Sediment disturbance and correlation of offset holes drilled with the Hydraulic Piston Corer: Leg 94.

Abstract

At Sites 607 through 611, drilling on Leg 94 with the Hydraulic Piston Corer retrieved cores in upper sediment layers with large-scale CaCO3 variations related to Pleistocene and late Pliocene glaciations over the last 2.5Ma. The visually striking color-layering caused by these variations permitted detailed correlations between holes on a scale not possible with shipboard paleomagnetics and biostratigraphy. These correlations indicate that demonstrably continuous sections extending back to at least 2Ma were retrieved at Sites 607 to 610. There appears to be a gap in record continuity at Site 611 in the upper Pleistocene. Making these correlations on site during Leg 94 enabled us to recore intervals where loss of continuity was known or suspected.-Authors