Researcher Information

Marie Python

Assistant Professor

What is at the bottom of the oceans ?

Department of Earth and Planetary Sciences, Earth and Planetary System Science

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Theme

Understanding how the ocean lithosphere form based on field and sample observations and analyses

FieldOcean geology, Petrology, Geochemistry
KeywordOcean floor, Ocean lithosphere, Ocean hydrothermalism, Ocean magmatism, Ophiolites, Earth mantle, Peridotites, Gabbros

Introduction of Research

By investigating the mantle and crustal sections in ophiolites in parallel to hard rock cores drilled in present days oceans, we aim to elucidate the various processes leading to the formation and transformation of the oceanic lithosphere. Rocks drilled at East Pacific Rise during IODP Exp. 345 (on Joides Resolution, see photo 1 and 2) are used to investigate magmatic and hydrothermal processes occurring in the lower oceanic crust. The Oman ophiolite (Photos 3 and 4) is the biggest and best exposed ophiolite in the world. It is interpreted as being a remnant of oceanic lithosphere from Tethys which was obducted onto the Arabian margin. Field investigations in the Oman ophiolite allowed me to observe ocean lithosphere structures (Photos 5 and 6) and to locate any sample taken in its context. My researches are focussing on the various magmatic and hydrothermal processes occurring in the oceanic mantle and gabbroic crust. My main results showed that at the scale of the Oman ophiolite several mantle source can be observed and that magmatic processes occurring in the deep crust (fractional crystallisation, melt-rock reaction, mixing of various sources, etc.) have a strong effect on the composition of the magma erupted at the surface.

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Drilling ship Joides Resolution leaving port (credit : Bill Crawford, IODP)
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4 scientists holding a freshly drilled core from the East Pacific Rise (credit : Bill Crawford, IODP)
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Map of the Eurasian continent showing Oman location
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Landsat photo of the northern Arabian Peninsula showing contrasting rock formations: grey-yellow zones show sand deserts and sedimentary rocks; dark formation represent the ophiolite
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Pillow lava as seen in the Oman ophiolite
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The mantle-crust transition can be observed in the landscape in the Oman ophiolite

Representative Achievements

Masako Yoshikawa, Marie Python, Akihiro Tamura, Shoji Arai, Eiichi Takazawa, Tomoyuki Shibata, Akira Ueda and Tsutomu Sato. Melt extraction and metasomatism recorded in basal lherzolites above metamorphic sole from the northern Fizh massif, the Oman ophiolite. Tectonophysics, 650, 53-64, 2015.
Kathryn M. Gillis, Jonathan E. Snow, Adam Klaus, Marie Python, Natsue Abe, Álden de Brito Adrião, Norikatsu Akizawa, Georges Ceuleneer, Michael J. Cheadle, Kathrin Faak, Trevor J. Falloon, Sarah A. Friedman, Marguerite M. Godard, Gilles Guerin, Yumiko Harigane, Andrew J. Horst, Takashi Hoshide, Benoit Ildefonse, Marlon M. Jean, Barbara E. John, Juergen Koepke, Sumiaki Machi, Jinichiro Maeda, Naomi E. Marks, Andrew M. McCaig, Romain Meyer, Antony Morris, Toshio Nozaka, Abhishek Saha and Robert P. Wintsch. Primitive Layered Gabbros from Fast-Spreading Lower Oceanic Crust. Nature, 505, 204-207, 2014.
Marie Python, Masako Yoshikawa, Tomoyuki Shibata and Shoji Arai. Diopsidites and rodingites in the Oman ophiolite mantle: serpentinisation and Ca-metasomatism. In Dyke Swarms: Keys for Geodynamic Interpretation, Rajesh K. Srivastava ed., Springer-Verlag, Heidelberg, 401-435, 2011.
Marie Python, Georges Ceuleneer and Shoji Arai. Chromian spinels in mafic-ultramafic mantle dykes: evidence for two-stage melt production during the evolution of the Oman ophiolite. Lithos, 106, 137-154, 2008.
Marie Python, Georges Ceuleneer, Yoshito Ishida, Jean-Alix Barrat and Shoji Arai. Oman diopsidites: a new lithology diagnostic of very high temperature hydrothermal circulation in mantle peridotite below oceanic spreading centres. Earth & Planetary Science Letters, 255, 289-305, 2007.
Academic degreePhD
Self Introduction

I was raised at thte bottom of the Alps in Europe and I sent most of my school holidays near the Atlantic coast at my grand parents place. As a consequence, as a child already, I felt in love with mountains and oceans and having a job which allows me to spend time on the oceans and in the mountains is a real happiness.

Academic background2002 PhD graducation at Université Paul Sabatier, Toulouse (France)
2002 Post-doctorate at Université Paul sabatier, Toulouse (France)
2004 JSPS then Inoue fundation fellow post-doctorate at Kanazawa University (Japan)
2008 Post-doctoral fellow at Kyoto University’s Institute for Geothermal Sciences, Beppu (Japan)
2010 to present Assistant professor at Hokkaido Uniersity (Japan)
Affiliated academic societyJapan geological society, Japan Geoscience union, European Geoscience union
ProjectOman drilling project
IODP
Room address理学部6号館 6-10-03号室

Department of Earth and Planetary Sciences, Earth and Planetary System Science

Marie Python

Assistant Professor

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Please briefly introduce us to the big project you have been tackling.

The “mohole” or project to drill the Earth mantle started as about the same time as the spacial project aiming to reach the moon. People walked on the moon after in 20 years but after 70 years, we still do not know what are the rocks forming the deep layers of the earth crust and the upper mantle.

As the oceanic crust is thinner than the continental crust, the project was focussed on drilling oceanic crust down to the mantle. Drilling ships able to recover rocks from deep oceans were developed and constructed but as interest for science slow down these last 30 years, and governments motivation for big scientific projects disappear, funding is now insufficient to maintain and achieve this project

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What made you decide to become a researcher?

Since my childhood, I have been really curious of everything, bothering my mother continuously asking question about anything and trying to understand how things work as much as possible. Later, when studying maths and science at school, I found a strong interest for science. Up to now I really like how the scientific method helps for understanding various things.

As I always loved mountain, nature and outdoor activities, turning to geology felt completely natural during my studies. But in all possible applications of geology, only research could satisfy my insatiable curiosity.

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Please tell us about yourself; things you are good at, your favorites, hobbies, and daily routines.

I have quite a lot of centres of interest, but what I like the most is spending time outside in nature. In my work, field work is definitively my favourite thing, and I also spend my free time biking, skiing, rock or ice climbing, hiking etc.

Out of outdoor activities, I like reading books, cooking, and cuddle my cat.