuclides and Quantification of Geological Processes: Preface, v-vi (doi: 10.1130/0-8137-2415-5.v). Special Paper of the Geological Society of America 415, Boulder, USA, 158 p.

17 - Siame, L.L., Bellier, O., Sébrier, M., 2006. A seismotectonic model for the Argentine Precordillera and the western Sierras Pampeanas. Revista de la Asociación Geológica Argentina 61 (4), 604-619 (ISSN: 1851-8249).

16 - Siame, L.L., Sébrier, M., Bellier, O., Bourlès, D., 2006. Can cosmic ray exposure ages on the Cordillera Blanca escarpment reveal normal faulting activity? Revista de la Asociación Geológica Argentina 61 (4), 536-544 (ISSN: 1851-8249).

15 - Sébrier, M., Siame, L.L., Zouine, E., Winter, T., Missenard, Y., Leturmy, P., 2006. Active tectonics in the Moroccan High Atlas, Comptes Rendus Geosciences 338, 1-2, 65-79 (doi : 10.1016/j.crte.2005.12.001).

14 - Siame, L.L., Bellier, O., Sébrier, M., Araujo, M., 2005. Deformation partitioning in flat subduction setting: the case of the Andean foreland of Western Argentina (28°S-33°S): Tectonics 24, 1-24 (doi : 10.1029/2005TC001787).

13 - Siame, L.L., Bellier, O., Sébrier, M., Bourlès, D.L., Leturmy P., Perez, M., Araujo, M., 2005. Seismic hazard reappraisal from combined structural geology, geomorphology and cosmic ray exposure dating analyses: the Eastern Precordillera thrust system (NW-Argentina). Corrigendum Geophysical Journal International Vol. 161 Issue 2 Page 416 May 2005 (doi: 10.1111/j.1365-246X.2005.02542.x).

12 - Lacombe, O., Angelier, J., Mouthereau, F., Chu, H.-T., Deffontaines, B., Lee, J.-C., Rocher, M., Chen, R.-F., Siame, L., 2004. The Liuchiu Hsu island offshore SW Taiwan: tectonic versus diapiric anticline development and comparisons with onshore structures. Comptes Rendus Geosciences 336, 9, 815-825 (doi : 10.1016/j.crte.2004.02.007).

11 - Siame, L.L., Bellier, O., Braucher, R., Sébrier, M., Cushing, M., Bourlès, D., Hamelin, B., Baroux, E., de Voogd, B., Raisbeck, G., Yiou, F., 2004. Local erosion rates versus active tectonics: cosmic ray exposure modelling in Provence (south-east France). Earth and Planetary Science Letters 7010, 1-20 (doi : 10.1016/S0012-821X(04)00061-5).

10 - Brocard, G.Y., Van der Beek, P.A., Bourlès, D.L., Siame, L.L., Mugnier, J.L., 2003. Long term fluvial incision rates and post glacial river relaxation time in the French Western Alps from 10Be dating of alluvial terraces with assessment of inheritance, soil development, and wind ablation effects. Earth and Planetary Science Letters 197, 197-214 (doi : 10.1016/S0012-821X(03)00031-1).

9 - Siame, L.L., Bellier, O., Sébrier, M., Bourlès, D.L., Leturmy, P., Perez, M., Araujo, M., 2002. Seismic hazard reappraisal from combined structural geology, geomorphology and cosmic ray exposure dating analyses: the Eastern Precordillera thrust system (NW-Argentina). Geophysical Journal International 149, 1-20 (doi : 10.1046/j.1365-246X.2002.01701.x).

8 - Jackson, J., Ritz, J.-F., Siame, L.L., Raisbeck, G.M., Yiou, F., Norris, R., Youngson, J., 2002. Fault growth and landscape development rates in Otago, New Zealand, using in situ cosmogenic 10Be. Earth and Planetary Science Letters 195, 185-193 (doi : 10.1016/S0012-821X(01)00583-0).

7 - Bellier, O., Sébrier, M., Beaudouin, T., Villeneuve, M., Braucher, R., Bourlès, D., Siame, L.L., Putranto, E., Pratomo, I., 2001. High slip rate for a low seismicity along the Palu-Koro active fault in Central Sulawesi (Indonesia). Terra Nova 13, 463-470 (doi : 10.1046/j.1365-3121.2001.00382.x)

6 - Siame, L.L., Braucher, R., Bourlès, D.L., Bellier, O., Sébrier, M., 2001. Datation de surfaces géomorphologiques repères par le 10Be produit in-situ : implications tectoniques et climatiques. Bulletin de la Société Géologique de France 172, 2, 223-236 (doi : 102113/172.2.223).

5 - Braucher, R., Siame, L.L., Bourlès, D.L., Colin, F., 2000. Le 10Be produit in-situ : dynamique des sols et évolution des paysages. Bulletin de la Société Géologique de France, 171, n°5, 511-520 (doi : 102113/171.5.511).

4 - Siame, L.L., Braucher, R., Bourlès, D.L., 2000. Les nucléides cosmogéniques produits in-situ : de nouveaux outils en géomorphologie quantitative. Bulletin de la Société Géologique de France 171, 4, 383-396 (doi : 10.2113/ 171.4.383).

3 - Giuliani, G., Bourlès, D.L., Massot, J., Cheilletz, A., Siame, L.L., 1999. Colombian emerald reserves inferred from leached beryllium of their hosting black shale. Exploration and Mining Geology, Special Issue on Mineral deposits in Latin America, 8, 1-2, 109-116.

2 - Siame, L.L., Bourlès, D.L., Sébrier, M., Bellier, B., Castano, J.C., Araujo, M., Perez, M., Raisbeck, G.M., Yiou, F., 1997. Cosmogenic dating ranging from 20 to 700 ka of a series of alluvial fan surfaces affected by the El Tigre fault, Argentina. Geology 25 (11), 975-978 (doi : 10.1130/0091-7613).

1 - Siame, L.L., Sébrier, M., Bellier, O., Bourlès, D., Castano, J.C., Araujo, M., 1997. Geometry, segmentation and displacement rates of the El Tigre fault, San Juan Province (Argentina) from SPOT image analysis and 10Be datings, Annales Tectonicae, Vol. XI – N. 1-2, 3-26.