Influence of outer-rise faults on shallow décollement heterogeneity and sediment flux at the Japan trench


  • Emily Schottenfels School of Earth and Sustainability, Northern Arizona University
  • Christine Regalla School of Earth and Sustainability, Northern Arizona University
  • Yasuyuki Nakamura Japan Agency for Marine-Earth Science and Technology (JAMSTEC)



We investigate the impact of outer-rise normal fault subduction on the structural evolution of the décollement and frontal prism in a portion of the Japan trench that hosted the 2011 Tohoku earthquake. We use seismic reflection data to map the relative occurrence of sediment accretion, sediment subduction, and frontal tectonic erosion in the shallow portion of the subduction zone and correlate these deformation styles to the magnitude of outer-rise fault throw and incoming plate sediment thickness. These data reveal spatial heterogeneity in the modes of deformation over distances of 5-10 km that necessitate correlative heterogeneity in the geometry and composition of the shallow décollement over similar length-scales. We find that sediment accretion predominantly occurs in regions where incoming plate sediment thickness is greater than fault throw. In these areas, the décollement appears to be non-planar and compositionally homogenous. Conversely, frontal tectonic erosion and slope failures are predominantly observed in regions where fault throw is greater than sediment thickness. In these areas, the décollement may be planar but compositionally heterogeneous. Additionally, spatial variations in near trench slip appear to correlate with the dominant deformation modes, suggesting that both sediment thickness and outer-rise fault throw may be important controls on shallow megathrust behavior.


Boston, B., Moore, G. F., Nakamura, Y., & Kodaira, S. (2014). Outer-rise normal fault development and influence on near-trench décollement propagation along the Japan Trench, off Tohoku. Earth, Planets and Space, 66(1), 135.

Chester, F. M., & Moore, J. C. (2018). Tectonostratigraphy and processes of frontal accretion with horst-graben subduction at the Japan Trench. In Geology and Tectonics of Subduction Zones: A Tribute to Gaku Kimura. Geological Society of America.

Chester, F. M., Rowe, C., Ujiie, K., Kirkpatrick, J., Regalla, C., Remitti, F., Moore, J. C., Toy, V., Wolfson-Schwehr, M., Bose, S., Kameda, J., Mori, J. J., Brodsky, E. E., Eguchi, N., & Toczko, S. (2013). Structure and Composition of the Plate-Boundary Slip Zone for the 2011 Tohoku-Oki Earthquake. Science, 342(6163), 1208–1211.

Clift, P., & Vannucchi, P. (2004). Controls on tectonic accretion versus erosion in subduction zones: Implications for the origin and recycling of the continental crust. Reviews of Geophysics, 42(2).

Contreras‐Reyes, E., Grevemeyer, I., Flueh, E. R., Scherwath, M., & Heesemann, M. (2007). Alteration of the subducting oceanic lithosphere at the southern central Chile trench–outer rise. Geochemistry, Geophysics, Geosystems, 8(7).

Fujie, G., Kodaira, S., Nakamura, Y., Morgan, J. P., Dannowski, A., Thorwart, M., Grevemeyer, I., & Miura, S. (2020). Spatial variations of incoming sediments at the northeastern Japan arc and their implications for megathrust earthquakes. Geology, 48(6), 614–619.

Fujiwara, T., Hirano, N., Abe, N., & Takizawa, K. (2007). Subsurface structure of the “petit‐spot” volcanoes on the northwestern Pacific Plate. Geophysical Research Letters, 34(13).

Fulton, P. M., Brodsky, E. E., Kano, Y., Mori, J., Chester, F., Ishikawa, T., Harris, R. N., Lin, W., Eguchi, N., & Toczko, S. (2013). Low Coseismic Friction on the Tohoku-Oki Fault Determined from Temperature Measurements. Science, 342(6163), 1214–1217.

Hilde, T. W. C. (1983). Sediment subduction versus accretion around the pacific. Tectonophysics, 99(2–4), 381–397.

Hirano, N., Machida, S., Sumino, H., Shimizu, K., Tamura, A., Morishita, T., Iwano, H., Sakata, S., Ishii, T., Arai, S., Yoneda, S., Danhara, T., & Hirata, T. (2019). Petit-spot volcanoes on the oldest portion of the Pacific plate. Deep Sea Research Part I: Oceanographic Research Papers, 154, 103142.

Hirano, N., Takahashi, E., Yamamoto, J., Abe, N., Ingle, S. P., Kaneoka, I., Hirata, T., Kimura, J.-I., Ishii, T., Ogawa, Y., Machida, S., & Suyehiro, K. (2006). Volcanism in Response to Plate Flexure. Science, 313(5792), 1426–1428.

Iinuma, T., Hino, R., Kido, M., Inazu, D., Osada, Y., Ito, Y., Ohzono, M., Tsushima, H., Suzuki, S., Fujimoto, H., & Miura, S. (2012). Coseismic slip distribution of the 2011 off the Pacific Coast of Tohoku Earthquake (M9.0) refined by means of seafloor geodetic data. Journal of Geophysical Research: Solid Earth, 117(B7).

Ikari, M. J., Kameda, J., Saffer, D. M., & Kopf, A. J. (2015). Strength characteristics of Japan Trench borehole samples in the high-slip region of the 2011 Tohoku-Oki earthquake. Earth and Planetary Science Letters, 412, 35–41.

Ikehara, K., Usami, K., Kanamatsu, T., Arai, K., Yamaguchi, A., & Fukuchi, R. (2017). Spatial variability in sediment lithology and sedimentary processes along the Japan Trench: use of deep-sea turbidite records to reconstruct past large earthquakes. Geological Society, London, Special Publications, 456(1), 75–89.

Kameda, J., Shimizu, M., Ujiie, K., Hirose, T., Ikari, M., Mori, J., Oohashi, K., & Kimura, G. (2015). Pelagic smectite as an important factor in tsunamigenic slip along the Japan Trench. Geology, 43(2), 155–158.

Kirkpatrick, J. D., Rowe, C. D., Ujiie, K., Moore, J. C., Regalla, C., Remitti, F., Toy, V., Wolfson-Schwehr, M., Kameda, J., Bose, S., & Chester, F. M. (2015). Structure and lithology of the Japan Trench subduction plate boundary fault. Tectonics, 34(1), 53–69.

Kodaira, S., Fujiwara, T., Fujie, G., Nakamura, Y., & Kanamatsu, T. (2020). Large Coseismic Slip to the Trench During the 2011 Tohoku-Oki Earthquake. Annual Review of Earth and Planetary Sciences, 48(1), 321–343.

Kodaira, S., Nakamura, Y., Fujie, G., & Miura, S. (2019). Marine active‐source seismic studies in the Japan Trench: a seismogenic zone in an ocean‐continent collision zone. Acta Geologica Sinica - English Edition, 93(S1), 94–95.

Kodaira, S., Nakamura, Y., Yamamoto, Y., Obana, K., Fujie, G., No, T., Kaiho, Y., Sato, T., & Miura, S. (2017). Depth-varying structural characters in the rupture zone of the 2011 Tohoku-oki earthquake. Geosphere, 13(5), 1408–1424.

Kodaira, S., No, T., Nakamura, Y., Fujiwara, T., Kaiho, Y., Miura, S., Takahashi, N., Kaneda, Y., & Taira, A. (2012). Coseismic fault rupture at the trench axis during the 2011 Tohoku-oki earthquake. Nature Geoscience, 5(9), 646–650.

Masson, D. G. (1991). Fault patterns at outer trench walls. Marine Geophysical Researches, 13(3), 209–225.

Moore, G. F., Shipley, T. H., & Lonsdale, P. F. (1986). Subduction erosion versus sediment offscraping at the toe of the Middle America Trench off Guatemala. Tectonics, 5(4), 513–523.

Moore, J. C., Plank, T. A., Chester, F. M., Polissar, P. J., & Savage, H. M. (2015). Sediment provenance and controls on slip propagation: Lessons learned from the 2011 Tohoku and other great earthquakes of the subducting northwest Pacific plate. Geosphere, 11(3), 533–541.

Morgan, J. K., Ramsey, E. B., & Ask, M. V. S. (2007). 8. Deformation and Mechanical Strength of Sediments at the Nankai Subduction Zone: Implications for Prism Evolution and Décollement Initiation and Propagation. In The Seismogenic Zone of Subduction Thrust Faults (pp. 210–256). Columbia University Press.

Nakamura, Y., Fujiwara, T., Kodaira, S., Miura, S., & Obana, K. (2020). Correlation of frontal prism structures and slope failures near the trench axis with shallow megathrust slip at the Japan Trench. Scientific Reports, 10(1).

Nakamura, Y., Kodaira, S., Fujie, G., Yamashita, M., Obana, K., & Miura, S. (2023). Incoming plate structure at the Japan Trench subduction zone revealed in densely spaced reflection seismic profiles. Progress in Earth and Planetary Science, 10(1).

Nakamura, Y., Kodaira, S., Miura, S., Regalla, C., & Takahashi, N. (2013). High‐resolution seismic imaging in the Japan Trench axis area off Miyagi, northeastern Japan. Geophysical Research Letters, 40(9), 1713–1718.

Nasu, N., von Huene, R., Ishiwada, Y., Langseth, L., Bruns, T., & Honza, E. (1980). Interpretation of Multichannel Seismic Reflection Data, Legs 56 and 57, Japan Trench Transect, Deep Sea Drilling Project. In Initial Reports of the Deep Sea Drilling Project, 56/57. U.S. Government Printing Office.

Nishikawa, T., Ide, S., & Nishimura, T. (2023). A review on slow earthquakes in the Japan Trench. Progress in Earth and Planetary Science, 10(1).

Polet, J., & Kanamori, H. (2000). Shallow subduction zone earthquakes and their tsunamigenic potential. Geophysical Journal International, 142(3), 684–702.

Qin, Y., Nakamura, Y., Kodaira, S., & Fujie, G. (2022). Seismic imaging of subsurface structural variations along the Japan trench south of the 2011 Tohoku earthquake rupture zone. Earth and Planetary Science Letters, 594, 117707.

Regalla, C., Bierman, P., & Rood, D. H. (2019). Meteoric 10Be Reveals a Young, Active Accretionary Prism and Structurally Complex Décollement in the Vicinity of the 2011 Tohoku Earthquake Rupture. Geochemistry, Geophysics, Geosystems, 20(11), 4956–4971.

Saffer, D. M., & Tobin, H. J. (2011). Hydrogeology and Mechanics of Subduction Zone Forearcs: Fluid Flow and Pore Pressure. Annual Review of Earth and Planetary Sciences, 39(1), 157–186.

Sawai, M., Niemeijer, A. R., Hirose, T., & Spiers, C. J. (2017). Frictional properties of JFAST core samples and implications for slow earthquakes at the Tohoku subduction zone. Geophysical Research Letters, 44(17), 8822–8831.

Schottenfels, E., Regalla, C., & Nakamura, Y. (2023). Influence of outer-rise faults on sediment flux and décollement heterogeneity at the Japan trench.

Seno, T., Stein, S., & Gripp, A. E. (1993). A model for the motion of the Philippine Sea Plate consistent with NUVEL‐1 and geological data. Journal of Geophysical Research: Solid Earth, 98(B10), 17941–17948.

Shipboard Scientific Party. (1980). Site 436, Japan Trench Outer Rise, Leg 56. In Initial Reports of the Deep Sea Drilling Project, 56/57. U.S. Government Printing Office.

Strasser, M., Kölling, M., Ferreira, C. dos S., Fink, H. G., Fujiwara, T., Henkel, S., Ikehara, K., Kanamatsu, T., Kawamura, K., Kodaira, S., Römer, M., & Wefer, G. (2013). A slump in the trench: Tracking the impact of the 2011 Tohoku-Oki earthquake. Geology, 41(8), 935–938.

Sun, T., Saffer, D., & Ellis, S. (2020). Mechanical and hydrological effects of seamount subduction on megathrust stress and slip. Nature Geoscience, 13(3), 249–255.

Tanioka, Y., Ruff, L., & Satake, K. (1997). What controls the lateral variation of large earthquake occurrence along the Japan Trench? Island Arc, 6(3), 261–266.

Tsuru, T., Park, J., Miura, S., Kodaira, S., Kido, Y., & Hayashi, T. (2002). Along‐arc structural variation of the plate boundary at the Japan Trench margin: Implication of interplate coupling. Journal of Geophysical Research: Solid Earth, 107(B12).

Tsuru, T., Park, J., Takahashi, N., Kodaira, S., Kido, Y., Kaneda, Y., & Kono, Y. (2000). Tectonic features of the Japan Trench convergent margin off Sanriku, northeastern Japan, revealed by multichannel seismic reflection data. Journal of Geophysical Research: Solid Earth, 105(B7), 16403–16413.

von Huene, R., & Culotta, R. (1989). Tectonic erosion at the front of the Japan Trench convergent margin. Tectonophysics, 160(1–4), 75–90.

von Huene, R., & Lallemand, S. (1990). Tectonic erosion along the Japan and Peru convergent margins. Geological Society of America Bulletin, 102(6), 704–720.<0704:teatja>;2

von Huene, R., Langseth, M., Nasu, N., & Okada, H. (1982). A summary of Cenozoic tectonic history along the IPOD Japan Trench transect. Geological Society of America Bulletin, 93(9), 829.<829:asocth>;2

Wang, K., & Bilek, S. L. (2014). Invited review paper: Fault creep caused by subduction of rough seafloor relief. Tectonophysics, 610, 1–24.

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How to Cite

Schottenfels, E., Regalla, C., & Nakamura, Y. (2024). Influence of outer-rise faults on shallow décollement heterogeneity and sediment flux at the Japan trench. Seismica, 3(1).




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