Endolithic weathering front induced by cyanobacteria-to-mineral interactions. Cryptoendolithic cyanobacteria which originally occupy large pores in the rock (seen in the right and upper part of the optical images as green cellular pattern) enhance their habitat by dissolution of surrounding minerals (employ locally euendolithic strategy). Increased 28Si− and 27Al16O− ion counts right at the forefront of weathering (white arrows) suggest the cyanobacteria-to-feldspar biogeochemical interfaces in the etching pits. These zones demonstrate amorphization of aluminosilicates with higher ion counts in the newly formed amorphous areas in comparison to the crystalline structures of primary minerals. Also right upper part of NanoSIMS and SEM-SE images suggest close association of clays and organic matter rich in nitrogen (area in vicinities of asterisk).