Webmaster : Francois Lacan

Francois Lacan

Chargé de Recherche, CNRS

Researcher at CNRS

LEGOS, Laboratoire d'Etude en Géophysique et Océanographie Spatiales
14 av. Edouard Belin, 31400 Toulouse, France

Marine Geochemistry group

Phone : +33 5 61 33 30 43 - Fax. +33 5 61 25 32 05

List of Communications

Background and mobility
• Since 2005 : LEGOS, Toulouse, France. Assistant Scientist

• 2005 : LSCE, Gif-sur-Yvette, France. Postdoc

• 2003-2004 -: WHOI, Woods Hole, USA. Postdoc

• 1999-2002 -: LEGOS, Toulouse, France. PhD

Scientific Interests

Geochemistry applied to matter fluxes and water mass transports in the modern ocean.

• Iron isotopes: origins of iron inputs to the ocean, role of the margins in the iron oceanic cycle.

• Neodymium isotopes: water mass circulation and mixing, terrigeneous inputs, dissolved-particulate exchanges.

• Thorium and Protactinium isotopes: deep water ventilation, scavenging, particulate fluxes.

• Cadmium isotopes: primary production, carbon fluxes, deep water ventilation.

Multi-tracer approach. Hydrology. Modelling of geochemical tracers. Paleoceanography proxy calibration.

Skills
• Trace element chemistry (notably in seawater). Preconcentration, purification (liquid chromatography), mineralization (notably microwave);

• Mass spectrometry :Thermo Ionization (Thermo Finnigan MAT 261), Inductively Coupled Plasma: single collection (Perkin-Elmer ELAN 6000, Thermo Finnigan Element II) and multi collection (Thermo Finnigan Neptune), isotopic dilutions, double spiking, interference corrections, sensitivity corrections, mass bias corrections;

• Atomic Absorption;

• Seawater sampling (in situ pumps...);

• Core sampling. Pore water sampling.

Experience at Sea

• BONUS-GOODHOPE : R/V Marion Dufresne, IPEV, Feb. Mar. 2008, South Africa - Southern Ocean. In charge of Nd, Pa, Th and Fe isotopes sampling.

• EUCFe - ISOFERIX : R/V Kilo Moana, Univ of Hawaii, Sept. Oct. 2006, Hawaii - Papua New Guinea. In charge of Nd and Fe isotopes sampling.

• TIP2000 : (R/V Marion Dufresne, IFRTP, France, septembre 2000, Indonesia - Australia. In charge of Nd and Th isotopes sampling.

Projects

• SOLWARA (INSU, PI. S. Cravatte, LEGOS). 2008-2010. Physical and geochemical transformations within the Salomon Sea.

• GEOCAL (INSU, PI. F. Lacan, LEGOS). 2008-2010. A French contribution to the GEOTRACES intercalibration effort (Fe, Nd and Ra isotopes, ²³¹Pa, ²³⁰Th)

• BONUS-GOODHOPE (LEFE, ANR, PIs M. Boyé LEMAR, S. Speich LPO). 2007-2012. Interactions between the dynamic, circulation, biogeochemistry and geochemistry in the Atlantic sector of the Southern Ocean and its exchanges with the Indo-Atlantic connection.

• ISOFERIX (INSU, PI. F. Lacan, LEGOS). 2006-2008. ISOtopic tracing of Fe sources in the Equatorial Pacific: impact on new primary production and nitRogen fIXation (EUCFE cruise)

• AMANDES (ANR, PI. C. Jeandel, LEGOS). 2006-2008. Weathering and transport of elements at a crucial land-sea interface (Amazone estuary)

• KEOPS (INSU, PI. S. Blain. LOB). 2005-2007. KErguelen :compared study of the Ocean and the Plateau in Surface water

• MOZAIQUE (INSU, PI. J-C Dutay, LSCE). 2006-2009. Modeling of trace elements in the ocean: Neodymium (Nd), Protactinium (Pa) and Thorium (Th)

• OceanicCdIC (WHOI, PI. R. Francois). 2003. Cadmium isotopic composition in the ocean

• SIGNATURE/GINS (INSU, PI C. Jeandel, LEGOS). 1999-2002. Neodymium isotopic composition in the North Atlantic