Q2. What is the effect of a liquefied layer of sediment on the sand?
A liquefied layer of sediment is known to filter out ground motions, thereby reducing the likelihood of feeling strong aftershocks.
Q3. How many km2 of seabed were surveyed?
Over 19,000 km2 of seabed were surveyed using a SEABEAM 2112 multibeam system that produced real-time bathymetry and side-scan sonar image maps.
Q4. What is the alternative for a slope failure?
For slope failure the alternatives are fluid expulsion as the source or result of rupture (or slumping in this case) (Sibson, 1981a; 1981b).
Q5. What is the reason for the change in orientation of the faults?
The change in orientation of the faults, from E-W in the east to SE-NW in the west is attributed to the diachronous westward collision.
Q6. What is the common type of erosion in the Sissano area?
The common presence of deep, mainly linear, canyons and gullies on the steeper slopes indicates active and in part localised erosion.
Q7. What are the mechanisms of failure of the sediment?
Alternative mechanisms of sediment failure range between soft sediment deformation, as in turbidites (disentegrative), to rotational slumps in cohesive sediments (non-disentegrative) (Schwab et al., 1993).
Q8. What is the sediment wedge on the inner trench slope?
On the Inner Trench Slope the sediment wedge is seaward sloping with a convex sectional profile that is deeply incised by canyons.
Q9. What is the likelihood of a major slump in the east?
In the east, the concentration and extent of fissuring, the high level of fluid expulsion features (shimmering, algal mats, chemosynthetic communites and sulphide rich sediment) together with the major sediment disturbance at the foot of the Upper Scarp support the likelihood of a major slump here.
Q10. What is the surface expression of the detachment?
The surface expressions of the detachment are the areas of exposed cohesive sediment (with rilled surfaces) observed on the steeply dipping surfaces at the top of MS Dive5 and the brecciated cliff at 1500 m on ROV Dive 1.
Q11. What is the evidence for a failure in the east?
From the evidence acquired, the authors suggest that in the amphitheatre, failure in the east was by rotational slumping with the decollement at the contact between the cohesive sediment and bedrock.
Q12. How long does the tsunami arrive at Malol?
If slump failure does indeed correspond to the 4.4 aftershock noted by the USGS, then the tsunami arrives at Malol one or two minutes after the coupled aftershocks, which agrees with eyewitness accounts.
Q13. What mechanism is the likely to explain the backtilting in the Yalingi area?
an alternative mechanism to explain the backtilting in the Yalingi area may be bynorthward directed shallow-dipping northward overthrusts.
Q14. What are the controls on fluvial sediment input to the offshore area?
Onshore controls on fluvial sediment input to the offshore area include the size of the catchment area as well as onland topography.