Microstructure maps with indicated micro-inclusions and grain boundaries (GB) of eleven samples (138-1340) m from the EastGRIP ice core

High-resolution microstructure maps were created from several hundred micro-photographs from eleven samples from the upper 1340 m of the East Greenland Ice Core Project ice core in North-East Greenland. Ice samples were drilled and processed between 2016 and 2019, microstructure mapping was performed between January 2020 and October 2020 at the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research. The samples are between 1.0 and 14.1 ka yr old and cover the Holocene, Younger Dryas, and Bolling Allerod. Sample sizes are usually 10 x 10 mm; some samples are up to 90 mm long. The maps were used to locate solid micro-inclusions 500 micrometer below the sample surface and to analyse the grain boundary area and the amount of micro-inclusions located at grain boundaries. Tiff images include the mapped micro-inclusions and can be opened with ImageJ oder Fiji. The first three or four numbers indicate the samples bag, the number after the underscore implies the section of the respective bag. Yellow dots are located micro-inclusions, colored dots are located and measured (with Raman spectroscopy) micro-inclusions. Grain boundaries are saved as .svg files and can be used with the tiff images to measure the amount of inclusions at grain boundaries. Grain boundaries and inclusions were not totally counted/analysed for EGRIP2286_3 due to a too large amount of inclusions and thus unreliable data. The methods to derive the maps are described in detail in Kipfstuhl et al. (2006) and Eichler et al. (2017).