Dating sediment cores
09-Nov-2020 10:46
If the sediment is chosen for the analysis, the reported results will be as “bulk organic carbon” or “total acid insoluble organics” depending on the sediment fractions included in the analysis.For sediment samples, the lab performs flotation in water then progressive sieving through 225-micron, 180-micron, and then 125-micron sieves to see if there are any macrofossils that can be extracted.
Every year, billions of tons of dead plankton and other marine organisms, dust blown from far-off lands, and river sediment settle on the ocean floor on top of materials from previous years.The sharp boundary between light- and dark-brown sediments in this core is also visible in similarly aged cores from around the world.About 55 million years ago, an enormous amount of CO was absorbed by the ocean, quickly changing its composition.Examples of these macrofossils include charcoal, wood, plant, bone, shell, and seeds.
Note: Our lab does not identify the exact type of macrofossil found in the sediment.Access to society journal content varies across our titles.