Visual stratigraphy of the EastGRIP ice core (14 m - 2021 m depth, drilling period 2017-2019)

A continuous high-resolution record of digital images in dark field illumination mode were taken from the East Greenland Ice Core Project (EastGRIP or EGRIP) ice core (Latitude: 75.630000 Longitude: -35.980000) in the depth interval from 14 m to 2121 m of depth. Stratigraphic layering in the monomineralic, and transparent polar ice is made visible in this optical setup by light scattering on second phase particles (e.g. particulate impurities such as dust, air bubbles, air clathrate hydrates) and interfaces in the polycrystal (e.g. grain boundaries, cracks and breaks). The layers are clearly visible throughout the Glacial period (> ca. 1375 m) with the most prominent and frequent ones being associated with the coldest events, also called "cloudy bands" and "clear bands". The layering firstly and mainly is depositional bedding inherited from snow accumulation and thus is assumed to be horizontal originally by representing isochrones. With increasing depth bedding can become deformed by ice flow showing mesoscale deformation structures which give insight in the local kinematic situation in 3D. This deformation can become very intense all the way up to a potential full reorganisation in deepest depths including the loss of integrity of the stratigraphic sequence, also recorded in the Visual Stratigraphy LineScan Data sets (VisStratLS).