Sample preparation, sediment core

We will present the basic requirements for preparing a bimane derivatized sample for HPLC analysis ana the preparation or appropriate blanks. We will then discuss the specific methods used for the three studies presented in the results section i) phytoplankton studies ii) sediment core studies iii) sulfide metabolism studies in invertebrate-bacteria symbiosis. 

Figure 9. Flow diagram (starting at an idealised sediment core) for the preparation of lacustrine sediment samples for the isotopic analysis of organic matter, emphasising the importance of integrating such studies with a range of other analytical techniques. Based in part on procedures u.sed by the International Decade for the East African Lakes (IDEAL) project (LRC, 1999).

The first triaxial tests on deep-sea sediment cores were performed by Moore (1964). These were run on samples from the experimental Mohole off Mexico and were mostly from sub-bottom depths greater than 75 m. Sample preparation for these compact specimens would not have been much different from conventional land procedures. 

Sediment sampling of the seven stations using the CS equipment was carried out by running transects with the survey vessel parallel to, and as close as possible to, the marker buoys. The CS underwater seafloor sediment sampler was pulled at a speed of three knots and, when abreast of each buoy, the sediment collected was recorded as being from that station. The sediment wafers prepared aboard ship from the collected slurries were immediately analyzed by XRF for three elements (Mn, Fe, and Ti) and were stored for further land-based analyses of other elements. A comparison of the elemental content of the sediments collected from the seven stations by box coring and with the use of the CS equipment constituted the basis for ground-truth evaluation of the CS system. 

Procedure for digitizing a fresh sediment surface with a digital camera 1. Prepare a flat core surface. For example, curved surfaces of cores sampled with a Livingstone or Russian corer must first be levelled off (Petterson et al., 1993, 1999). 

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