Here we use counts of ice-rafted debris (IRD counts) mass-accumulation rates (MAR) (counts/cm²/ka), in combination with mass-accumulation rates of terrigenous leaf wax biomarkers synthesized by land plants (long chain n-alkanesMAR; mg/m²/a) from the Chilean margin which provide us information on past extent of the Patagonian ice-sheet over the past 790 000 years.For the determination of n-alkanes, 5 g of sediment samples were extracted by accelerated solvent extraction (ASE 350, Dionex) with a mixture of dichloromethane and methanol (DCM:MeOH, 9:1, v/v). The resulting total lipid extract was further separated into 3 fractions through column chromatography with silica gel as the stationary phase. n-Alkanes were eluted with Hexane (5 ml). Internal standard (squalane, C36) were added before extraction and served for quantification purposes. The n-alkanes (n-C23+25+27+29+31+33) were analysed by gas chromatography on an Agilent 7890B GC system.Mass accumulation rate (MAR) was calculated by multiplying the concentration of the compounds (ng/g sed.), by the Dry bulk density (DBD) (g/cm³), and the sedimentation rate (m/ka).