The data set consists of rock samples collected from Coquetdale, Coldstream and Whitrope Burn from 2013-2014; milled material is included. There is an Excel spreadsheet of sample numbers with location, sample height on log, d13C data and %C. There are scans of field logs from Coquetdale, Coldstream and Whitrope Burn, and Illustrator drawn logs from Coldstream which include samples collected at a later date. Scans of thin sections are also included. (thin sections to be kept at Leicester for the time being – still being worked on for papers.) Each locality folder has an Excel spreadsheet detailing samples, sample height, %C and bulk and specific d13C values. These data were used to interpret the environment in which early tetrapods have been found in the early Carboniferous. These data supported the MPhil thesis 'In an alternating marine and non-marine depositional setting, where and how are early Carboniferous tetrapods preserved?' by Sherwin, 2018, and one publication including data from Whitrope Burn - Richards et al., 2018, (https://doi.org/10.1017/S1755691018000166).