Fluid emission along the Nankai Trough

Our most recent publication is now available on-line!

  • Tomonaga, Y., Yagasaki, K., Park, J.-O., Ashi, J., Toyoda, S., Takahata, N., & Sano, Y. (2020). Fluid emission along the Nankai Trough: He isotopes reveal direct seafloor mantle-fluid emission in the Kumano Basin (southwest Japan), ACS Earth Space Chem., doi:10.1021/acsearthspacechem.0c00229.

The work is directly related to the NoGOS project and the time I enjoyed working in the Marine Analytical Chemistry group at the Atmosphere and Ocean Research Institute (AORI) of the University of Tokyo.

Recent publications

Following articles have been accepted for publication in peer-reviewed journals:

  • Tyroller, L., Brennwald, M. S., Tomonaga, Y., Maden, C., & Kipfer, R. (2020). Noble gases as tracers for the gas dynamics in methane supersaturated lacustrine sediments. Chem. Geol., in press, doi: 10.1016/j.chemgeo.2020.119905.
  • Brennwald, M. S., Tomonaga, Y., & Kipfer, R. (2020). Deconvolution and compensation of mass spectrometric overlap interferences with the miniRUEDI portable mass spectrometer. MethodsX, 7, 101038, doi: 10.1016/j.mex.2020.101038.

Formation and migration of hydrocarbons in deeply buried sediments of the Gulf of Cadiz convergent plate boundary

The following co-authored article has been published in Marine Geology:

  • Nuzzo, M., Tomonaga, Y., Schmidt, M., Valadares, V., Faber, E., Piñero, E., Reitz, A., Haeckel, M., Tyroller, L., Godinho, E., Kipfer, R., Terrinha, P.G., & Hensen, C. (2019). Formation and migration of hydrocarbons in deeply buried sediments of the Gulf of Cadiz convergent plate boundary – Insights from the hydrocarbon and helium isotope geochemistry of mud volcano fluids. Mar. Geol.,410, 56–69 doi:10.1016/j.margeo.2019.01.005.

Highlights:

  • Clay dehydration water expelled from buried sediments drives mud volcanism.
  • Rise of fluids mediated by crustal-scale strike-slip faults cross-cutting wedge.
  • On active accretionary wedge, petroleum accumulations were dismantled in Neogene.
  • 4He enrichment and δ13C-CH4 ~−50‰ in fluids reflect an open hydrocarbon system.
  • Petroleum pools remain on shallow margin. Microbial gas vented out of active wedge.

Here you can download the manuscript for free until March 13th, 2019.