Supplementary Information Materials for the G-Cubed submission by Zakharov et al.

The supporting information is provided for the publication https://doi.org/10.1029/2022GC010741<em>. </em>The upload contains identification of MGL opal-CT as well as the results of the SIMS and EMPA measurements in cherts. This file also features δD values plotted against the triple O-isotope values of cherts. The Secondary Ion Probe Mass Spectrometry (SIMS) measurements are included as the .xslx table (Data Set S1) with analytical conditions, raw measurements and VSMOW-calibrated values. The Electron Microprobe (EMPA) analyses are provided in the .xslx file (Data Set S2). The Data Set S2 is separated by tabs for individual sample. Images feature the analyzed areas, including petrographic image, reflected light and the SIMS points.