| Set the Length | Labeling | Cutting |
| Setting the Length |
For geochemical processing, the sections are numbered from the surface of the mud down in 20 centimeter sections. The surface to 20 cm down is section one. 20 to 40 cm down is section two, etc. The trough will already be marked in 20 cm sections and numbered.
  When the core is laid in the trough, you will need to "set" the length. That means determining where the core actually begins -- taking into account that it may have stretched some during the extraction. There will usually be some water in the top of the core. First you need to drain the water so you can clearly see where the sediment begins. 
Next you will need to slide the liner so that the point where you determined the core sediment actually began before being stretched lines up with the first marked section of the trough.
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| Labeling the Sections |
 After laying the core liner in the trough and wiping it dry with rags, label each section of the core liner with the section number. The length of the core is determined by the number of FULL sections recovered. ** It is important to remember that the last section will be missing 3-4 inches of mud inside where the catcher was placed. Allow for this to make sure you get a full section of mud for the last section.  Three sections of the core, one each at the top, middle and bottom of the core, will be cut out and used for geochemical analysis. You will have a chart to determine which sections will be used. Clearly mark the sections to be used for geochem analysis.  |
| Cutting the Sections |
 Once the sections are marked, it's time to cut the liner. It helps to keep the liner cutter, wire for cutting the sample, some dry rags and a box of red caps next to the trough.
It takes two people to cut the liner. One person to hold the liner so it doesn't spin and another person to rotate the liner cutter. 
Once the liner is cut, a wire is used to make a clean cut through the sediment. Then each section is capped.  
Cut the sections marked for geotech processing and cap each end. Place them in a basket or crate so they don't roll around and can be carried back to the lab.
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