Investigations on the peach 4 debrite, a late pleistocene mass movement on the Northwest British continental margin

Abstract

The Peach 4 debrite is the most recent in a series of large scale Pleistocene MTDs within the Barra fan on the northwest British continental margin. Geophysical data indicate that Peach 4 was formed through a combination of blocky and muddy debris flows and affects an area of ∼700 km2. BGS core sample 56-10 36, located directly over the Peach 4 debrite, provides a minimum age of 14.68 ka cal BP for the last major failure. An upwards fining turbidite sequence in BGS core sample 56-10 239 is associated with increased As and S concentrations, indicators of diagenetic pyrite which forms under anoxic conditions. It is proposed that As and S concentrations may provide a method of distinguishing between contourite and turbidite sedimentation, although further research is required. © Springer Science + Business Media B.V. 2010.