The most common laboratory techniques used to investigate laminated sediments include X-radiography, core surface photography, digital, imaging, optical and scanning electron microscopy.
X-radiography. Briefly, X-radiography is based on the differential passage of X-rays through a heterogeneous media, on to X-ray-sensitive photographic film. Dense, minerogenic laminae will produce light negative images and more penetrable, biogenic laminae will produce darker negative images. Thus X-radiography provides useful information on the broad structure of the sediment column.
Digital imagery. This is a relatively new technique for producing core photographs. In digital imagery, a digitizer scans the core surface and the colour/grey scale of the sediment is recorded, producing an image similar to the standard photograph.
Optical microscopy. This technique has been used to analyse sediment fabric elements such as microfossils and lamina boundaries (i.e. whether they are gradational or sharp).
Scanning electron microscopy. The scanning electron microscope (SEM) is an ideal tool for high-resolution analysis of laminated sediments. Preparation of unconsolidated sediment using fluid-displacive resin embedding prevents fabric disturbance, and produces high-quality thin sections.
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