Sediment cores diluted with solvents (IMAGE) Syracuse University Caption Researchers dilute sediment cores with a variety of solvents. The samples are forced through a column of silica gel, which traps the unwanted chemicals and leaves the alkanes they want to measure. The dark line at the bottom of the liquid in the middle three columns is where some extra chemicals are getting stuck, while other chemicals can traverse through the gel to drip into vials at the bottom. Credit Syracuse University Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.