what part of the ice core is actually examined by scientists
Ice core Impurities in the ice provide information on the environment from when they were deposited. These include soot, ash, and other types of particle from forest fires and volcanoes; isotopes such as beryllium-10 created by cosmic rays; micrometeorites; and pollen.[1] The lowest layer of a glacier, called basal ice, is frequently formed of subglacial meltwater that has refrozen. It can be up to about 20 m thick, and though it has scientific value (for example, it may contain subglacial microbial populations),[7] it often does not retain stratigraphic information.[8]