Mass transport‐dominated sedimentation in a foreland basin, the Hidaka Trough, northern Japan

Abstract

[1] Mass transport is an important process of sediment redistribution from shallow to deep sea basins. It is vital to understand this process for disaster prevention and protection of economic interests in coastal and offshore areas. We describe mass transport-dominated sedimentation in an active foreland basin, the Hidaka Trough, which developed from collision between the northeastern Japan arc and the Kuril arc. The basin is deformed by east-west compression associated with large, frequent earthquakes. The trough is filled with thick (>4.5 km) sediments, ranging from coal-bearing Cretaceous terrestrial strata to modern diatomaceous hemipelagic mud and volcanic ash. Bottomsimulating reflectors and the distribution of mud volcanoes, pockmarks, and acoustic wipe-out zones on the seismic records suggest the presence of subsurface gases in the sediments. The basin features stacked mass transport deposits (MTDs), but no channel-levee systems have developed. The MTDs are relatively thin (<30 m) and are derived from three sides of the basin margin. Initiation of submarine slope failure in this area may be controlled by multiple factors that increase driving forces and decrease resistance of the slopes. The driving forces include oversteepening of the margin slope as a result of thrusting and folding, and additional downslope gravitational acceleration caused by cyclic shaking during earthquakes. Decreased resistance in the slopes may be caused by the accumulation of excess pore-water pressure driven by a high-sedimentation rate, gas hydrate dissociation accompanying changes in sea level or seawater temperature, and liquefaction in coarsegrained beds during earthquakes.

Variability in coal facies as reflected by organic petrological and geochemical data in Cenozoic coal beds offshore Shimokita (Japan) - IODP Exp. 337

“…After late Miocene time the collision of the Kuril and NE Japan arcs resulted in the development of a foreland basin onshore Hokkaido (Ishikari lowland) (Noda et al, 2013).…”

Free gas accumulations in basal shear zones of mass-transport deposits (Pearl River Mouth Basin, South China Sea): An important geohazard on continental slope basins

“…Hampton et al, 1996;Masson et al, 2006;Dugan, 2012). Multiple factors such as high sedimentation rates (e.g., Dalla Valle et al, 2013;Noda et al, 2013), methane hydrate dissociation (e.g., Laberg and Vorren, 2000;Maslin et al, 2005), release of free gas (e.g., Bünz et al, 2005;Best et al, 2003;Dugan and Flemings, 2000), tectonic activity (e.g., Hance, 2003;Chadwick et al, 2012;Laberg et al, 2014), and slope oversteepening (e.g., Strozyk et al, 2010;Ikari et al, 2011) comprise important triggers for the generation of MTDs. In parallel, submarine creep zones act as a precursor of large-scale slope failure .…”

Change in slide direction of submarine landslides in the Pliocene‐Quaternary deposits near the Shimokita Peninsula, northeast Japan, using 3D seismic data

“…Volcanic activity has changed slightly in northeastern Japan since 2 Ma (Nishiki et al, 2012) initiates a large-scale landslide. The relationship between methane hydrate and landslides has been discussed for the area off Hidaka, in the northern part of the study area (Noda et al, 2013). In our study area, the presence of methane hydrate has been indicated via a bottom simulating reflector in seismic data.…”