Institutional development · Research, innovation and assessment · Japan
Seafloor spreading does not necessarily start hot, Kyoto University Okinawa Trough study finds
Researchers from Kyoto University and Japan's National Institute of Advanced Industrial Science and Technology report that rifts in the southern Okinawa Trough can form through normal faulting under low heat flow.
Why it matters: Marine geology and geophysics researchers studying crust formation in subduction zones have new heat flow and seismic data from the southern Okinawa Trough.
A team including Makoto Otsubo of the National Institute of Advanced Industrial Science and Technology (AIST) and Kyoto University's Daisuke Kuwano and Seiya Fujishima carried out reflection seismic surveys and crustal heat flow measurements in the Yaeyama and Yonaguni grabens of the southern Okinawa Trough, the university said.
According to Kyoto University, the team found that widespread normal faulting can create rift topography even when the crust is cool and heat flow is low.
The university said the results suggest seafloor spreading may advance with limited evidence of regional magma supply, although local magmatic activity is possible.
The study was published on 21 October 2026 in the journal Progress in Earth and Planetary Science.
Editor’s view
Scott James, Research and Innovation Editor
The findings concern researchers working on crust formation in plate subduction zones, and the university said further research, including deep-sea scientific drilling, is anticipated.
