Sediment Microfabric of Oil Rig Drill Spoil Heaps: Preliminary Observations Using Low-Temperature Scanning Electron Microscopy

Abstract

Low-temperature scanning electron microscopy is a specialized technique shown to be appropriate for the high-resolution examination of unconsolidated sea floor sediments. Newly developed cryogenic sediment sampling techniques combined with low-temperature scanning electron microscopy (LTSEM) protocols developed for the analysis of biological materials now permits the sampling of fully hydrated bottom sediments while preserving the structural integrity of the sampled material. This enables the direct observation of the sediment fabric as it exists at the seabed and the examination of delicate biological structures that are normally obliterated or distorted by the removal of water required for standard SEM preparation. This paper demonstrates the value of LTSEM and shows variation in microfabric structure between a station located on a spoil heap below an oil rig and a more remote (400 m distant) station. Energy-dispersive X-ray analysis (EDXA) was also conducted on the frozen samples and provided support f...