Directeur de Recherche
Transcription
Directeur de Recherche
Present position • Senior researcher (Directeur de Recherche) for CNRS since 2006, working for CNRS since 1993 • Head of the Departement of Eart, Water and Environmental Sciences Université of Montpellier 2 Academic Positions • 2002- 2005 o Junior researcher in CNRS-unit “Dynamique de la Lithosphere” of CNRS, Montpellier o Head of the rare gaz thermochronology laboratory • 1993-2002 o Junior researcher in CNRS-unit “Magmas et Volcans”, Clermont Ferrand • 1992-1993 o Post doc in Dept of Earth Sciences, Open University, Milton Keynes UK Visiting positions • Earth and Space Sciences Department, at UCLA, California, 1990-1991 • Training in Professeur T.M HARRISON's laboratory • Weak Radioactive Sources Centre, laboratory CNRS/CEA, Gif sur Yvette, Fission Tracks method and its contributions, with J. CARPENA. • 3 weeks visit in Sakurajima Volcanological Observatory during 1987 and 1988. University studies: • PhD at Clermont-Ferrand 2 University and Research Department N°10 of CNRS. Subject: Apports de la thermochronologie 40Ar/39Ar à la connaissance de la tectonique cénozoïque d'Asie. Defended April 10th 1992, with "Mention Très Honorable et les Félicitations du Jury". • Advisor: Prof Ph. VIDAL • Advanced level studies of Petrology, Geochemistry and Volcanology passed at ClermontFerrand 2 University, in June 1989, "Mention Très Bien", Head of the list. Research subject: The trachytic eruptions of the Chaîne des Puys (French Massif Central) Contribution of the study of cogenetic enclaves. • Master of Earth Sciences, Petrology-Geochemistry speciality passed at Aix-Marseille 3 University, in June 1988, "Mention Bien", Head of the list. • Licence of Earth Sciences, passed at Aix-Marseille 2 University, in June 1987, "Mention Bien", Head of the list. • DEUG A, Mathematic and Physic Sciences, passed at Aix-Marseille 3 University, in June 1986, "Mention Bien" • Baccalaureat, Maths and Physics speciality, passed in June 1984, "Mention Bien" Professional Experience. • Mastering of the conception building and operation of a rare gaz laboratory • Mastering of complex thermochronological systems, diffusion dynamics and applications to geosciences • Use of most geochronological systems and knowledge of solid isotope geochemistry techniques. • Use of complexe geochemical and especially isotopical modeling in igneous processes • • Mastering of object oriented programming, notably those used to control electronic systems. Mastering of calculation oriented programming • Official training and agreement to work in radioactive environements. • • Preparation and animation of complex field studies in China (12 missions) Frequent field trips • • • English fluently spoken and written (some professional translations made in several scientific fields). Spanish fluently spoken and written. Italien: spoken. Societies membership • Member of the Société Géologique de France, the European Union of Geosciences and the American Union of Geophysics. • Member of the Section de Volcanologie de la S.G.F. • Member of the French Society for Geodesy and Geophysics Teaching and advisory duties From 1996 to 2004 • • • 40 to 50 hours annual in general geology petrology and physics from undergraduate to graduate levels 15 to 20 h annual in geochronology/thermochonology and physics at the Master level Teaching field trips Advisoring since 1996 • • • • • Co-supervising of F. Valli PhD on “Tectonics and geochronology of the Karakorm lithospheric strile slip fault”, to be defended at the end of 2005 Co-supervising of S. Garcia PhD defended in 2003 on “Timing of rfit jumps in iceland and constraints on geodynamicl rift models” PhD supervising of C. Mock defended in 1999 on « Cooling histories as revealed through thermochronology in contrasted geodynalical settings : tibet abnd the Red Sea rift » 8 Master levels training memoirs (one year each) Regular undergraduate trainings Scientific information and popular science • • • • • Paper on « The age of mountain ranges » in popular science journal « La Recherche » (November 1998) Editore of a booklet on « Radioactivity in the Environement and Sciences » in 1999 Otganizing of city pannel around the Challenge of Enery supplies at the local scale in 1999 Co-creator and animator of a « Science Bar » which gathers more than 100 people every months around a debated scientific theme. Regular conferences to schools and public audiences and animations around science. Review pannels, science administration and animation. National pannels and science administration • Head of Universe Science Departement at the University of Montpellier, and Director of the CNRS research federation 2035 « ISTEEM » (Institute for Earth, Environnement and Spaces sciences of Montpellier). • • • • • • • • Principal Investigator of research program "Age and propagation of the North Anatolian Fault" of National CNRS program “Structure of Deep Earth”, 2004-2007. Member of the national commission for junior reserachers appointment of CNRS 2000-2004 Animation of research theme "vertical movements in the continental lithosphere" of National CNRS program “Structure of Deep Earth”, 2000-2002 Co Animation of research theme “Ultra High pressures” of National CNRS program “Structure of Deep Earth”, 1998-2000. Member of the scientific commitee of the National Institute for Universe Sciences (INSU) since 2000 Member of the scientific commitee of the Department of Universe Sciences of CNRS since 2000 Member of the commission for geochemical equipment of the National Institute for Universe Sciences (INSU) 1996-2000 Regular PhD and laboratories evaluation pannels for CNRS and Universities Local responsabilities • In charge of the geochronology laboratory in Clermont-Ferrand 1992-2002, then in Montpellier since 2002 • In charge of Departement logistics in clermont-Ferrand 1998-2001 • In charge of seminars in Clermont-Fd, 1996-1999. • Member of local university commissions for associate professors appointements in Clermont Ferrand then Montpellier since 1996 Animation of science • Organizer of session “Geochronology” Goldschmidt conference in Toulouse in1998 • General Secretary of t French Physical Society meeting inClermont-Fd, in 1999 and animation of session “Environnemental Physics” • Organizer of session “Precise isotope dating of key geological events: techniques and methodologies leading to the goal of true ages” EGS-EUG-AGU meeting in 2003 • Member of the scientific commitee of the Himalayan Karakorum Tibet workshop organized in France in april 2005 Synthesis of research works. The 40Ar/39Ar methode has grown a rapidly growing interest at the end of the 60’ associated with the developement of a new generation of mass spectrometers and gaz extration techniques. With the application of the technique to a wide variety of geodynamical problems, several potnetial flaws also appeared more clearly, especially when 40Ar/39Ar ages were progressively compared to other independent information or other geochronological data. It needed more than 20 years before the comprehension of loss and inheritage in isotopic systems was sufficiebnt the physically rationalize the physical behavior of the K/Ar system, opening the field of thermochronology with a variety of unique and exciting applications. Since then thermochronology has become and an unescapable tool in a variety of geosciences fields and especially tectonics and geodynamics. My own scientific path has been focussed on the physical rationalization of argon loss and inheritage in complex mineralogical systems, and its application to continental tectonics and plate tectonics through the evaluation of the pertinence of resulting cooling histories. Open isotopic systems: experimental calibration. Among the various causes that may cause opening of the isotopic systems, temperature is probably the most efficient. It is especially with argon, which isotope of mass 40 is the natural daughter of 40K which easily diffuses in mineral lattices. If one can determine the physical laws dringin argon diffusion and extrapolate those to natural conditions then it is possible to derive a closing temperature, or a range of closure temperatures, which lead to a continuous Temperature/time curve, which may prove diagostic of a specific tectonic process or succession of tectonic processes. Among the mineralogic phases suitable to such and apporach K-feldspars are king : ubiquist, exceptionnaly rich in K, and wtaer free thus more resistant to argon extraction during laboratory experiements than most other K-bearing phases. Following pionneer works made in the the US, I have myself calibrated loss processes through experimental and applied approaches (Arnaud and Kelley, 1997; Arnaud and Eide, 2000…) with or without deformation in K-Feldspars allowing for the credibility of the methods to be demonstrated in many environnements and situations if one is carefull with the experimental and modelling protocols. It is clear that diffusive loss in natural geologicl systems is probably very complex, but it appears that a simple model does satisfactorely explains and predicts bahaviors which can be replicated in laboratory of extracted from natural samples, a situation which may be compared to the duality of macroscopic thermodynamic versus precise atomic physics, or the application of experimental petrology works in the extraction of natural (P,T) paths. I have since then applied this technique with success in various collaborative studies. The experimental protocols developped in the course of those studies have often accompanied breakthough technological advances, like the first use of UV laser in argon geochronology for example (Kelley at al., 1994; Arnaud and Kelley, 1995 for example). Inheritage in isotopic systems. Although argon solubility in minerals is usually low, it happens that some argon is inheritaed in geological systems from previous geological history. This is especially the case of ultra high pressure rocks especially when dry continental rocks are burried at 3-5 GPa. In those rocks, and until recent progresses in Lu/Hf and Sm/Nd, the 40Ar/39Ar technique was, and often still is, the only geochronolical tool. The wide variety of 40 Ar/39Ar ages on such rocks, especially in the Alps, had led in the late 80’ to very complex scenarios. Using the UV laser technique I could demonstrate for the first time and explain the wide occurrence of excess argon in high pressure rocks, a phenomenon which has since been largely confirmed and unfortunately seems almost geneticallya ssocited to the mode of metamorphism of these rocks hich prohibits fluid exchange and argon loss, leading to a strong solubility of inherited argon in neoformed minerals. I have led several programs in France on the study of isotopic equilibrium during HP metamorhism and I continue to ork on diagnostic tools which would allow for the identification and maybe some correction for excess argon in HP/UHP rocks. Methodology and geodynamical applications : Plate Tectonics « on shore » Geochronology is not a goal on its own, and must be developped to answer major geological questions. With that certitude in mind I have always led my experimental work on geological objecst which dragged important geodynamical problems, escpecially the large translithopsheric strike slip faults. Those faults are probably major discriminants in assessing whether or not Plate Tectonics doe apply “on shore”. Unfortunatly those major faults are often a nightmare for geochronologist since their limited exhumation offers only brittle of even colder deformation. Rarely do hey allow direct dating of well developped ductile fabrics. However a long and detailed work from direct dating of these faults wherever possible and the cooling histories of sirrounded ranges show that often ages are inheritaed from a long history. This is especially true for North Tibet strike slip faults which essentielly show Paleozoic and Mesozoic ages in deformation corridor which at first glance share all kinematic indicatprs compatabile with recent or present day deformation. This is the undisputable prrof that the Cenozoic strike slip fault have followed, wherever possible, inheritated lithopsheric heteorgeneites (Arnaud et al., 2003, Delville, Arnaud et al., 2001). Very practically this implies that estimation of Cenzoic offsets using pre-Tertiary piercing points will lead to spurrious estimations. This shows also how the study of pre-Cenozoic gelogical history is a key element in analysing the effects of the last collision in Asia, and this is also a significant part of my activity (Roger, Arnaud et al., 2003 for example). Hopefuly, there exist cases in which the inheritage is less important, essentielly when Cenozoic faults ahev developped oblique to preexisting structures. This is the case of the Karakorum fault. Detailed geochronological and thermochronological work show that the fault has been active since 22-25 Ma with a probable offset of at elast 300 Km, and a significat change in its partitionaing of deformation with a major normal throw component in the last 10 Ma (Valli, Arnaud et al., in press for Tectonics ; Lacassin Valli, Arnaud et al., 2004). I have led several programs on various geodybamical targets, all centered around continental tectonics which have led to several publications (Leloup, Arnaud et al., 2001; Mock, Arnaud et al., 1999; Sobel et Arnaud 1999b; Faure et al., 2003 for example). A window on the mantle : collision zones volcanism While studying collision zones, one often wished he could get informations on the eveolution of the mlantle at depth during collision. This is sometimes possible with “polaroid” snapshots of the rpesent day state of the mantle though geophysical imaging. However the study of collision magmatism and especially volcanism is also a way to “peep” on the mantle at various times during collision. I have studied volcanism in Tibet and Turkey spatially associated with collision and strike slip faults (Sobel et Arnaud, 1999a; Adyaman, Chorowitcz, Arnaud et al, 2001). An important conclusion is that the chemical signature of the magmatism is not, in itself, discriminant on the processes at depths. Always the subcontinental mantle is the source of the magmas and the principal genitor of their chemical signature, more an effect of the extreme ease of that mantle to melt after millions of years of enrichement through successive subduction than a proof of an obnormal thermal state at various times. However and intresteing paradigm is the very little contamination effect that the overthickened crust has on thos mantellic magmas, probably both because of their exceptionnaly and unusual enrichement in trace elements and also their close mechanical association with trifts or srtike slip faults. Dating of volcanoes : geodynamics, structural evolution of volcanoes and associated hazards. The 40Ar/39Ar methodo is well suited for the dating of volcanic rocks with a variety of geodynamical applciations. Rift jump in iceland Due to the westward American-Eurasian plate boundary migration, the rift zone location in Northern Iceland imposed by the stable Icelandic hotspot has jumped eastward. The present-day North Volcanic Zone of Iceland is thus shifted about 100 km to the east with respect to the Kolbeinsey Ridge. A Miocene paleo-rift location was proposed along the Húnaflói-Skagi axis. Unconformities inside the lava pile on both sides of the present-day rift as a result of the new rift formation have been used to date the rift jump, but timing is still controversial. Whether extinction of the paleo-rift was synchronous with initiation of the new rift or the two rifts were active during some time period is unknown. Using the 40Ar/39Ar radiochronology method, 100 dykes were dated along a 350 km profile parallel to the divergent plate motion direction (i.e., ESE-WNW) crossing the present rift, the unconformities, and the inferred paleo-rift. Our results reveal that the paleo-rift axis was not located along the Húnaflói-Skagi axis, but 60 km to the east. It remained active until approximately 3 Ma. The activity of the present North Volcanic Zone started about 8-8.5 Ma, intruding 9-9.5 My rocks located 10 km east of the Skagafjördur paleo-rift axis, this 10 km dimension of the rift jump being a lower bound. Consequently, the two rifts were simultaneously active for 5-5.5 My. During this time period, their accretion rates were nearly equal but with asymmetrical opening, the largest rates occurring on external flanks. These results are coherent in the Icelandic context and permit a first reconstruction of the evolution of Northern Iceland since 10 Ma. toute l’Islande. This work was published in EPSL (Garcia, Arnaud et al., 2003). Large ignimbritic eruptions on canaries Islands (Spain) In Tenerife (« Decade volcano » in EEC programs) several ignimbritic phases have existed prior to the present day cycle. Their dating is of course important for the assessemnt of hazard on tenerife, but proves decisive in reconstructing the erutpion phases and the cntinuity of producst which facies vary strongly from near crater to distal positions. This work has proved that flank failure and related avalanches and debris flows are at least as important as classical caldera forming events associated with important ignimbritic eruptions (Huertas ,Arnaud et al., 2002), which have existed on Tenerife repeteadly during the last 3 Ma. A hint on future works Very rapidly stated, my research path will certainly follow two complementary directions: • the combination of low and very low temperature thermochronology to address the timing of relief forming processings where external forcing (climate, hydrology etc…) and tectonics interact. I am leading the development of a U-Th/He facility in Montpellier which will allow, starting at the end of 2005, to engage new programs in the Chinese Tien Shan, Tibet, Anatolia and the Andes. Strong collaborations, already in place, with cosmogenic dating facilites will allow to address the ultimate point of the (T,t) paths… the surface. The ambitious goal is to be able, in the future, to extract from low temperature thermochronologcal tendancies the tectonic and external participations. • The dating of isotopically desequilibrated rocks because of especially low temperature and/or exceptionnaly fast conditions of forming. This is the case of gouges, fault breccias and pseudotachylites. Although numerous attemps at dating those rocks have been carried out it remains difficult to assess whether or not an age is significant because the conditions of inheritance or conservation of isotopic ages remains ubadly understood. However those rocks are more and more key elements in the reconsruction of large scale geodynamical models, especially when one is interested in recent or present day geodynamics. Through a combined expeimental and applied apporached of pseudotachylites from various “simples” cases we hope to offer such a rationalisation of the geochronology of those rocks. • Of course I want to apply those tools to continetal geodynamics, and especially to the estimation of velocities on the geological scale, to be compared to the ongroing database of geodesic velocity and strain fields. It becomes clear that in many occasions long term veolocites and presentd ay measures diverge strongly and it remains to assess for example whether this is the expression of a transcient state of the lithosphere on small time scales, or a problem in the extrapolation of geological salce velocities. Behind thos question one will easily recognize the fundamental question of the rheology of the continental lithosphere on various time scales and the remaining open question of whether or not Platea tectonics is aplicable on shore. Research production International papers with peer review. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. Arnaud, N.O., R. Xu, and Y. Zhang, Nouvelles donnees thermochronologiques sur le batholite du Kunlun et l'histoire thermique du Nord du Plateau Tibetain. Comptes Rendus de l'Academie des Sciences, Serie 2, Mecanique, Physique, Chimie, Sciences de l'Univers, Sciences de la Terre, 1991. 312(8): p. 905-911. Arnaud, N.O., A. Gourgaud, and G. Camus, Sur la signification des enclaves des trachytes de la Chaine des Puys (Massif Central francais). The significance of enclaves in trachytes from the Chaine des Puys, French Massif Central. Comptes Rendus de l'Academie des Sciences, 1992. Serie 2(Mecanique): p. Physique. Arnaud, N.O., P. Vidal, P. Tapponnier, P. Matte, and W.M. Deng, The high K2O volcanism of northwestern Tibet; geochemistry and tectonic implications. Earth and Planetary Science Letters, 1992. 111(no.2-4): p. pp.351-367. Arnaud, N.O., M. Brunel, J.M. Cantagrel, and P. Tapponnier, High cooling and denudation rates at Kongur Shan, eastern Pamir (Xinjiang, China) revealed by (super 40) Ar/ (super 39) Ar alkali feldspar thermochronology. Tectonics, 1993. 12(no.6): p. pp.1335-1346. Brunel, M., N. Arnaud, P. Tapponnier, Y. Pan, and Y. Wang, Kongur Shan normal fault; type example of mountain building assisted by extension (Karakoram Fault, eastern Pamir). Geology (Boulder), 1994. 22(no.8): p. pp.707-710. Kelley, S.P., N.O. Arnaud, and A.I. Okay, Anomalously old Ar-Ar ages in high pressure metamorphic terrains. Mineralogical Magazine, 1994. v.58A: p. 468-469. Kelley, S.P., N.O. Arnaud, and S.P. Turner, High spatial resolution (super 40) Ar/ (super 39) Ar investigations using an ultra-violet laser probe extraction technique. Geochimica et Cosmochimica Acta, 1994. 58(no.16): p. pp.3519-3525. Arnaud, N.O. and S.P. Kelley, Evidence for excess argon during high pressure metamorphism in the Dora Maira Massif (Western Alps, Italy), using an ultra-violet laser ablation microprobe (super 40) Ar- (super 39) Ar technique. Contributions to Mineralogy and Petrology, 1995. 121(no.1): p. pp.249-264. Lacassin, R., U. Schaerer, P.H. Leloup, N. Arnaud, P. Tapponnier, X. Li, and L. Zhang, Tertiary deformation and metamorphism SE of Tibet; the folded Tiger-leap Decollement of NW Yunnan, China. Tectonics, 1996. 15(3): p. 605-622. Matte, P., P. Tapponnier, N. Arnaud, L. Bourjot, J.P. Avouac, P. Vidal, L. Qing, Y. Pan, and Y. Wang, Tectonics of western Tibet, between the Tarim and the Indus. Earth and Planetary Science Letters, 1996. 142(3-4): p. 311-330. Turner, S., N. Arnaud, J. Liu, N. Rogers, C. Hawkesworth, N. Harris, S. Kelley, C.P. van, and W. Deng, Post-collision, shoshonitic volcanism on the Tibetan Plateau; implications for convective thinning of the lithosphere and the source of ocean island basalts. Journal of Petrology, 1996. 37(1): p. 45-71. Xu, R., Z. Yuquan, X. Yingwen, P. Vidal, N. Arnaud, Z. Qiaoda, and Z. Dunmin, Isotopic geochemistry of plutonic roks, in Geological evolution of the Karakoram and Kunlun mountains, P. Yusheng, Editor. 1996, Seismologic Press: Beijing. p. 137-186. Arnaud, N.O. and S.P. Kelley, Argon behaviour in gem-quality orthoclase from Madagascar; experiments and some consequences for (super 40) Ar/ (super 39) Ar geochronology. Geochimica et Cosmochimica Acta, 1997. 61(no.15): p. pp.3227-3255. Ancochea, E., J.M. Cantagrel, J.M. Fuster, M.J. Huertas, N.O. Arnaud, J. Marti, M. Huerlimann, G. Ablay, and A. Gudmundsson, Vertical and lateral collapses on Tenerife (Canary Islands) and 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. other volcanic ocean islands; discussion and reply. Geology (Boulder), 1998. 26(no.9): p. pp.861-863. Chataigner, C., J.L. Poidevin, and N.O. Arnaud, Turkish occurrences of obsidian and use by prehistoric peoples in the Near East from 14,000 to 6000 BP. Journal of Volcanology and Geothermal Research, 1998. 85(1-4): p. 517-537. Honthaas, C., J.P. Rehault, R.C. Maury, H. Bellon, C. Hemond, J.A. Malod, J.J. Cornee, M. Villeneuve, J. Cotten, S. Burhanuddin, H. Guillou, and N. Arnaud, A Neogene back-arc origin for the Banda Sea basins; geochemical and geochronological constraints from the Banda ridges (East Indonesia). Tectonophysics, 1998. 298(4): p. 297-317. Rossi, P., P. Guennoc, J.P. Rehault, N.O. Arnaud, B. Jakni, G. Poupeau, M. Tegyey, J. Ferrandini, M. Sosson, M.O. Beslier, N. Rollet, and R. Gloaguen, Importance du volcanisme calco-alcalin miocene sur la marge sud-ouest de la Corse (campagne MARCO). Importance of Miocene calc-alkalic volcanism along the southwestern Corsican margin; MARCO cruise. Comptes Rendus de l'Academie des Sciences, 1998. Serie II. Sciences de la Terre et des Planetes(vol.327): p. no.6. Ancochea, E., M.J. Huertas, J.M. Cantagrel, J. Coello, J.M. Fuster, N. Arnaud, and E. Ibarrola, Evolution of the Canadas edifice and its implications for the origin of the Canadas Caldera (Tenerife, Canary Islands). Journal of Volcanology and Geothermal Research, 1999. 88(no.3): p. pp.177-199. Cantagrel, J.M., N.O. Arnaud, E. Ancochea, J.M. Fuster, and M.J. Huertas, Repeated debris avalanches on Tenerife and genesis of Las Canadas caldera wall (Canary Islands). Geology (Boulder), 1999. 27(no.8): p. pp.739-742. Eide, E.A., T.H. Torsvik, T.B. Andersen, and N.O. Arnaud, Early Carboniferous unroofing in western Norway; a tale of alkali feldspar thermochronology. Journal of Geology, 1999. 107(no.3): p. pp.353-374. Guivel, C., Y. Lagabrielle, J. Bourgois, R.C. Maury, S. Fourcade, H. Martin, and N. Arnaud, New geochemical constraints for the origin of ridge-subduction-related plutonic and volcanic suites from the Chile Triple Junction (Taitao Peninsula and Site 862, LEG ODP141 on the Taitao Ridge). Tectonophysics, 1999. 311(no.1-4): p. pp.83-111. Jolivet, M., F. Roger, N. Arnaud, M. Brunel, P. Tapponnier, and D. Seward, Histoire de l'exhumation de l'Altun Shan : indications sur l'âge de la subduction du bloc du Tarim sous le système de l'Altyn Tagh : Nord Tibet. C. R. Acad. Sc., Paris, 1999. t.. 329, série IIa: p. 749-755. Mock, C., N. Arnaud, and J.M. Cantagrel, 40Ar/39Ar Thermochronology of the Ethiopian and Yemenite basements : post orogenic slow cooling or reheating related to the Afar plume?,. Tectonophysics., 1999. 314: p. 351-372. Mock, C., N.O. Arnaud, and J. Cantagrel, Marie, An early unroofing in northeastern Tibet? Constraints from (super 40) Ar/ (super 39) Ar thermochronology on granitoids from the eastern Kunlun Range (Qianghai, NW China). Earth and Planetary Science Letters, 1999. 171(no.1): p. pp.107-122. Monzier, M., C. Robin, P. Samaniego, M.L. Hall, J. Cotten, P. Mothes, and N. Arnaud, Sangay Volcano, Ecuador; structural development, present activity and petrology. Journal of Volcanology and Geothermal Research, 1999. 90(no.1-2): p. pp.49-79. Reddy, S.M., G.J. Potts, S.P. Kelley, and N.O. Arnaud, The effects of deformation-induced microstructures on intragrain (super 40) Ar/ (super 39) Ar ages in potassium feldspar. Geology (Boulder), 1999. 27(no.4): p. pp.363-366. Sherlock, S.C. and N.O. Arnaud, Flat plateau and impossible isochrons; apparent (super 40) Ar(super 39) Ar geochronology in a high-pressure terrain. Geochimica et Cosmochimica Acta, 1999. 63(no.18): p. pp.2835-2838. Sobel, E. and N. Arnaud, Cretaceous - Paleogene basaltic rocks of the Tuyon basin, NW China and the Kyrgyz Tian Shan: the trace of limited plume event? Lithos, 1999. 50: p. 191-215. 29. Sobel, E.R. and N. Arnaud, A possible middle Paleozoic suture in the Altyn Tagh, NW China. Tectonics, 1999. 18(no.1): p. pp.64-74. 30. Arnaud, N.O. and E.A. Eide, Brecciation-related argon redistribution in alkali feldspars; an in naturo crushing study. Geochimica et Cosmochimica Acta, 2000. 64(no.18): p. pp.3201-3215. 31. Gardien, V., N. Arnaud, and L. Desmurs, Metastability of Precambrian Granulites from the Galicia bank: Consequences of the rheological behaviour of passives margins. Geodynamica Acta, 2000. 13, 103-117. 32. Roger, F., P. Tapponnier, N. Arnaud, U. Schärer, M. Brunel, X. Zhiqin, and Y. Jingsui, An eocene magmatic belt across central Tibet: mantele subduction triggered by the Indian collision ? Terra Nova, 2000. 12: p. 102-108. 33. Adiyaman, O., J. Chorowitz, N.O. Arnaud, M.N. Gündogdu, and A. Gourgaud, Late cenozoic tectonics and volcanism along the north anatolian fault: new structural and geochemical data. Tectonophysics, 2001. 338: p. 135-165. 34. Delville, N., N. Arnaud, J.M. Montel, F. Roger, M. Brunel, P. Tapponnier, and E. Sobel, Paleozoic to Cenozoic deformation along the Altyn-Tagh Fault in the Altun Shan massif area, Eastern Qilian Shan, NE Tibet China. GSA special publication "Paleozoic and Mesozoic tectonic evolution of central Asia: from continental assembly to intracontinental deformation." 2001. 194: p. 269-292. 35. Jolivet, M., M. Brunel, D. Seward, Z. Xu, J. Yang, F. Roger, P. Tapponnier, J. Malavieille, N. Arnaud, and C. Wu, Mesozoic and Cenozoic tectonics of the northern edge of the Tibetan Plateau: fission track constraints. Tectonophysics, 2001. 343: p. 111-134. 36. Leloup, P., N. Arnaud, R. Lacassin, J.R. Kienast, T.m. Harrison, T. Phan Trong, A. Replumaz, and P. Tapponnier, New constraints on the structure, thermochronology and timing of the Ailao Shan-Red River shear zone. J Geophys Res, 2001. 106: p. 6683-6732. 37. Sobel, E.R., N. Arnaud, M. Jolivet, B.D. Ritts, and M. Brunel, Jurassic to Cenozoic exhumation history of the Altyn Tagh range, northwest China, constrained by 40Ar/39Ar and apatite fission track thermochronology. GSA special publication "Paleozoic and Mesozoic tectonic evolution of central Asia -- from continental assembly to intracontinental deformation." 2001. 194: p. 247-267. 38. Tapponnier, P., X. Zhiqin, F. Roger, B. Meyer, N. Arnaud, G. Wittlinger, and Y. Jingsui, Oblique stepwise rise and growth of the Tibet Plateau. Science, 2001. 294(23 november 2001): p. 1671-1677. 39. Huertas, M.J., N.O. Arnaud, E. Ancochea, J.M. Cantagrel, and J.M. Fuster, 40Ar/39Ar stratigraphy of pyroclastic units from the Canadas Volcanic Edifice (Tenerife, Canary Islands) and their bearing on the structural evolution. Journal of Volcanology and Geothermal Research, 2002. 115(3-4): p. 351-365. 40. Arnaud, N., P. Tapponnier, F. Roger, M. Brunel, U. Schärer, Wen C. and Xu ZH. Evidence for Mesozoic shear along the western Kunlun and Altyn-Tagh fault, northern Tibet (China). J Geophys Res-Solid Earth, 2003. doi:10.1029/2002JB002119. 41. Faure, M., Lin Wei, U. Schaerer, L. Shu, L. Sun , and N. Arnaud, Continental subduction and exhumation of UHP rocks. Structural and geochronological insights from the Dabieshan (E. China), 2003, Lithos 70, 213-241 42. Guivel C., Lagabrielle Y., Bourgois J., Martin H., Arnaud N., Fourcade S., Cotten J., and Maury R. C. Very shallow melting of oceanic crust during spreading ridge subduction: Origin of neartrench Quaternary volcanism at the Chile Triple Junction. 2003, J Geophys Res-Solid Earth 108(B3, 2345), doi:10.1029/2002JB002119. 43. Jolivet M., Brunel M., Seward D., Xu Z., Yang J., Malavieille J., Roger F., Leyreloup A., Arnaud N., and Wu C. Neogene Extension and Volcanism in the Kunlun Fault Zone, northern Tibet: New Constraints on the Age of the Kunlun Fault. 2003, Tectonics. 343, 111-134. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. Roger F., Arnaud N. O., Gilder S., Tapponnier P., and Ziqin X. Geochronological and constrains on the Mesozoic evolution of Northern Tibet. 2003 Tectonics Vol. 22(4, 1037), doi: 10, 1029/2002TC001466. Garcia S., Arnaud N. O., Angelier J., Bergerat F., and Homberg C. Rift jump process and new paleorift location in northern Iceland for the last 10 Ma based on 40Ar/39Ar geochronology. 2003, Earth and Planetary Science Letters 214( Issues 3-4), 529-544. Lacassin R., Valli F., Arnaud N., Leloup P. H., Paquette J., Louis, Haibing L., Tapponnier P., Chevalier M. L., Guillot S., Maheo G., and Xu Zhi Q. Large-scale geometry, offset and kinematic evolution of the Karakorum Fault, Tibet. 2004, Earth and Planetary Science Letters 219, 255269, doi:10.1016/S0012-821X(04)00006-8 Maurel, O., J. P. Respaut, P. Monie, N. O. Arnaud and M. Brunel. U–Pb emplacement and 40Ar/39Ar cooling ages of the eastern Mont-Louis granite massif (Eastern Pyrenees, France).2004, C. R. Acad. Sci. Paris 336: 1091-1098. Jolivet. M., Labaume P., Monié P., Brunel M., Arnaud N. O., and Campani M. (2007) Evolution of an intra-continental accretionary prism: insight from the South Pyrenean thrust system (France). Tectonics Sous presse. Karadenizli L., Seyitoglu G., Sen S., Arnaud N. O., Kazanci N., and Alcicek C. (2005) Mammal bearing late Miocene tuffs of the Akkasdagi region; distribution, age, petrographical and geochemical characteristics. Geodiversitas 27, 553-566. Leloup P., Arnaud N., Sobel E. R., and Lacassin R. (2005) Alpine thermal and structural evolution of the highest external crystalline massif: the Mont-Blanc. 2004,. Tectonics 24(doi:10.1029/2004TC001676, 2005). Lin W., Enami M., Faure M., Schärer U., and Arnaud N. (2007) Survival of eclogite xenolith in a Cretaceous granite intruding the Central Dabieshan migmatite gneiss dome (Eastern China) and its tectonic implications. Int J Earth Sci (Geol Rundsch). Maheo G., Valli F., Leloup P. H., Lacassin R., Arnaud N., Paquette J., Louis, Fernandez A., Haibing L., K.A. F., and Tapponnier P. (2007) Post 4 Ma initiation of normal faulting in southern Tibet. Constraints from the Kung Co half-graben. Earth and Planetary Science Letters 256, 233243. Maurel O., Monie P., Pik R., Arnaud N. O., Brunel M., and Jolivet M. (2007) The MesoCenozoic thermo-tectonic evolution of the Eastern Pyrenees: an 40Ar/39Ar fission track and (U– Th)/He thermochronological study of the Canigou and Mont-Louis massifs. Int J Earth Sci (Geol Rundsch). Valli F., Arnaud N. O., Leloup P. H., Sobel E., Maheo G., Lacassin R., Guillot S., Haibing L., Tapponnier P., and Zhiqin X. (in press) 20 million years of continuous deformation along the Karakorum fault, Western Tibet: a thermochronological demonstration. Tectonics. Invited talks 1. Arnaud N. Dept of Earth and Space Sciences, UC. Los Angeles, 1993: “Thermochronology of northern Tibet batholiths”. 2. Arnaud N., 1996 Nordic Geological Survey (NGU), Bohr’s lectures: “Thermochronology: feldspars and beyond” 3. Arnaud N., 2000, Intitute of Geodynamic, Academia Sinica, Beijing: “400 Ma of activity along the Altyn Tagh Fault” 4. Arnaud N., 2004, Intitut für Geowissenschaften, Univ. Podsdam: “Deformation along Northern Tibet since the Proterozoic.” International conferences with proceedings 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. Arnaud , N.O. and K.P.G. Corporate Author Japan, Kagoshima, Japan,. Stromboli; a morphological study 1984-1988. in Kagoshima international conference on Volcanoes 1988. 1988. Kagoshima. Arnaud , N.O., T.M. Harrison, P. Vidal, and Anonymous. Recent developments in thermochronology and some applications to India-Asia collision. in Sixth meeting of the European Union of Geosciences. 1991. Strasbourg. Deng, W.M., N.O. Arnaud , P. Vidal, and Anonymous. Geochemistry and significance of the high K (sub 2) O volcanism of north-western Tibet. in Sixth meeting of the European Union of Geosciences. 1991. Arnaud , N., P. Vidal, and Anonymous. Apports de la geochimie a la connaissance des mecanismes d'accomodation de la collision continentale en Asie. Geochemistry of the mechanisms of continental collision accomodation in Asia. in Programme dynamique et bilans de la Terre; resultats des travaux 1988-1992. Earth dynamics and balances program; research results for 1988-1992. 1992. Paris. Brunel, M., P. Tapponnier, L. Bourjot, N. Arnaud , U. Schaerer, Y. Pan, and Y. Wang. Tectonique de l'Est du Pamir; la traverse de Kashgar-Gungerab. in Programme dynamique et bilans de la Terre; resultats des travaux 1988-1992. 1992. Paris, France: Inst. National Sci. Univers, Centre National. Brunel, M., P. Tapponnier, L. Bourjot, N. Arnaud , U. Schaerer, Y. Pan, Y. Wang, and Anonymous. Tectonique de l'Est du Pamir; la traverse de Kashgar-Gungerab. Tectonics of the eastern Pamirs; the Kashgar-Gungerab traverse. in Programme dynamique et bilans de la Terre; resultats des travaux 1988-1992. Earth dynamics and balances program; research results for 19881992. 1992. Brunel, M., N. Arnaud , P. Tapponnier, P. Vidal, Y. Pan, and Y. Wang. North vergent Nappe Tectonics in the Pamir-Kunlun: preliminary 40Ar/39Ar Jurassic age. in Kashgar International Symposium on Kunlun and Karakorum Mountains. 1992. Brunel, M., P. Tapponnier, L. Bourjot, N. Arnaud , U. Schärer, Y. Pan, and Y. Wang. Tectonics of the Eastern Pamirs. in Kashgar International Symposium on Kunlun and Karakorum Mountains. 1992. Kashgar. Xu, R., Y. Zhang, P. Vidal, and N. Arnaud . Two plutonic belts in Western Kunlun. Transactions du Kashgar. in International Symposium on Kunlun and Karakorum Mountains. 1992. Arnaud , N.O. and Anonymous. Continental escape, crustal thickening and continental subduction; toward a comprehensive model of the India-Asia collision at the lithosphere scale. in Seventh meeting of the European Union of Geosciences; abstract supplement. 1993. Strsbourg. Brunel, M., N. Arnaud , P. Tapponnier, Y. Pan, and Y. Wang. Tectonic denudation at Kongur Shan, mountain building assisted by extension (Karakorum Fault, eastern Pamir). in Late orogenic extension in mountain belts; international meeting. 1993. Paris, France: Bureau de Recherches Geologiques et Minieres, (BRGM). Provost, A., N. Arnaud , and Anonymous. Retrieval of the cooling history and Ar diffusion characteristics of K-feldspars through the global inversion of (super 39) Ar- (super 40) Ar stepheating data. in Seventh meeting of the European Union of Geosciences. 1993. Strasbourg. Tapponnier, P., M. Brunel, L. Bourjot, N. Arnaud , U. Schaerer, Y. Pan, and Y. Wang. Tectonics of the Kongur and Muztagh-Ata ranges, eastern Pamirs. in Seventh meeting of the European Union of Geosciences; abstract supplement. 1993. Oxford, International: Blackwell Scientific Publications. Arnaud , N.O. and S.P. Kelley. Dating of high pressure metamorphism with a new high resolution ultra-violet laser ablation microprobe (super 40) Ar/ (super 39) Ar technique; Dora Maira, western Alps, Italy. in Abstracts of the eighth international conference on Geochronology, 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. cosmochronology, and isotope geology. 1994. Reston, VA, United States: U. S. Geological Survey. Mock, C., N. Arnaud , and J.M. Cantagrel. Thermochronology of 40Ar/39Ar and denudation phenomena in eastern Kunlun, northern Tibet as seen trhough sediments. in 10th Himalaya Karakorum Workshop. 1994. Ascona. Arnaud , N.O. and S.P. Kelley. Argon behaviour in gem-quality orthoclase from Madagascar; experiments and some consequences for 40Ar/ 39Ar geochronology. in AGU 1995 fall meeting. 1995. Washington, DC, United States: American Geophysical Union. Arnaud , N., U. Schaerer, C. Mock, F. Roger, M. Brunel, J. Malavieille, and P. Tapponnier. Age of magmatism and metamorphism of Nortn Eastern Kunlun, China. in 30th Iternational Geological Congress. 1996. Beijing, China. Brunel, M., F. Boudier, J. Malavieille, P. Tapponnier, U. Schaerer, N. Arnaud , Yang Jingsui, Xu Zhiqin, and Anonymous. Caracteristiques des ophiolites des sutures de l'Anyemaqen et du Yangtze. Characteristics of ophiolites of Anyemaqen and Yangtze sutures. in 16>eme) reunion des sciences de la terre; Dynamique et economie Dynamique et economie de la Terre. 16th Earth sciences meeting; Dynamics and economy of the Earth. 1996. Brunel, M., F. Boudier, J. Malavieille, U. Schaerer, N. Arnaud , and P. Tapponnier. Petrographic character of peridotites from the Anemaqen and Yangtse sutures: geodynamic implications. in 30th Iternational Geological Congress. 1996. Beijing, China. Malavieille, J., M. Brunel, Y. Gaudemer, J. van der Woerd, P. Tapponnier, U. Schaerer, J.P. Cogne, J. Marcoux, N. Arnaud , Chen Yan, Xu Zhiqin, and Anonymous. Structure et evolution tectonique de l'Est du Tibet. Structure and tectonic evolution of eastern Tibet. in 16>eme) reunion des sciences de la terre; Dynamique et economie Dynamique et economie de la Terre. 16th Earth sciences meeting; Dynamics and economy of the Earth. 1996. Malavieille, J., M. Brunel, Y. Gaudemer, J. van der Woerd, P. Tapponnier, U. Schaerer, J.P. Cogné, J. Marcoux, N. Arnaud , and C. Yan. Structure and tectonic evolution of eastern Tibet: results of the 1993-1994 geotraverses. in 30th Iternational Geological Congress. 1996. Beijing, China. Mock, C., N. Arnaud , and Anonymous. Thermochronologie 40Ar/39Ar et phenomenes de denudation dans l'Est du Kunlun (Nord Tibet). Thermochronology of 40Ar/39Ar and denudation phenomena in eastern Kunlun, northern Tibet. in 16>eme) reunion des sciences de la terre; Dynamique et economie Dynamique et economie de la Terre. 16th Earth sciences meeting; Dynamics and economy of the Earth. 1996. Orléans. Sobel, E.R., N. Arnaud , and Anonymous. Age controls on origin and cooling of the Altyn Tagh Range, NW China. in Geological Society of America, 28th annual meeting. 1996. Arnaud , N.O., M. Brunel, F. Roger, U. Schärer, J. Malavieille, . , and P. TAPPONNIER. Age,duration and thermal conditions associated with major strike-slip faults: examples from northern Tibet. in European Union of Geosciences conference 9. 1997. Sobel, E. and N. Arnaud . The Paleozoic Altyn Tagh: a comparison with adjacent orogens. in 12th Himalaya Karakorum Workshop. 1997. Rome. Arnaud , N. and E.A. Eide. Brecciation related argon redistribution in K-feldspars: an in naturo crushing study. in Abstracts of the International Conference on Geochronology, Cosmochronology, and Isotope Geology. 1998. Toulouse. Arnaud , N., N. Delville, J.M. Montel, F. Roger, M. Brunel, P. Tapponnier, and E. Sobel. Paleozoic to Cenozoic deformation along the Altyn Tagh Fault in the Altun Shan massif area, Eastern Qilian Shan, NE Tibet China. in AGU 1999 fall meeting. 1999. San Francisco: Washington, DC, United States. Arnaud , N. and E. Sobel. Cretaceous - Paleogene basaltic rocks of the Tuyon basin, NW China and the Kyrgyz Tian Shan: the trace of a small plume ? in 14th Himalayan Karakorum Workshop. 1999. Kloster Ettal, Germany. 29. Arnaud , N., U. Schaerer, C. Mock, F. Roger, M. Brunel, J. Malavieille, and P. Tapponnier. Ages of magmatism and tectonism of North-Eastern Kunlun, China. in 30th International Geological Congress. 1999. Beijing. 30. Bourgois, J., Y. Lagabrielle, R.C. Maury, C. Guivel, N. Arnaud , H. Martin, and T. Calmus. Two phases of ophiolite emplacement at the Chile margin triple junction area (46-47S). in AGU 1999 fall meeting. 1999. San Francisco: Washington, DC, United States. 31. Brunel, M., F. Boudier, J. Malavieille, U. Schaerer, N. Arnaud , and P. Tapponnier. Petrographic character of peridotites from the Anemaqen and Yangtze sutures: geodynamic implications. in 30th International Geological Congress. 1999. Beijing. 32. Crambes, C., S.R. Tait, P. Tapponnier, N. Arnaud , and F.J. Ryerson. Post-collision volcanic rocks from the Kokoshili Shan, northeastern Tibetan Plateau; mafic to acidic young volcanism. in European Union of Geosciences conference 10. 1999. 33. Lacassin, R., P.H. Leloup, P. Tapponnier, S. Bergman, N. Arnaud , and A. Replumaz. Deformation and Cooling Diachronism Along the Sagaing Fault and Shan Escarpment. in European Union of Geosciences conference 10. 1999. 34. Malavieille, J., M. Brunel, Y. Gaudemer, J. van der Woerd, P. Tapponnier, U. Schaerer, J.P. Cogné, J. Marcoux, N. Arnaud , and C. Yan. Structure and tectonic evolution of eastern Tibet: results of the 1993-1994 geotraverses. in 30th International Geological Congress. 1999. Beijing. 35. Hammouda, T. and N. Arnaud . Argon diffusion in synthetic F-Phlogopite: implications for thermochronology and argon recoil. in EGS meeting, 26th assembly. 2001. Nice: European Geophysical Society. 36. Arnaud , N., N. Agranier, G. Chazot, C. Pin, J.L. Poidevin, and J. Blichert-Toft. High-K magmas from the French Massif Central: crust-mantle interaction during the Hercynian orogeny. in Goldschmidt Conference. 2002. Davos, Switzerland. 37. Garcia, S., N. Arnaud , J. Angelier, F. Bergerat, and C. Homberg. Radiometric-based discovery of a paleo-rift: the Skagafjordur paleo-rift, and tectonic reorganisation of northern Iceland since 8 My. in EGS meeting, 27th assembly. 2002. Nice: European Geophysical Society. 38. Leloup, P.H., N. Arnaud , R. Lacassin, F. Masson, and F. Gal. Structures alpines responsables de l'exhumation du massif du Mt Blanc. in Réunion des Sciences de la Terre, RST2002. 2002. Nantes. 39. Arnaud , N.O., J.L. Paquette, P.H. Leloup, F. Valli, S. Guillot, H. Li, X. Zhiqin, R. Lacassin, and P. Tapponnier. Cretaceous magmatism and deformation in central-west Tibet. in EGS meeting, 27th assembly. 2003. Nice: Geophysical Research Abstracts. 40. Arnaud , N.O., S. Garcia, and F. Bergerat. Precise 40Ar/39Ar dating of basaltic dykes as an indicator of paleostress: exemple of the Icelandic rift jumps. in EGS meeting, 27th assembly. 2003. Nice: Geophysical Research Abstracts. 41. Lacassin R., Valli F., Arnaud N., Leloup P. H., Guillot S., Paquette J. L., Tapponnier P., Li H., and Zhiqin X. (2003) Large-scale geometry, offset and kinematic evolution of the Karakorum Fault, Tibet. EGS meeting, 27th assembly. 42. Leloup P. H., Valli F., Lacassin R., Arnaud N., Paquette J. L., Guillot S., Tapponnier P., Li H., and Zhiqin X. (2003) Evidence for tertiary high temperature dextral shear along the karakorum fault zone. EGS meeting, 27th assembly. 43. Maheo G., Guillot S., Arnaud N., Farley K., and Pêcher A. (2003) Two stages of exhumation of the south Karakorum migmatites revealed by Ar/Ar and (U-Th)/He dating. EGS meeting, 27th assembly. 44. Valli F., Arnaud N., Lacassin R., Paquette J. L., Leloup P. H., Li H., Tapponnier P., Guillot S., Deloule E., Maheo G., and Zhiqin X. (2003) New age constraints on the evolution of the Karakorum Fault, West Tibet. AGU Fall Meeting. 45. Arnaud N. O. (2003) 400 My of Deformation Along Tibet Active Strike Slip Faults. AGU Fall meeting. Popular Science 1. Arnaud , N., La mémoire des reliefs disparus., in La Recherche. 1998. 2. Arnaud , N.O., Les méthodes K/Ar et 40Ar/39Ar: principes et application à la géochronologie archéologique., in L'obsidienne au Proche et au Moyen Orient: du volcan à l'outil, B.G. A. Gourgaud, G. Poupeau,JL. Poidevin et M.C. Cauvin (Editeurs),, Editor. 1998, ArcheoPress: Oxford. 3. Gerbe, M.C., H. Gonord, and N.O. Arnaud , Stratigraphie et âge des formations de bordure du fossé du Forez. Géologie de la France, 1998. 2: p. 47-53. 4. Arnaud , N., La notion d'âge en géochronologie 40Ar/39Ar: méthodologie et applications., in Département de Géologie. 2001, Blaise Pascal, Clermont 2: Clermont-Ferrand. p. 100. 5. Arnaud , N.O. and P. Vidal, Le volcanisme du plateau tibétain, une fenêtre ouverte sur le manteau, in Himalaya-Tibet, le choc des continents, J.P. Avouac and P. de Wever, Editors. 2003, Muséum National d'Histoire Naturelle Centre National de la Recherche Scientifique: Paris. p. 100105. Other Papers 1. Arnaud , N.O., Apports de la thermochronologie 40Ar/ 39Ar sur feldspath potassique a la connaissance de la tectonique cenozoique d'Asie; etude des mecanismes d'accomodation de la collision continentale, in Département de Géologie. 1992, Clermont-Ferrand 2, Blaise Pascal: Clermont-Ferrand, France. p. 161. 2. Chen Wen, Li Haibing, Xu Zhiqin, N. Arnaud , Han Dan, and Shen Jie, Using the laser microprobe (super 40) Ar/ (super 39) Ar dating techniques and the (super 40) Ar/ (super 39) Ar stepwise incremental heating technique to date the ages of Xidatan shear zone. Diqiu Xuebao = Acta Geoscientia Sinica, 1996. 17(Special issue): p. pp.228-232. 3. Chen Wen and N. Arnaud , Isotope geochronology study for "POG type" granite in Bayan Har Terrain, Qinghai-Xizang Plateau, China. Diqiu Xuebao = Acta Geoscientia Sinica, 1997. 18(no.3): p. pp.261-266.