Data underlying the figures and supplementary data files associated with the accepted manuscript "Microbial methane production from calcium carbonate at moderately alkaline pH". README files are included for the figures file (version 2) and for supplementary data 1. The supplementary data 2 file is a log of commands used in the bioinformatic analyses. Description for version 1 files: Data underlying eight figures found in the manuscript "Methanogenesis from calcium carbonate at moderately alkaline pH by a microbial community enriched from saline wetland soil". A ReadMe file is included.